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This month on the Node and beyond

Posted by , on 7 February 2017

January was a productive month on the Node, with a variety of developmental biology content from the lab bench and beyond.

 

Research

We heard from the authors of a bunch of recent papers, including Ripla Arora on her recent Development paper on imaging the implanting embryo and uterine environment in 3D, and Kyle Martin on his recent PNAS paper which links taste, teeth and scales in sharks.

 

 

Nitya Ramkumar told us what Crumbs has to do with cell shape and gastrulation, highlighting her recent NCB paper, and Sylvia Dyballa and Cristina Pujades intorduced their eLife paper on using 4D imaging to understand inner ear morphogenesis. Highlighting another eLife paper, Ko Currie told us how planarian adults controlled neurogenesis.

 

People

Our People behind the Papers series continued with Miguel Brun-Usan and Isaac Salazar-Ciudad (University of Helsinki) on modelling and embryology, and Ehsan Pourkarimi and Iestyn Whitehouse (Sloan-Kettering, NY) on DNA replication and gene transcription.

 

 

Isabel Almudi, a postdoc in Fernando Casares’ lab in Seville, walked us through a day in the life of a mayfly lab and the beautiful eyes of the male flies.

 

 

We heard from three Company of Biologists Travelling Fellows – Hanna Hakkinen,  Nanami Morooka and Tetsuto Miyashita – who collectively crossed continents to learn new techniques in host labs.

 

 

Testsuto also told us about a meeting he had been to: the First International Hemichordate Meeting, and celebrated the potential of this enigmatic group of animals. We also heard from four undergraduate students who had received the Gurdon/The Company of Biologists Summer Studentships from the BSDB.

 

Beyond the lab

Valerie Butler argued for culturally relevant science education, to increase engagement and representation. Finally, a couple of resources: first in our latest round up of developmental biology preprints, and second in the awesome Lifemap, a zoomable and addictive online tool for exploring the tree of life, as introduced by its creator Damien de Vienne.

 

Around the web

 

The best tweets

 

 

https://twitter.com/AuditoryNerves/status/824301219460030464

 

 

 

https://twitter.com/FredrikJutfelt/status/823512955522256896

 

 

 

 

 

 

 

 

 

 

 

https://twitter.com/vividbiology/status/818491340489162752

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

https://twitter.com/debivort/status/823934351985545216

 

 

 

 

 

 

 

 

 

 

 

 

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PhD Scholarship – The Role of Cell Polarity in Tissue Repair

Posted by , on 7 February 2017

Closing Date: 15 March 2021

(A/Prof Helena Richardson’s & Prof Patrick Humbert’s laboratories at the Department of Biochemistry & Genetics, La Trobe Institute of Molecular Sciences (LIMS), La Trobe University Melbourne Campus (Bundoora)

 

We offer a PhD scholarship to an exceptional student (who has achieved a H1 Honours or equivalent) to determine how cell polarity perturbations affect signalling pathways in tissue repair. The project utilizes the model organism, Drosophila, and mammalian epithelial cell culture. This project will have important implications for understanding wound healing as well as cancer.

 

The Applicant should have Australian citizenship or residency. They should be highly driven and have a high level of achievement, including a first class Honours degree or equivalent in the field of Cell Biology and/or Genetics. Knowledge of Cell Biology theory and techniques is essential, and knowledge of Genetics, Molecular Biology and Biochemistry approaches is desirable. Experience in the Drosophila model organism, although not essential, will be highly beneficial.

 

The project will address the role of cell shape (polarity) regulation in epithelial tissue homeostasis, using an in vivo approach utilizing the Drosophila model system, and an in vitro approach with cultured mammalian epithelial cells. Sophisticated genetic techniques will be used to generate mutant patches of cells within an epithelium and the effect on cell morphology, cell extrusion, signalling pathways, cell proliferation, apoptosis and protein-protein interactions will be monitored utilizing sophisticated cell biological approaches involving fixed samples or live cell imaging. The project seeks to reveal novel mechanisms by which mutant cells interact with their microenvironment that can be utilized therapeutically to improve wound repair or to enhance elimination of the mutant cells.

 

Benefits of the scholarship

Benefits of the scholarship include:

  • A La Trobe University Research Scholarship for three years, with a value of $26,288 per annum, to support your living costs [2016 rate]
  • Opportunities to work with outstanding researchers at the Department of Biochemistry & Genetics, LIMS and have access to cutting-edge equipment and professional development programs
  • Opportunities for authorship on high impact scientific manuscripts.
  • Opportunities to attend national and international conferences

 

How to apply

  • Review how to apply for a graduate research scholarship at: http://www.latrobe.edu.au/research/future/apply
  • Contact A/Prof. Helena Richardson by email at h.richardson@latrobe.edu.au, with a full CV, academic transcript, and a cover letter outlining why you would like to be considered for this scholarship.
  • A/Prof Helena Richardson and Prof Patrick Humbert at the Department of Biochemistry & Genetics, LIMS will carefully review your application and consider you for this Scholarship.
  • The successful applicant who receives in-principle agreement for supervision, will then submit a complete PhD application to the La Trobe Graduate Research School, attaching a copy of the agreement to admissions.grs@latrobe.edu.au

 

You will be advised of an outcome by 30th April, 2017.

 

Closing date

Applications close 1 April 2017, unless filled sooner.

 

Contact us

If you require further information, please contact:  h.richardson@latrobe.edu.au or the La Trobe University Graduate Research School: grs@latrobe.edu.au

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PhD Scholarship – Embryo Development and Craniofacial Defects Research

Posted by , on 7 February 2017

Closing Date: 15 March 2021

A Ph.D. scholarship offered to an exceptional student, to investigate genetic mechanisms which underpin vertebrate birth defects, with a particular focus on craniofacial defects such as cleft palate.

 

This scholarship will be offered to an independent, proactive, forward thinking and enthusiastic candidate, who wishes to forge an independent career in science.

 

Applicants should have a high level of achievement, including a first class honours degree or equivalent.

 

As an applicant you should have an interest in developmental genetics and understanding the processes which govern embryo formation, as well as a keen interest and aptitude in biochemistry and molecular genetics. Your project will address biological and cellular behaviours which regulate how the vertebrate embryos forms, using the mouse, and zebrafish as genetic developmental models.


Benefits of the scholarship

Benefits of the scholarship include:

  • a La Trobe Research Scholarship for three years, with a value of $26,288 per annum, to support your living costs [2016 rate]
  • a fee-relief scholarship (LTUFFRS) for four years to undertake a PhD at La Trobe University (international applicants only)
  • opportunities for authorship on high impact scientific manuscripts.
  • opportunities to attend national and international conferences
  • opportunities to work with La Trobe’s outstanding researchers, and have access to our suite of professional development programs


How to apply

  • Review how to apply for a graduate research scholarship at: http://www.latrobe.edu.au/research/future/apply
  • Contact Dr. Seb Dworkin by email at s.dworkin@latrobe.edu.au, with a full CV, academic transcript, and a cover letter outlining why you would like to be considered for this scholarship.
  • Dr. Dworkin, and the Department of Physiology, Anatomy and Microbiology will carefully review your application and consider you for this Scholarship.
  • The successful applicant who receives in-principle agreement for supervision, will then submit a complete PhD application to the La Trobe Graduate Research School, attaching a copy of the agreement to admissions.grs@latrobe.edu.au

 

You will be advised of an outcome by 30th April, 2017.

