I’ve no doubt that this is what they’d say:

Or maybe this is what they really sound like and Sir David Attenborough refused to share this with us on the BBC.

Just for fun! I bet UK residents are very familiar with BBC One’s Walk on the Wild Side. Now to enlighten the rest of the world..

(3 votes)

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The early embryology of the chick
Coffee and Sci(ence) features the 90-year-old book “The Early Embryology of the Chick” by Bradley Patten. The book is now out of copyright, and you can find the whole thing online at the Internet Archive.

“This book on the development of the chick has been written for those who are beginning the study of embryology and has accordingly been kept as brief and as uncomplicated as possible. Nevertheless it is assumed that the beginner in embryology will not be without a certain back-ground of zoological knowledge and training. He may reasonably be expected to he familiar with some of the aspects of evolution and heredity, with the recapitulation theory, the cell theory, the nature of the various types of tissues, and the more general phases of the morphology of vertebrates. “ – Bradley Patten, from the introduction to “The Early Embryology of the Chick” (1920)

Interview with Sir John Gurdon
After that trip back in time to the 1920s, let’s jump forward almost a century, to December 2010, when the Wellcome Trust interviewed Sir John Gurdon.

“Among the clutter of John Gurdon’s brightly lit Cambridge office sits a picture frame, displaying a small scrap of browning paper from an early school report. It reads: “I believe he has ideas about becoming a scientist…this is quite ridiculous…it would be a sheer waste of time, both on his part and of those who have to teach him.”
Professor Sir John Gurdon is now a knight of the realm, a Fellow of the Royal Society, a former Governor of the Wellcome Trust and the scientist who kickstarted the field of cloning. ” – From the Wellcome Trust interview

The Lab
The Lab is a “choose your own adventure”-style game from the Office of Research Integrity, in which you pretend to be one of four characters (grad student, postdoc, PI, or research integrity officer) and try to make the right decisions to prevent the lab from being shut down after a case of research misconduct.
It’s effectively a movie, of which you only see the scenes you choose. The Lab is extremely well done and fun to play, and the acting is far better than most educational videos, but wait until the end of the day, or your lunch break, to play, because it takes quite a while.
I played as the PI, and made a crucial mistake. Whoops! This is why I don’t have my own lab… But the game is forgiving, and let me go back to that point to see what would have happened if I made another choice. If only real life worked that way!

(3 votes)

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During the first year of my PhD, I undertook a small rotation project in the lab of Dr Kim Dale, doing some work with the chick embryo. I did this project to try something a bit different. All my work up until this point had been sub-cellular and mostly within the nucleus. Who knew there were whole tissues and even whole organisms to study? Not me. I had never considered it before. I was all set to cure cancer during my PhD and then along came the chick embryo. I loved the project (and Kim) so much that I returned to her lab to complete the remaining three years of my PhD. I didn’t even know what mesoderm was when I started, how we laugh now and thanks Kim for bringing it up at my viva presentation (it’s not forgotten).

I absolutely loved my experimental work and Kim was an amazing supervisor. During my first year I had some very beautiful results and was still all set on undertaking a career in research. To be honest, I didn’t really understand why anyone wouldn’t want to run their own lab (and obviously win a Nobel prize for being so fabulous). They said, “you’ll understand  one day”. They were right. I have to say that while I loved doing my experiments the level of anxiety and distress caused by the rest of academic life was just not worth it for me. The constant pressure and the need to commit so much of my soul to the work was not something I felt I could maintain for the rest of my life. I soon became aware that there would never be a point where the pressure lessened, there would always be papers, grants, fellowships, tenure, more papers, more grant applications and more rejection. Not an enticing prospect. I liked finding out how things worked, not the politics that goes with establishing a career in academia. It doesn’t pay well enough to make up for it. I also became aware how narrow the opportunities were to establish your own lab. Only one in ten post docs make it and the thought of what happened to the other 90% terrified me. And most of the 10% then have go through tenure (yuck). So I decided to get out before it was too late and I was doomed to eternal postdocing.