 

Closing date

Applications close 1 April 2017, unless filled sooner.

 

Contact us

If you require further information, please contact:  s.dworkin@latrobe.edu.au or the La Trobe University Graduate Research School: grs@latrobe.edu.au

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Postdoctoral Position Developmental and Cancer Biology

Posted by , on 6 February 2017

Closing Date: 15 March 2021

An NIH-funded postdoctoral researcher position is available immediately in Dr. Nadia Dahmane laboratory at Cornell University-Weill Cornell Medicine in the Department of Neurological Surgery to study the transcriptional regulation of normal brain development and brain tumor progression. Our group uses cell biology, mouse genetics, biochemical and genomic approaches to decipher the cellular and molecular mechanisms controlling brain development and brain tumor progression (e.g. Xiang et al. Cell Death and Differentiation 2012; Baubet et al., Development 2012,Tatard et al., Cancer Research 2010; Deng et al. Journal of Cell Science 2012).

We seek enthusiastic, highly qualified and motivated individuals to join our research group. The successful candidate should have a Ph.D. degree with a strong background in molecular biology, cell biology, and/or biochemistry. Research experience in developmental neuroscience, cancer biology and animal models of brain diseases would be considered advantageous.

Our laboratory is located on the Weill Cornell Medicine campus in New York City.

Please submit your CV and a cover letter outlining your research interests, career goals and the names of three referees with contact information to Dr. Nadia Dahmane at: nad2639@med.cornell.edu

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From our sister journals – December & January

Posted by , on 6 February 2017

Here we highlight some developmental biology related content from other journals published by The Company of Biologists.

Journal typography

JCS kicked off 2017 with a Special Issue relevant to many developmental biologists: 3D cell biology. It’s packed full of commentaries, interviews, research articles and techniques, and well worth a browse.

 

Brian Stramer of King’s College, London, a big fan of contact inhibition of locomotion, was featured as a cell scientist to watch.

 

Nicole Gorfinkiel and colleagues showed that α- Catenin stabilises actomyosin foci and E-Cadherin to promote apical contraction in the Drosophila amnioserosa.

 

Masahiko Takemura and Hiroshi Nakato implicate a heparan sulfate endosulfatase in stem cell divisions during homeostasis and regeneration.

 

John Wallingford and colleagues explore the role of RhoA and actin in the emergence of a new apical surface in Xenopus  multiciliated cells.

 

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Mi Hye Song and colleagues report a role for Casein kinase II  in the early cell divisions of the C. elegans embryo

 

Shaun Collin and colleagues track the development and distribution of taste papillae and oral denticles in the bamboo shark.

 

Ottoline Leyser and colleagues investigate how the plant hormone strigolactone regulates shoot development.

 

Kelly Smith and colleagues describe how single nucleotide polymorphisms can increase the efficiency of CRISPR/CAS9 genome editing in zebrafish.

 

CoB_DisModMech_AW_RGB

Vivian Siegel payed tribute to her lifelong mentor Susan Lindquist

 

Douglas Epstein and colleagues link prenatal ethonal exposure and Shh pathway mutants with optic nerve hypoplasia.

 

Journal typography

In their review, Todd Gillis and colleagues explore temperature-induced cardiac remodelling in fish.

Mark Denny explores the fallacy of the average: why biologists should take account of Jensen’s inequality.

Daniel Rittschof and colleagues explore the metamorphosis of barnacles, and their relationship to bacteria.

Belinda Chang and colleagues identify a second visual rhodopsin in zebrafish and categorise its properties and evolutionary history.

 

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Research Technician position near Washington DC

Posted by , on 3 February 2017

Closing Date: 15 March 2021

A position (#122764) is available immediately for a Research Technician/Faculty Specialist to contribute to our studies in neural crest and placodes. The Technician will conduct research, assist in the training of students, and take part in the management of the laboratory of Dr. Lisa Taneyhill at the University of Maryland. Laboratory skills should include the ability to perform various molecular biology and biochemical assays, such as recombinant DNA/cloning; immunoprecipitation and immunoblotting; and/or immunohistochemistry. Experience with microscopy, chick embryology, and tissue culture is desirable. For more information on the lab, please see http://www.ansc.umd.edu/people/lisa-taneyhill. A Bachelor’s degree (B.A. or B.S.) in a related field and prior laboratory research experience is essential. Fluency in spoken and written English is required. Salaries are highly competitive, negotiable and commensurate with qualifications. Fringe benefits offered. Applicants must apply through eTerp at https://ejobs.umd.edu. Applications will be accepted until a suitable candidate is identified.

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January in preprints

Posted by , on 3 February 2017

Our latest monthly trawl for developmental biology (and other cool) preprints. See June’s introductory post for background, and let us know if we missed anything

 

2017 started where 2016 had left off, with an number of preprints covering most corners of developmental biology, plus more relevant work from related fields. Looking at the list below, it’s clear that a mix of young and established labs are using preprints. Following the trends of last year, they were predominantly found on bioRxiv, with some also on arXiv and PeerJ Preprints.

This month features regeneration in mouse digits and whole ascidians, how body axes form in gastruloids, the link between metabolism and signalling in mice, and developmental plasticity in Arabidopsis. There also were a whole bunch of fly papers, and new tools including a new ImageJ and ‘WikiGenomes’. Happy preprinting!

 

Cytoplasmic flows in the Drosophila oocyte from Drechsler, et al.

 

Developmental biology

 | Genes & chromosomes

Abortive Initiation as a Bottleneck for Transcription in the Early Drosophila Embryo. Alexander S. Serov, Alexander J. Levine, Madhav Mani

 

The Drosophila Dosage Compensation Complex activates target genes by chromosome looping within the active compartment. Tamas Schauer, Yad Ghavi-Helm, Tom Sexton, Christian Albig, Catherine Regnard, Giacomo Cavalli, Eileen E M Furlong, Peter B Becker

 

Genome-wide Search for Zelda-like Chromatin Signatures Identifies GAF as a Pioneer Factor in Early Fly Development. Arbel Moshe, Tommy Kaplan

 

Polycomb-Mediated Chromatin Loops Revealed by a Sub-Kilobase Resolution Chromatin Interaction Map. Kyle P. Eagen, Erez Lieberman Aiden, Roger D. Kornberg

 

The Nucleosome Remodelling and Deacetylation complex restricts Mediator access to enhancers to control transcription. Maria Xenophontos, Nicola Reynolds, Sarah Gharbi, Ewan Johnstone, Jason Signolet, Robin Floyd, Meryem Ralser, Susanne Borneloev, Sabine Dietmann, Remco Loos, Paul Bertone, Brian Hendrich

 

Targeted degradation of CTCF decouples local insulation of chromosome domains from higher-order genomic compartmentalization. Elphege P Nora, Anton Goloborodko, Anne-Laure Valton, Johan Harmen Gibcus, Alec Uebersohn, Nezar Abdennur, Job Dekker, Leonid Mirny, Benoit Bruneau

 

Lateral elements and transverse filaments of the synaptonemal complex, from Chrichton, et al.