I think that I had made a firm decision NOT to be an academic researcher at the start of my third year. Then the question was, what the hell do I do now? All my dreams and hopes had changed. I also didn’t want to go into industry. So what else was there? I had no idea. Getting help with this was quite hard. Academics, at least from my own encounters with them, tend to have only experienced an academic life and therefore don’t know what’s required to move out of it in many cases. I know this is very generalist but it is certainly how I felt at the time. Kim was fantastic and very supportive however. When I told her my decision, she did all she could to help and never once made out that it was the wrong decision (although she did say it was a loss for science but I am very much still involved with science so I guess it depends how you look at it). She was happy for me to do any skills courses I wanted and did all she could to help me progress in whatever career I chose.

So I added to my work load and took on as many other activities as I could. I starting organising scientific meetings with my best friend who works at the Roslin Institute. Soon the first Scottish Chick Symposium was born and there have now been five meetings. I also did plenty of generic skills courses in time management, communication skills, presentation skills, the list goes on and on. I put myself forward for presentation at every opportunity and went to as many conferences as I could to network to the max. This involved applying for funding, making lots of posters and generally staying up really late (best networking time is 1-3am I find). I also did a lot of public engagement work, getting the whole lab involved in events at science centres, writing articles and doing some free lance writing for The Primitive Streak project. I also did a three month science policy internship at the Academy of Medical Sciences in London.

So basically I was knackered, but still managed to complete a successful PhD and developed a vast array of skills. I’d also learnt a lot about what I enjoyed. I found that I actually really liked working in an office. I liked feeling like part of a team, where you didn’t feel possessive over your work and everyone helped each other out. I also rekindled my love for a wide variety of science. I hadn’t realised how narrowly focussed I had become. It turns out somites aren’t the only area of science! They had ruled my life for four years so regaining perspective was wonderful. I also found an office job to be extremely varied. Much more so than the lab where the same experiments are done again and again (I still don’t know if I will ever miss cutting PSM explants or not, it might take a lot of years). I also was rather fond of project management. I really enjoyed organising things and loved the challenge and variety that this could bring. I also discovered that outside of academia, no-one really cares about your publications! Or at least there isn’t the same requirement for them. They mean the world to you at the time but trust me, your skills are so much more important when you’re leaving academia. And I don’t mean lab skills, I doubt anyone will ever ask me to dissect some PSM explants in a job interview at any point.

So, I’d done my PhD and an internship. I then returned to the only place I would consider doing a postdoc, in Kim’s lab. I wanted to get the project ready to pass on and get a review paper written, so I went back for six months. This turned into ten months while I was searching for jobs. This takes such a long time I can’t tell you. Each application form would take up to four hours. You HAVE to tailor each one or there’s no point writing it. Whoever looks at it will just stick it in the bin if you just witter on about the details of your lab project. Why do you want that particular job and why are you the best person to do it? That’s all they want to hear or you won’t get an interview. This is a big learning curve, you can’t just have a CV and send it around. I don’t think that works in academia either by the way. Having seen the selection process in Kim’s lab, I know that sending out your CV with loads of non-specific info just makes it look like you don’t really care about the job. Which is likely to be true. Those ones are canned immediately.

I digress, sorry. It’s just an important point that’s all. So, I had filled out more application forms than I care to mention. I wasn’t sure if what I was applying for at that point was for me, hence the lack of interviews I guess. However, I did find searching for jobs and applying absolutely invaluable as I started to open my eyes to the number of possibilities out there. I was hoping that a policy job would come along but there aren’t so many in Scotland and I didn’t want to move to London and my husband would have divorced me if I’d asked him to go there (did I mention I also planned my wedding and got married during my third year?). Then one day I saw a psci-com post (a website for science communication that has loads of jobs advertisements in all manner of scientific fields) that was advertising for a Science and Interpretation Officer role at Glasgow Science Centre. The role would be to undertake some research to help put together an exhibition about health and wellbeing. This sounded ideal, I loved the activities I had done in science centres and it would involve project management and lots of interaction with researchers. The only problem was, the contract was only for 12 months and Glasgow is 60 miles away from where I live in Perth. But I thought, ‘well, you can’t have everything’ and applied.