 

Defects in Meiotic Recombination Delay Progression Through Pachytene in Mouse Spermatocytes. James H Crichton, David R Read, Ian R Adams

 

Tex19.1 Regulates Meiotic DNA Double Strand Break Frequency in Mouse Spermatocytes. James H Crichton, Christopher J Playfoot, Marie MacLennan, David Read, Howard J Cooke, Ian R Adams

 

Spacer sequences separating transcription factor binding motifs set enhancer quality and strength. Marion Gueroult-Bellone, Kazuhiro R Nitta, Willi Kari, Edwin Jacox, Remy Beule Dauzat, Renaud Vincentelli, Carine Diarra, Ute Rothbacher, Christelle Dantec, Christian CAMBILLAU, Jacques Piette, Patrick Lemaire

 

Direct visualization of transcriptional activation by physical enhancer-promoter proximity. Hongtao Chen, Miki Fujioka, James B Jaynes, Thomas Gregor

 

Diverse yet highly selective interorgan crosstalk mechanisms shape the bodywide transcriptome landscape. Norio Takada, Madoka Omae, Fumihiko Sagawa, Neil Chi, Satsuki Endo, Satoshi Kozawa, Thomas N Sato

 

| Patterning & signalling

A defined platform of human peri-gastrulation-like biological fate patterning reveals coordination between Reaction-Diffusion and Positional-Information. Mukul Tewary, Joel E Ostblom, Nika Shakiba, Peter W Zandstra

 

Expression of the GATA6::H2B-Venus reporter in the gastruloids of Turner, et al.

 

Gastruloids develop the three body axes in the absence of extraembryonic tissues and spatially localised signalling. David Turner, Luz Alonso-Crisostomo, Mehmet Girgin, Peter Baillie-Johnson, Cherise R Glodowski, Penelope C Hayward, Jérôme Collignon, Carsten Gustavsen, Palle Serup, Benjamin Steventon, Matthias Lutolf, Alfonso Martinez Arias

 

Early frameshift alleles of zebrafish tbx5a that fail to develop the heartstrings phenotype. Elena Chiavacci, Lucia Kirchgeorg, Anastasia Felker, Alexa Burger, Christian Mosimann

 

Multiple zebrafish atoh1 genes specify a diversity of neuronal types in the zebrafish cerebellum. Chelsea U. Kidwell, Chen-Ying Su, Masahiko Hibi, Cecilia B. Moens

 

Olig2 and Hes regulatory dynamics during motor neuron differentiation revealed by single cell transcriptomics. Andreas Sagner, Zachary Gaber, Julien Delile, Jennifer H Kong, David L Rousso, Caroline A Pearson, Steven E Weicksel, Neda Mousavy Gharavy, James Briscoe, Bennett Novitch

 

Warburg-like metabolism coordinates FGF and Wnt signaling in the vertebrate embryo. Masayuki Oginuma, Philippe Moncuquet, Fengzhu Xiong, Edward Karoly, Jerome Chal, Karine Guevorkian, Olivier Pourquie

 

Semaphorin-Plexin signaling influences early ventral telencephalic development and thalamocortical axon guidance. Manuela D. Mitsogiannis, Graham E. Little, Kevin J Mitchell

 

A damped oscillator imposes temporal order on posterior gap gene expression in Drosophila. Berta Verd, Erik Clark, Karl R. Wotton, Hilde Janssens, Eva Jimenez-Guri, Anton Crombach, Johannes Jaeger

 

Dynamic Maternal Gradients Control Timing and Shift-Rates for Gap Gene Expression. Berta Verd, Anton Crombach, Johannes Jaeger

 

Functional regulatory evolution outside of the minimal even-skipped stripe 2 enhancer. Justin Crocker, David L. Stern

 

Double fluorescent in situs in Drosophila embryos from Erik Clark’s preprint.

 

Dynamic patterning by the Drosophila pair-rule network reconciles long-germ and short-germ segmentation. Erik Clark

 

The scaffolding protein Cnk Interacts with Alk to Promote Visceral Founder Cell Specification in Drosophila. Georg Wolfstetter, Kathrin Pfeifer, Jesper R. vanDijk, Fredrik Hugosson, Xiangyi Lu, Ruth H. Palmer

 

PEAPOD limits developmental plasticity in Arabidopsis. Derek W. R. White

 

| Morphogenesis & Mechanics

Quantification of myosin distribution predicts global morphogenetic flow in the fly embryo. Sebastian J Streichan, Matthew F Lefebvre, Nicholas Noll, Eric F Wieschaus, Boris I Shraiman

 

Active diffusion and advection in the Drosophila ooplasm result from the interplay of the actin and microtubule cytoskeletons. Maik Drechsler, Fabio Giavazzi, Roberto Cerbino, Isabel M Palacios

 

Myosin II activity is not required for Drosophila tracheal branching morphogenesis. Amanda Ochoa-Espinosa, Stefan Harmansa, Emmanuel Caussinus, Markus Affolter

 

Astral microtubule dynamics regulate anaphase oscillation onset and set a robust final position of the C. elegans zygote spindle. Helene Bouvrais, Laurent Chesneau, Sylvain Pastezeur, Marie Delattre, Jacques Pecreaux

 

Cortical elasticity determines the geometry of prospective mesoderm constriction in Drosophila melanogaster. Konstantin Doubrovinski

 

| Stem cells, regeneration & ageing

Molecular and functional variation in iPSC-derived sensory neurons. Jeremy Schwartzentruber, Stefanie Foskolou, Helena Kilpinen, Julia Rodrigues, Kaur Alasoo, Andrew J Knights, Minal Patel, Angela Goncalves, Rita Ferreira, Caroline L Benn, Anna Wilbrey, Magda Bictash, Emma Impey, Lishuang Cao, Sergio Lainez, Alexandre J Loucif, Paul J Whiting, HIPSCI Consortium, Alex Gutteridge,Daniel J Gaffney

 

Schematic of experimental design from Stumpf, et al’s study.

 

Stem cell differentiation is a stochastic process with memory. Patrick S. Stumpf, Rosanna C. G. Smith, Michael Lenz, Andreas Schuppert, Franz-Josef Müller, Ann Babtie, Thalia E. Chan, Michael P. H. Stumpf, Colin P. Please, Sam D. Howison, Fumio Arai, Ben D. MacArthur

 

Production of Multilayer Cell Mass from Olfactory Stem Cell and Its Utilization Potential in Nervous Tissue Regeneration. Olga Nehir Nehir Oztel, Adil M. Allahverdiyev, Aysegul Batioglu Karaaltin, Melahat Bagirova, Ercument Ovali

 

Non-viral induction of transient cell reprogramming in skeletal muscle to enhance tissue regeneration. Irene de Lazaro, Acelya Yilmazer, Yein Nam, Sarah Qubisi, Fazilah Maizatul Abdul Razak, Giulio Cossu, Kostas Kostarelos

 

Targeted gene correction of FKRP by CRISPR/Cas9 restores functional glycosylation of α-dystroglycan in cortical neurons derived from human induced pluripotent stem cells. Beatrice Lana, Jihee Kim, David Ryan, Evangelos Konstantinidis, Sandra Louzada, Beiyuan Fu, Fengtang Yang, Derek L. Stemple, Pentao Liu, Francesco Muntoni, Yung-Yao Lin

 

Integrated time-lapse and single-cell transcription studies highlight the variable and dynamic nature of human hematopoietic cell fate commitment. Alice Moussy, Jeremie Cosette, Romuald Parmentier, Cindy da Silva, Guillaume Corre, Angelique Richard, Olivier Gandrillon, Daniel Stockholm, Andras Paldi

 

FGFR1 expression in the perinatalmouse brain, from Collette, et al.

 

Glial and stem cell expression of Fibroblast Growth Factor Receptor 1 in the embryonic and perinatal nervous system. Jantzen C Collette​, Lisha Choubey​, Karen Muller Smith.

 

Transcriptome analysis of genetically matched human induced pluripotent stem cells disomic or trisomic for chromosome 21. Patrick K. Gonzales, Virginia Fonte, Christine M. Roberts, Connor Jacobsen, Gretchen H Stein, Christopher D. Link

 

Yorkie is required to restrict the injury responses in planarians. Alexander Y.T. Lin, Bret J Pearson

 

Macrophages are required to coordinate mouse digit tip regeneration. Ken Muneoka, Jennifer Simkin, Mimi Sammarco, Luis Marrero, Lindsay Dawson, Mingquan Yan, Catherine Tucker, Alex Cammack

 

Histological and haematological analysis of the ascidian Botrylloides leachii (Savigny, 1816) during whole-body regeneration. Simon Blanchoud, Lisa Zondag, Miles K Lamare, Megan J Wilson

 

Multi-generational silencing dynamics control cell aging. Yang Li, Meng Jin, Richard O’Laughlin, Lev S Tsimring, Lorraine Pillus, Jeff Hasty, Nan Hao

 

Age-dependence and aging-dependence: The case of neuronal loss and lifespan in a C. elegans model of Parkinson’s disease. Javier Apfeld, Walter Fontana

 

The differential spatiotemporal expression pattern of shelterin genes throughout lifespan. Kay-Dietrich Wanger, Yilin Ying, Waiian Leong, Jie Jiang, Xuefei Hu, Yi Chen, Jean-Francois Michiels, Yiming Lu, Eric Gilson, Nicole Wagner, Jing Ye

 

 

Cell biology

Mapping load-bearing in the mammalian spindle reveals local kinetochore-fiber anchorage that provides mechanical isolation and redundancy. Mary Williard Elting, Manu Prakash, Dylan B. Udy, Sophie Dumont

 

Phenotypic classes from Dudin, et al.’s screen.

 

A systematic screen for morphological abnormalities during fission yeast sexual reproduction identifies a mechanism of actin aster formation for cell fusion. Omaya Dudin, Laura Merlini, Felipe O Bendezu, Raphael Groux, Vincent Vincenzetti, Sophie G Martin

 

Photorelease of Diacylglycerol Increases the Amplitude and Duration of Protein Kinase C-BetaII Relocation in cyto. Joachim Goedhart, Theodorus W.J. Gadella

 

Crawling chytrid fungi implicate actin regulators WASP and SCAR in an ancient mode of cell motility. Lillian K. Fritz-Laylin, Samuel J. Lord, R. Dyche Mullins

 

Distinguishing Mechanisms Underlying EMT Tristability. Dongya Jia, Mohit Kumar Jolly, Satyendra Chandra Tripathi, Petra Den Hollander, Bin Huang, Mingyang Lu, Muge Celiktas, Esmeralda Ramirez-Pena, Eshel Ben-Jacob, Jose N. Onuchic, Samir M. Hanash, Sendurai A. Mani, Herbert Levine

 

Asymmetric adhesion of rod-shaped bacteria controls microcolony morphogenesis. Marie-Cecilia Duvernoy, Thierry Mora, Maxime Ardre, Vincent Croquette, David Bensimon, Catherine Quilliet, Jean-Marc Ghigo, Martial Balland, Christophe Beloin, Sigolene Lecuyer, Nicolas Desprat

 

A checkpoint roadmap for the complex cell division of Apicomplexa parasites. Carmelo A Alvarez, Elena S Suvorova

 

Evo-devo & evo

A miRNA catalogue and ncRNA annotation of the short-living fish Nothobranchius furzeri. Mario Baumgart, Emanuel Barth, Aurora Savino, Marco Groth, Philipp Koch, Andreas Petzold, Ivan Arisi, Matthias Platzer, Manja Marz, Alessandro Cellerino

 

The minute wing phenotype in silkworms, from Yu, et al.

 

Mutation of a palmitoyltransferase ZDHHC18-like gene is responsible for the minute wing mutation in the silkworm (Bombyx mori). Ye Yu, Xiaojing Liu, Xiao Ma, Zhongjie Zhang, Na Liu, Chengxiang Hou, Muwang Li

 

The RAG transposon is active through the deuterostome evolution and domesticated in jawed vertebrates. Jose Ricardo Poole, Sheng Feng Huang, An Long Xu, Pontarotti Pierre

 

It′s okay to be green: Draft genome of the North American Bullfrog (Rana [Lithobates] catesbeiana). S Austin Hammond, René L Warren, Benjamin P Vandervalk, Erdi Kucuk, Hamza Khan, Ewan A Gibb, Pawan Pandoh, Heather Kirk, Yongjun Zhao, Martin Jones, Andrew J Mungall, Robin Coope, Stephen Pleasance, Richard A Moore, Robert A Holt, Jessica M Round, Sara Ohora, Nik Veldhoen, Caren C Helbing, Inanc Birol

 

Revisiting suppression of interspecies hybrid male lethality in Caenorhabditis nematodes. Lauren E Ryan, Eric S Haag

 

Large-scale rewiring in a yeast hybrid. Rebecca Herbst, Dana Bar-Zvi, Sharon Reikhav, Ilya Soifer, Michal Breker, Ghil Jona, Eyal Shimoni, Maya Schuldiner, Avraham Levy, Naama Barkai

 

No evidence for the radiation time lag model after whole genome duplications in Teleostei. Sacha Laurent, Nicolas Salamin, Marc Robinson-Rechavi

 

Hybrid incompatibility caused by an epiallele. Todd Blevins, Jing Wang, David Pflieger, Frédéric Pontvianne, Craig S. Pikaard