I didn’t initially get invited for interview. I found that out when I phoned to ask how my application had gone. The reason was I had a lack of experience in developing exhibitions (actually I didn’t have any experience in this but what can you do). I was very disappointed and asked if someone there could perhaps phone me back and discuss my application with me. I explained that it was the ideal job for me and I felt I had a lot to offer. I really wanted to know what those who had got interviews had in their applications that I didn’t (other than direct experience). I heard back from them and they’d changed their minds about interviewing me after looking at my application again. I also had a wonderful letter of support from Jon Urch, who runs all of the science communication activity for the University of Dundee, which I think helped massively. I only had a couple days notice for the interview but said I would be delighted to attend. At this point I knew I was on the bottom of the list going into the interviews, their last choice. So I didn’t expect much but was very keen to get some interview experience.

I didn’t think the interview went terribly well, but then I always think that. It’s really hard to know what they pick up on in the interview or what they’re looking for. I was more myself than usual in the interview so I guess I was more relaxed. I just answered their questions as best I could and told them about the stuff I had done during my PhD (the non-somite related stuff) and how I went about work in general. It must have done the trick as a few days later they asked me to submit a portfolio of my written work (in hind-sight I wish I had done this before being asked but never mind) and shortly after that I got a phone call offering me the position. I was delighted and after negotiating salary and start date I was set to start. Since then they’ve told me a big part of their decision to offer me the position was based on the fact that I had done a PhD, I had experience of doing research and lots of reading and doing it quickly. They also felt I had the confidence and experience to go and speak to top academics in all manner of fields.

I’ve been there since October. It’s fantastic. I’ve read about research ranging from prosthetic limb design to stem cell research. I’ve made rockets to see how far I could make them fly using a plastic bottle as a launcher and made drugs out of Lego to prototype some ideas of how to engage the public with the drug discovery route. It has to be said that the commute is horrendous but I work from home a lot and travel around Scotland a bit meeting researchers so I don’t have to do it every day. I love the job I am doing. I did have to sacrifice money and travel time but it has been more than worth it. I feel like I am where I should be now and vitally, when I look for my next step, I will have some real job experience to add to my application. There is so much I can do with the skill set I have developed and my PhD was crucial to that development. I don’t regret having done a PhD at all, it’s the most character building thing I’ve ever done!

My advice for anyone looking to take a similar leap out of the lab, start NOW. You already have by reading this overly long blog. Think about what you enjoy doing and start filling in some application forms. You will have to be prepared to put in some serious hours doing stuff on top of your lab work but at the end of the day, if you don’t want to be where you currently are in a year’s time, you will only change it if you make it happen. Think outside of the lab, if you don’t plan to be an expert cryosectioner for the rest of your days then that’s not the most important skill to perfect while you’re in the lab. And I’m not suggesting give up on your bench work and go and do some skills courses. You need to have a successful project in the lab but that success goes beyond doing 5000 western blots.

(8 votes)

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Young Embryologist Network Meeting (YEM:2011)
Friday 6th May 2011 at King?s College London.
Meeting registration, talk and poster submission – now open.
Website: www.ucl.ac.uk/cdb/yen/abs

The 3rd Young Embryologist Meeting will take place on Friday 6th May 2011 at King’s College London (Guy’s Tower, Floor 30). There will be a keynote lecture delivered by Sir John Gurdon, talks, poster session and a careers session with a panel of three PIs (Prof. Claudio Stern, Prof. Jon Clarke and Dr. Karen Liu).

This unique meeting is run by PhD and Post Docs at UCL, King’s and NIMR and aims to create a more interactive research community. Everyone is welcome to attend and the meeting is free and open to all.

We hope the meeting will provide a platform for young researchers (preference is given to PhD and Post Docs) to present their work in a series of 20 minute talks and a poster session. We will favour the diversity of topics and models in the field of embryology (previous meetings have included talks on neural crest migration, patterning of the cerebral cortex, neural tube morphogenesis, limb development and involved work using mouse, chick, frog, fly and zebrafish models).

Our main interest is to generate a space where students, postdocs, PIs and everyone else can listen to other people’s work and to discuss different topics of developmental biology in a relaxed setting. Ultimately we want to strengthen the recently started Young Embryologist Network to enhance the research environment for embryologists, so please come!

If you are interested in giving a 20 minute talk or presenting a poster please see the website for details & send an abstract of your proposal to: youngembryologistnetwork@gmail.com
(or see www.ucl.ac.uk/cdb/yen/abs ). Deadline for submissions is March 31st 2011.