 

Evaluation and rational design of guide RNAs for efficient CRISPR/Cas9-mediated mutagenesis in Ciona. Shashank Gandhi, Maximilian Haeussler, Florian Razy-Krajka, Lionel Christiaen, Alberto Stolfi

 

Tools & Resources

Escape Excel: a tool for preventing gene symbol and accession conversion errors. Eric A Welsh, Paul A Stewart, Brent M Kuenzi

 

ImageJ2: ImageJ for the next generation of scientific image data. Curtis T. Rueden, Johannes Schindelin, Mark C. Hiner, Barry E. DeZonia, Alison E. Walter, Kevin W. Eliceiri

 

WikiGenomes: an open Web application for community consumption and curation of gene annotation data in Wikidata. Tim E Putman, Sebastien Lelong, Sebastian Burgstaller-Muelhbacher, Andra Waagmeester, Colin Diesh, Nathan Dunn, Monica Munoz-Torres, Gregory Stupp, Andrew Su, Benjamin M Good

 

Measuring physiological responses to stressors using a novel Hmox1 reporter mouse. Michael McMahon, Shaohong Ding, Lourdes P Acosta-Jimenez, Tania G Frangova, Colin J Henderson, C. Roland Wolf

 

A toolkit for tissue-specific protein degradation in C. elegans. Shaohe Wang, Ngang Heok Tang, Pablo Lara-Gonzalez, Bram Prevo, Dhanya K Cheerambathur, Andrew D Chisholm, Arshad Desai, Karen Oegema

 

Whole genome sequencing and assembly of a Caenorhabditis elegans genome with complex genomic rearrangements using the MinION sequencing device. John R Tyson, Nigel J O’Neil, Miten Jain, Hugh E Olsen, Philip Hieter, Terrance P Snutch

 

Progress Towards a Public Chemogenomic Set for Protein Kinases and a Call for Contributions. David H Drewry, Carrow I Wells, David M Andrews, Richard Angell, Hassan Al-Ali, Alison D Axtman, Stephen J Capuzzi, Jonathan M Elkins, Peter Ettmayer, Mathias Frederiksen, Opher Gileadi, Nathanael Gray, Alice Hooper, Stefan Knapp, Stefan Laufer, Ulrich Luecking, Susanne Muller, Eugene Muratov, R. Aldrin Denny, Kumar S Saikatendu, Daniel K Treiber, William J Zuercher, Timothy M Willson

 

The 4D Nucleome Project, from Dekker, et al.

 

The 4D Nucleome Project. Job Dekker, Andrew S Belmont, Mitchell Guttman, Victor O Leshyk, John T Lis, Stavros Lomvardas, Leonid A Mirny, Clodagh C O’Shea, Peter J Park, Bing Ren, Joan C Ritland, Jay Shendure, Sheng Zhong, The 4D Nucleome Network

 

Mass-spectrometry of single mammalian cells quantifies proteome heterogeneity during cell differentiation. Bogdan Budnik, Ezra Levy, Nikolai Slavov

 

Interactive analysis of Long-read RNA isoforms with Iso-Seq Browser. Jingyuan Hu, Prech Uapinyoying, Jeremy Goecks

 

Genome Graphs. Adam M Novak, Glenn Hickey, Erik Garrison, Sean Blum, Abram Connelly, Alexander Dilthey, Jordan Eizenga, M. A. Saleh Elmohamed, Sally Guthrie, André Kahles, Stephen Keenan, Jerome Kelleher, Deniz Kural, Heng Li, Michael F Lin, Karen Miga, Nancy Ouyang, Goran Rakocevic, Maciek Smuga-Otto, Alexander Wait Zaranek, Richard Durbin, Gil McVean, David Haussler, Benedict Paten

 

Multiplexed dynamic imaging of genomic loci in single cells by combined CRISPR imaging and DNA sequential FISH. Yodai Takei, Sheel Shah, Sho Harvey, Lei S Qi, Long Cai

 

CRISPR-RT: A web service for designing CRISPR-C2c2 crRNA with improved target specificity. Houxiang Zhu, Emily Richmond, Chun Liang

 

The 3D genome organization of Drosophila melanogaster through data integration. Qingjiao Li, Harianto Tjong, Xiao Li, Ke Gong, Xianghong Jasmine Zhou, Irene Chiolo, Frank Alber

 

Bayesian inference of agent-based models: a tool for studying kidney branching morphogenesis. Ben Lambert, Adam L MacLean, Alexander G Fletcher, Alexander N Coombes, Melissa H Little, Helen M Byrne

 

Cell fixation and preservation for droplet-based single-cell transcriptomics. Jonathan Alles, Samantha Praktiknjo, Nikos Karaiskos, Stefanie Grosswendt, Salah Ayoub, Luisa Schreyer, Anastasiya Boltengagen, Christine Kocks, Nikolaus Rajewsky

 

Pebbles as Dry Ice Replacement for Snap Freezing of Rodents Brains. Rene Bernard, Larissa Mosch, Ulrich Dirnagl

 

Accurate alignment between correlated light, cryo-light, and electron cryo-microscopy data using sample support features. Karen L Anderson, Christopher Page, Mark F Swift, Dorit Hanein, Niels Volkmann

 

 

Research practice

Data Reuse as a Prisoner’s Dilemma: the social capital of open science. Bradly Alicea

 

Biocuration as an undergraduate training experience: Improving the annotation of the insect vector of Citrus greening disease. Surya Saha, Prashant S Hosmani, Krystal Villalobos-Ayala, Sherry Miller, Teresa Shippy, Andrew Rosendale, Chris Cordola, Tracey Bell, Hannah Mann, Gabe DeAvila, Daniel DeAvila, Zachary Moore, Kyle Buller, Kathryn Ciolkevich, Samantha Nandyal, Robert Mahoney, Joshua Von Voorhis, Megan Dunlevy, David Farrow, David Hunter, Taylar Morgan, Kayla Shore, Victoria Guzman, Allison Izsak, Danielle E Dixon, Liliana Cano, Andrew Cridge, Shannon Johnson, Brandi L Cantarel, Stephen Richardson, Adam English, Nan Leng, Xiaolong Cao, Haobo Jiang, Chris Childers, Mei-Ju Chen, Mirella Flores, Wayne Hunter, Michelle Cilia, Lukas A Mueller, Monica Munoz-Torres, David Nelson, Monica F Poelchau, Josh Benoit, Helen Wiersma-Koch, Tom D’elia, Susan J Brown

 

Is Democracy the Right System? Collaborative Approaches to Building an Engaged RDM Community. Marta Teperek, Rosie Higman, Danny Kingsley

 

Why not…

Variation in the microbiome of the urogenital tract of koalas (Phascolarctos cinereus) with and without “wet bottom”. Alistair Raymond Legione, Jemima Amery-Gale, Michael Lynch, Leesa Haynes, James Gilkerson, Joanne Devlin, Fiona Sansom

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Forgotten classics: Cut and paste embryology

Posted by , on 2 February 2017

Hörstadius, S. 1939. The mechanics of sea urchin development, studied by operative methods. Biological Reviews 14(2):132-179.

Recommended by Bob Goldstein, University of North Carolina at Chapel Hill

 

Sven Hörstadius stands alongside the likes of Boveri, Spemann, Mangold and Driesch as a giant of experimental embryology in the first half of the twentieth century. While his 1950 treatise on the neural crest in vertebrate head development became an early bible for the field, he is probably best known for his work on sea urchins. His 1939 manuscript summarises a whole suite of work from himself and others dealing with various kinds of determination: of the axes of the embryo, of cell fate by instruction or position, and of ‘species character’ by the cytoplasm or the nucleus.

 

Image source – The Embryo Project Encyclopedia

 

The focus is on the purple sea urchin, Paracentrotus lividus, which Hörstadius studied during trips to the Stazione Zoologica in Naples, once a haunt of Driesch and Boveri and still an active centre of research. P. lividus was a particularly useful urchin species because the eggs and early embryos have a vegetal pigment band, allowing polarity to be easily traced. In previous decades the basics of its development had been sketched out, including where successive cleavage planes lie in the cell, the movements of gastrulation, and fate of some blastomeres. However, while fundamental rules of development could be inferred from observation alone, Hörstadius was an experimentalist, and intervened in development in a variety of creative ways to investigate determination. Like Rosa Beddington, subject of the previous post in this series, he was known as an expert dissector: he could isolate blastomeres with fine glass needles, and create chimeras by fusing part of one animal to part of another and placing a small glass ball on top “to give the necessary pressure”. His 1939 paper is full of this sort of cut and paste embryology, and the outcomes are often unexpected (“The following is a very strange phenomenon…”).

 

Stages of early Paracentrotus development, from uncleaved egg to 64-cell stage, from Figure 1, Hörstadius, 1939. Reproduced with permission of Wiley†.

 

The paper also devotes a lot of time accounting for contradictory results from other researchers. In particular, there seems to be a long standing beef with one Leopold von Ubisch, with some wonderfully formal put-downs:

 

“von Ubisch does not admit the possibility that halves of equatorial and subequatorial eggs are different. This is strange…”  (p162)

“von Ubisch concludes that the cytoplasm has no influence on the species character of the skeleton. I do not find this conclusion convincing” (p169)

“The diagram of Fig. 9 has been criticized by von Ubisch. But his objections were, it seems to me, anticipated in the original paper” (p158)

 

As a bleak reminder of the historical context of the work, von Ubisch was forced out of his chair at Münster University for being non-Aryan four years before Hörstadius’ paper came out.

Among the flood of experiments and ideas that Hörstadius describes, some stand out. The first results section addresses the control of spindle position and orientation in the divisions that make the 16 cell embryo with its characteristic micromeres at the vegetal pole. These divisions can be delayed by shaking or adding diluted sea water; once this delay is relieved, the embryo starts dividing again. However, instead of picking up where they left off, the embryos would often skip a cell division such that, for instance, a delayed 4 cell embryo would divide to give micromeres (column B in the figure below).

 

Cleavage in Paracentrotus in normal (A) and delayed conditions (B-F). From Figure 2, Hörstadius, 1939. Reproduced with permission of Wiley†.

 

Hörstadius proposed that the micromere division is determined by the ‘activation’ of material in the vegetal cytoplasm, and that this activation occurs independently of how many cell divisions had occurred. After a certain amount of time, the embryo wants to make micromeres, irrespective of the number of divisions completed, and changes spindle position to do so. There is a kind of ‘cleavage clock’ which sets the type of cell division that occurs next.

The next three sections concern the embryonic axes. Hörstadius began his career under the supervision of John Runnström, who proposed that the sea urchin egg held two gradients, one emanating from the animal and one from the vegetal pole. The gradients “interact mutually and are partially hostile to each other”, and a cell’s fate is dependent on the relative strength of each of the gradients in the cytoplasm it inherits. Before the molecular biology revolution, before experimental and what was then called ‘chemical’ embryology were united, the cytoplasm had “qualities” or “forces” that influenced development.

 

The development of isolated an1 and an2 layers, with or without added micromeres. From Figure 9, Hörstadius, 1939. Reproduced with permission of Wiley†.

 

One of the ways Hörstadius investigated the double gradient hypothesis was to add micromeres (the inheritors of the most vegetal, and hence most ‘active’ cytoplasm) to layers of animal cells. These layers, if isolated and left alone, go on to form useless ciliated balls. Remarkably, add enough micromeres and you could rescue normal development, and gradually increasing the micromere number led to progressively ‘better’ development. Along with the results of various other experiments involving adding bits of one embryo to bits of another, this implied that the amount of animal and vegetal material you start with is crucial to the outcome. To explain these results, Hörstadius

 

“…assume[d] an animal and a vegetative gradient, both reaching the opposite pole and progressively diminishing. The animal and the vegetative qualities or forces have to interact in order to bring about normal differentiations, e.g. vegetative influences are necessary for the formation of ciliated band and stomodaeum, animal ones for gastrulation and skeleton formation, and so on. The differentiation depends – within wide limits – upon the relative amounts of animal or vegetative material present.” (p173)

 

While Lewis Wolpert used these experiments to inform his models of positional information, half a century later the picture had changed as Eric Davidson and others challenged the idea of a double gradient. In the updated model, specification is conditional, and mediated by successive interactions between micromeres and blastomeres, the micromeres having been initially autonomously specified by maternally supplied factors. The model combines modern data on signalling pathways and gene expression with a reinterpretation of Hörstadius’ classic experiments and their insight that cell interactions could direct development.

 

A heterosperm merogone formed from Paracentrotus lividus cytoplasm and Psammechinus microtuberculatus nucleus, from Figure 12, Hörstadius, 1939. Reproduced with permission of Wiley†.

 

The paper ends with the question of the role of the nucleus in inheritance. Hörstadius took up work originally started by Boveri half a century earlier, removing the nucleus from eggs of one species and fertilising them with the sperm of another to make ‘heterosperm merogones’. The nucleus coming from one species, and the cytoplasm the other, he could ask which species the larva ended up looking like, and hence where ‘character’ was determined. In one combination, the merogone followed the characteristics of the species from which the nucleus was taken, but due to high variability in other combinations, Hörstadius had to be cautious in his intepretation:

 

“…the nucleus obviously has a positive effect on the species character. It is to be regretted that the characters in question are not defined sharply enough to permit of a conclusion as to the possible role of the cytoplasm.” (p172)

 

Even treading this lightly, the results are consistent with the work of Boveri, Spemann, Waddington, Wilson and Stevens, all of which put the nucleus, and the mysterious substance contained within it, in the driving seat of development and heredity.