If you want to get more out of your research, meet fellow researchers, and get new ideas then join the Young Embryologist Network (YEN) mailing list for updates on future events: www.ucl.ac.uk/cdb/yen/abs

& join the YEN facebook group: http://www.facebook.com/home.php?sk=group_162682597092683

(4 votes)

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When Eva approached me about contributing to this series about how one goes from a PhD in developmental biology and ends up in a non traditional academic career path, I thought it would be a great opportunity. I love my job as an educational game designer at Spongelab Interactive, so why not share the winding path I took to get here?

For as long as I can remember, I’ve always loved science, particularly the way you could ask any question you wanted and then figure out how to determine the answer. When I was 10 that meant ‘do walnut shells float’ and when I was 25 that meant ‘how does an epithelial lumen form between photoreceptor cells in a Drosophila retina.’ I did my undergrad at the University of Toronto at Mississauga, hoping to get into the Forensic Science program with biology as my major. Along the way I had some amazing hands-on research opportunities that really opened my eyes to research as a career and from then on I had my sights set on a PhD, and on becoming a PI.

In between dissecting thousands of retinas during my PhD at the University of Toronto, I joined a science outreach organization called Let’s Talk Science. It was likely a catalyst for where I am now, but at the time, I was completely oblivious of its potential impact and just thoroughly enjoyed doing hands-on activities with kids. I found that I loved talking to people about science and the bonus outcome was the more I did it, the less nervous I was giving talks (something my future self would thank me for when I presented to a room of 800 scientists at ASCB). I enjoyed the challenge of taking my research and making it accessible to anyone, though 5 year olds were my favourite. Having a serious conversation with a 5 year old who made the connection ‘so if you are trying to make your blind fruit flies see again, does that mean my grandma might be able to see again too one day?’ was unforgettable. Yes it may be a bit more complicated then that, but it was pretty close to what I wrote in the ‘future applications’ section of grants.

Road Trip! Doing outreach on the road meant casting agarose gels in hotel rooms and posing with many interesting signs.

I took pride in demystifying who a scientist was and what they did. I took part in remote outreach activities where we went to small towns and did career talks, often with students who had discounted science as a career because it was ‘too hard’ or ‘too abstract’. Yet when I put up electron micrographs of wild-type and mutant retinas, it was almost always the most disengaged student who pointed out the differences. My goal was to show them that my process as a scientist was just like that – I screened different types of flies looking for differences, then designed experiments to try and figure out what was causing those differences. Some people enjoy the prestige and awe that being a ‘scientist’ evokes in people – I enjoyed breaking down those barriers and making science accessible to anyone.

It never occurred to me that there might be a way to combine my interest in communicating science with my academic background – mostly because I never looked beyond the path of becoming a PI. Fortunately (or unfortunately depending on when you asked me at the time), as I was coming to the end of what felt like the never-ending thesis, I was burnt out. So burnt out that I began to question whether I still had the drive and passion towards pursuing the academic life I had dreamed of. I had invested so much in my PhD: getting the right scholarships, giving as many talks as possible, narrowly avoiding being scooped and getting the high-impact paper, all to put me in the best position come post-doc time. And it was worth it, as I had my choice of post-doc offers, and I chose the one that would hopefully give me the best shot at landing a PI position one day. But the last year of trying to finish that ‘one last experiment’ took its toll on me and I no longer had the same motivation and ambition that I felt I needed to be successful. So I made a decision. I gave up my post-doc and started looking for other opportunities. I gave myself a year to do something different, something hopefully science related to reenergize my love of science, knowing that I could re-interview for post-docs again in year if that was what I wanted.

So how did I end up designing educational games about biology for Spongelab Interactive? I started talking to people, looking for different opportunities and along the way, I found an ad in my department. They were looking for a graduate student to help write grants and contribute to their games about biology. It sounded too perfect and strange to be true. It was the first CV I ever sent out that included my scholarships and publications as well as my video gaming experience (both quite impressive in their own right). I started out doing freelance work, primarily on a platform called Genomics Digital Lab, which went on to win awards from NSF and be published in Science 2 years in a row for best Interactive Media in their International Science & Engineering Visualization Challenge, as well as a United Nations World Summit Award for best e-content. I applied for and secured funding to turn my freelance position into a full-time position, and two years later I’m still happily using my love of communicating science, combined with game-based learning to engage students and the public in learning about science.