The paper is testament to the power of cut and paste embryology, and the rich potential of the sea urchin embryo as a model. We can leave it Carl Olaf Jacobsen, one of only two graduate students trained by Hörstadius during his long time as a Professor in Uppsala, to summarise his supervisor’s legacy:

 

“…his experiments on sea urchin larvae shed light on a couple of the most central findings in developmental biology, namely that the uneven distribution of the egg-cell contents give rise to early embryo cells with shifting qualities, and that communication between these cells has an essential role in the differentiation process.”

 

Thoughts from the field

Bob Goldstein, University of North Carolina, Chapel Hill

This paper’s a fun read because it’s dense with simple and clever experiments. And many of the experiments built a foundation for our current understanding of how animal development works. But I love it most of all because it’s a great example of old literature that includes questions that we, as a field, forgot were fundamental questions. How does Hörstadius’ cleavage clock work? I think we still don’t know.

 

David McClay, Duke University, North Carolina

Hörstadius’ work was the inspiration for much of what I have done over the past 30 years.  The following information was circulated over the years first by my mentor who had met Hörstadius, and more stories were circulated years ago when there was a festscrhriften thrown in honor of Hörstadius’ life in Stockholm. Unfortunately it was years after his death. Apparently until after his death the Swedes didn’t realize how well known Hörstadius actually was.

The post mentions  that Hörstadius worked under Runnström.  That was true and it was the cause for several things in his life.  The Swedish system had very few professors so Horstadius worked under Runnström for most, if not his entire career.  For that reason the Swedes never considered Hörstadius as particularly famous because he was not in charge. Ruunström was also involved in Hörstadius’ science so I was told.  Runnström was a major proponent of morphogenetic gradients, especially double gradients.  Consequently, the double gradients that are part of Hörstadius’ sea urchin work fit the ideas of Runnström – or perhaps were strongly suggested by him.  Perhaps it was only gossip, but I heard from several senior scientists that Hörstadius never really believed that double gradient nonsense but since he was in Runnström’s lab that was part of the cost.  He was later admitted to the Swedish Academy and to the Royal Academy largely for his work on neural crest, but the sea urchin work has stood the test of time with a greater presence than the neural crest work.

Höstadius was praised for his microsurgical abilities.  He was the only one in the world who could do those remarkable dissections of the tiny sea urchin embryos and the cut and paste experiments were considered amazing feats.  That was how I was initially taught about his work.  He taught himself to dissect on the stage of a compound microscope.  That meant he had to teach himself to move his needles in the opposite direction relative to what was seeing through the objective.  His dissection tray was a piece of photographic film on the bottom of a shallow petri dish.  That was because the photographic film had a coating of gelatin on it which was just thick enough to score a trough in which his embryos would be placed.  Then, all of his dissections were done by hand.  By contrast, I do all the same dissections but in my case I have major help from micro manipulators, a dissection microscope which shows movements in the same direction as what I can see though the objective,  and I can record everything with a camera whereas he had to draw everything.  As I indicated,  he had great hands in addition to a perceptive brain.

 

† Further usage of any Wiley content that appears on this website is strictly prohibited without permission from John Wiley & Sons, Inc. Please contact Wiley’s Permissions Department either via email: permissions@wiley.com or use the RightsLink service by clicking on the ‘Request Permission’ link accompanying this article on Wiley Online Library (www.onlinelibrary.wiley.com)”

 

 

Aidan Maartens

This post is part of a series on forgotten classics of developmental biology. You can read the introduction to the series here and read other posts in this series here. We also would love to hear suggestions for future Forgotten Classics – let us know in the comments box.

 

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Diversity is a good thing: coordination of collective cell migration in angiogenesis

Posted by , on 2 February 2017

Comment on “Asymmetric division coordinates collective cell migration in angiogenesis” Nat Cell Bio, 18 (12), 1292-1301, (2016).

 

Holly E. Lovegrove & Guilherme Costa

Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, Uk

 

Collective cell migration is involved in many biological processes. In particular it is required to build new tissues during morphogenesis and to repair them during wound healing. Cancer cells however also exploit it during invasion of other tissues. In order for a group of cells to migrate together as a coordinated group they must establish a hierarchy of cellular identities, generally thought of as “leader” and “follower” cells (Friedl & Gilmour 2009). How this hierarchy is established and robustly maintained is key to understanding the process of collective cell migration. To examine this, in our recent study we explored the collective movement of endothelial cells undergoing angiogenesis (the generation of new blood vessels from existing ones) in zebrafish embryos. We were particularly interested in how these collectively migrating cells managed to maintain their organisation while undergoing divisions.

 

During sprouting angiogenesis the collectively migrating cells take on the roles of either a leading “tip cell” or a following “stalk cell” (Herbert & Stainier, 2011). The tip cell is the first cell to leave the existing vessel and is highly motile. This is then followed by the stalk cells, which are less motile and go on to form the main trunk of the developing vessel. Previous work has established that this hierarchy is driven by differing levels of Vascular endothelial growth factor (VEGF) signalling, with the tip cells having high levels compared to the stalk cells. This is thought to be established via a Notch/Delta controlled lateral inhibition, whereby tip cells induce a reduction in VEGF signalling in the stalk cells (Herbert & Stainier, 2011).

 

Sprouting angiogenesis in a zebrafish embryo. The “tip cell” (far left) first sprouts from the existing blood vessel and is followed by the “stalk cells”. Blue is DNA and red is the cell membranes

 

During angiogenic sprouting migrating endothelial cells are required to undergo mitosis (Schoors et al. 2015). This presents the cells with a problem, as the two daughter cells must acquire two different migratory profiles, dependent on their resultant positions. The more distal cell must take on the tip cell identity, while the more proximal cell becomes the trailing stalk cell. However, division will partition the components of the VEGF signalling and Notch pathway components, which if equal will presumably induce competition for tip cell identity between the two daughter cells. This would disrupt the migration of the group of cells and ultimately impede angiogenesis. However, far from this, tip/stalk cell identities are actually established almost instantaneously after division, much faster than notch/delta mediated lateral inhibition is thought to take (upwards of 5 hours) (Matsuda et al. 2015; Bentley et al. 2014).

 

After division cells immediately display distinct tip and stalk cell behaviours. Costa et al., (2016)

 

The question – How are the tip/stalk identities of collectively migrating endothelial cells re-established so quickly after mitosis?

Computer modelling suggested that the answer to this question could be that these cells undergo a form of asymmetric cell division and produce daughters of different sizes. The model predicted that a larger daughter cell would inherit more of the VEGF signalling machinery, giving it higher levels of VEGF signalling and thereby establishing it as the tip cell. Live imaging of zebrafish angiogenic endothelial cells revealed that indeed the most distal daughter cell (the tip cell position) is on average 1.8-1.9 times larger than the more proximal daughter cell (the stalk cell position). Furthermore, the size of each daughter cell was shown to be proportional to its migratory speed, meaning that sister cells that had the biggest difference in their size also have the biggest difference in their speeds. Furthermore, in vitro work also demonstrated that larger cells inherit a larger proportion of VEGF receptor mRNA, as well as having higher levels of VEGF signalling. In order to demonstrate that these differing levels of VEGF signalling were necessary to define post-mitotic tip/stalk cell identities, zebrafish embryos were treated with low levels of a drug that blocks VEGF signalling. This low dose didn’t inhibit signalling altogether but prevented any cell from signalling at the levels necessary to be a tip cell. Under these conditions both daughter cells assumed stalk-like identities after mitosis.

 

A) The divisions of zebrafish angiogenic endothelial cells are asymmetric; one cell (the tip cell, cell 1.1) is larger than the other (the stalk cell, cell 1.2)
B) The size of a cell is proportional to its speed of migration. Costa et al., (2016)

 

How might the asymmetry in daughter cell size be achieved?

Preliminary data suggests that the size asymmetry seen in angiogenic endothelial cells is (at least in part) generated by the positioning of the mitotic spindle towards the proximal pole of the cell (Costa et al. 2016). Thereby shifting the division plane away from the volumetric centre of the cell. Other classical asymmetric cell divisions also result in cells of different sizes, for example Drosophila neuroblasts and one-cell C. elegans embryos, though the role of this asymmetry has not been extensively explored (Cabernard et al. 2010; McNally 2013). However some clues may be gleaned as to how angiogenic endothelial cells manage to position their mitotic spindles such that two differently sized daughters are produced. A canonical set of proteins is known to generate the membrane associated pulling force that acts upon mitotic spindles. Partner of Inscuteable (Pins) (LGN in Drosophila and GPR1/2 in C.elegans), anchored at the membrane by Gαi (GOA-1 and GPA-16 in C.elegans), binds to Nuclear mitotic apparatus (NuMA) (Mud in Drosophila and LIN-5 in C.elegans), which in turn binds to the dynein/dynactin complex, this then pulls on the plus ends of astral microtubules (Bergstralh et al. 2013). Asymmetric enrichment of this complex can cause the spindle to be pulled towards one side of the cell, such as in the one-cell C.elegans embryo (Kiyomitsu, 2015). However, it remains to be seen whether the spindle orienting machinery is involved in positioning the mitotic spindle of angiogenic endothelial cells.

 

Downward movement of the mitotic spindle positions the plane of division such that 2 differently sized daughter cells are produced. Costa et al., (2016)

 

Asymmetric cell division is a well-described phenomenon traditionally thought of as a process employed by cells to enable them to generate cells different from themselves. An asymmetric inheritance of fate determinants or a position dependent asymmetry in external cues normally results in daughter cells becoming two different cells types. Size asymmetry (and a resultant asymmetry in signalling strengths) between daughter cells offers a simple way of introducing subtle heterogeneity into a population of a single cell type. Furthermore, if it is controlled so that the larger and smaller cells are positioned specifically, patterns (such as leading and following cells) can be produced. Further work is needed to elucidate the mechanism behind this new form of asymmetric division and it will be interesting to see whether other collectively migrating systems, or indeed any other cell types, undergo similar divisions.

 

 

References

Bentley, K., Harrington, K.I. & Regan, E.R., Can active perception generate bistability? Heterogeneous collective dynamics and vascular patterning. ALIFE http://dx.doi.org/10.7551/978-0-262-32621-6-ch053 (2014)

Bergstralh, D.T., Haack, T. & St Johnston, D., 2013. Epithelial polarity and spindle orientation: intersecting pathways. Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 368(1629), p.20130291.

Cabernard, C., Prehoda, K.E. & Doe, C.Q., 2010. A spindle-independent cleavage furrow positioning pathway. Nature, 467(7311), pp.91–94.

Costa, G. et al., 2016. Asymmetric division coordinates collective cell migration in angiogenesis. Nature cell biology, 18(12), pp.1292–1301.

Friedl, P. & Gilmour, D., 2009. Collective cell migration in morphogenesis, regeneration and cancer. Nature reviews. Molecular cell biology, 10(7), pp.445–457.

Herbert, S.P. & Stainier, D.Y.R., 2011. Molecular control of endothelial cell behaviour during blood vessel morphogenesis. Nature reviews. Molecular cell biology, 12(9), pp.551–564.

Kiyomitsu, T., 2015. Mechanisms of daughter cell-size control during cell division. Trends in cell biology, 25(5), pp.286–295.

Matsuda, M. et al., 2015. Synthetic lateral inhibition governs cell-type bifurcation with robust ratios. Nature communications, 6.

McNally, F.J., 2013. Mechanisms of spindle positioning. Journal of Cell Biology, 200(2), pp.131–140.

Schoors, S. et al., 2015. Fatty acid carbon is essential for dNTP synthesis in endothelial cells. Nature, 520(7546), pp.192–197.

 

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Reviews Editor, Development – maternity cover

Posted by , on 1 February 2017

Closing Date: 15 March 2021

Reviews Editor, Development – maternity cover
Based in Cambridge, UK

 

We are currently seeking applications for the role of Reviews Editor at Development. This is a temporary position (maternity cover) anticipated to last up to 12 months, starting June 2017.

 

Joining an experienced and successful team, this is an exciting opportunity to make a significant contribution to one of the major journals in the field of developmental biology. Development publishes primary research articles, reviews and other front section content across the breadth of the developmental biology and stem cell fields.

 

Applicants will hold a PhD in developmental or stem cell biology. Post-doctoral and/or previous editorial experience is desirable, although we will provide full training.

 

Core responsibilities:

  • Commissioning, handling peer review and developmental editing of material for the front section of the journal
  • Representing the journal at international conferences and within the wider scientific community
  • Writing press releases, article highlights and material for Development’s community website ‘the Node’
  • Creative involvement in the journal’s development

 

The successful candidate will have a broad interest in science, the scientific community and publishing. Excellent interpersonal and literary skills, enthusiasm and commitment are also essential requirements for the position.

 

The Reviews Editor will work alongside an experienced in-house team, including the Executive Editor and current Reviews Editor, as well as with our international team of academic editors.

 

This maternity cover position provides an excellent opportunity to gain experience on a highly successful life-science journal, and offers an attractive salary and benefits. The position is full-time and will be based in The Company of Biologists’ attractive modern office on the outskirts of Cambridge, UK.

 

The Company of Biologists (biologists.com) exists to support biologists and inspire advances in biology. At the heart of what we do are our five specialist journals – Development, Journal of Cell Science, Journal of Experimental Biology, Disease Models & Mechanisms and Biology Open – two of them fully open access. All are edited by expert researchers in the field, and all articles are subjected to rigorous peer review. We take great pride in the experience of our editorial team and the quality of the work we publish. We believe that the profits from publishing the hard work of biologists should support scientific discovery and help develop future scientists. Our grants help support societies, meetings and individuals. Our workshops and meetings give the opportunity to network and collaborate.

 

Applicants should send a CV to recruitment@biologists.com, along with a covering letter that summarises their relevant experience, why they are enthusiastic about this opportunity, and their current salary level. Applicants should be eligible to work in the UK and should be able to travel internationally.

 

Applications should be received by February 28th 2017, though we may be able to consider later applications.

 

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