What I enjoy most about my job is how different every day can be. We’re a small company, so I get a chance to do everything from sales and marketing to debugging and QA. I work with programmers, animators, and illustrators, to create engaging and educational science tools. Because we have such strong science backgrounds here, we really do focus on making sure everything scientifically accurate, but also stunning and beautiful to look at. The best parts of my job are when I get into ‘creative scientist mode.’  The first project I was involved in from start to finish was a web-based scavenger hunt on the ‘History of Biology.’ It involved everything from researching the scientists, their discoveries, the state of society at the time, then building a storyline with 14 missions with science-based puzzles to solve.

How many scientists do you recognize from the History of Biology?

In addition to creating engaging new products, I still get to do some of my favorite things from grad school. I participate in outreach both in the classroom and in other initiatives such as Microsoft’s Digigirlz (careers in technology seems just as ‘hard’ to students as science is). I am still connected with academic research as we partner with researchers on the effectiveness of game-based learning, and write collaborative research grants, something I’ve really enjoyed doing.

I’m the first to admit that I never expected to end up designing games about science. This job didn’t even exist 3 years ago, so it definitely wasn’t something I could have planned for. And yes, it was a shock to my colleagues when I announced I wasn’t pursuing a post-doc (at least for the time being), and was going off to create biology video games. They got over the shock pretty quickly, particularly after introducing them to Transcription Hero – where they could upload any gene from Genbank, pick their own music, and race against the native RNA polymerase to transcribe their gene!

Students of all ages love Transcription Hero, and it’s a great attention grabber at conferences, but there’s nothing like going head-to-head with your labmates and their favourite genes.

Taking the chance on Spongelab Interactive really turned out to be the perfect place for my education, outreach experiences, and hobbies to intersect. A PhD in developmental and cell biology really is essential in understanding the science I’m trying to communicate and the research, analytical, and problem-solving skills from grad school are essential working in an industry where you’re leading the way with new research and technology innovations. Without my science outreach experiences where I learned to effectively communicate science to any audience, it would be hard to turn the science concepts into engaging and interactive games. And who knew, that my geeky video and computer game playing experiences would be key in understanding what makes a game fun. This is a fast-growing industry, especially as technology and education continue to converge. Companies are always looking for the right people who have a strong science background and great written communication skills – it’s a particular skill set that definitely seems to be geared towards Masters or PhD students for those that are interested in doing something a little different.

It’s been over 2 years since I made that decision to try something else for a year. I often get asked: do I have any regrets?  I don’t, none at all. I made the right decision at the time, knowing that I could always make another decision if things didn’t work out. I know that if I did have regrets, I’d be back doing a post-doc somewhere, doing some amazing science that I was passionate about.

(7 votes)

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With so much research focusing on stem cells, I’ve been wondering lately whether researchers are overlooking other important, multipotent cell groups, specifically what are called “progenitor” cells. But then another part of me wonders whether these two groups are so very different from each other. Technically, the main difference between stem cells and progenitors is their lifespan, with progenitors’ being much shorter, but the line here seems blurry; most adult stem cells cannot be cultured for extensive amounts of time before they differentiate or senesce.

I was reminded of the issue of stem cells versus progenitors by a paper that came out earlier this month in The Journal of Clinical Investigation that showed, surprisingly, that patients with androgenic alopecia (AGA), or male pattern baldness, had a normal number of hair stem cells in their scalps, but a depleted number of different hair progenitor cells. The progenitors now look like a likely culprit for AGA. It’s been well-studied how stem cells in hair follicles give rise to new hairs over time, and it’s known that progenitors derived from these stem cells play key roles in this process, but it had not been studied with relation to AGA previously. It’s possible that the stem cells in bald AGA scalps are somehow dysfunctional or inactivated, and this could cause the loss of progenitor cells, but it still needs to be looked into (If you’d like to read more detailed coverage of this paper, I wrote a technical blog post about it on my blog All Things Stem Cell and a layman article on it for my column Biology Bytes.)

I wonder what would have happened to this recent study if when the researchers had found out that the number of hair stem cells was the same in haired and bald scalps, they then moved on to investigating other, maybe non-cellular suspects, without looking at the progenitors. Perhaps they would have then discovered a molecular abnormality in the stem cells, and then suspected the downstream progenitor groups. I just can’t help but wonder how many other diseases and biological phenomena have been investigated with a primary focus on the stem cells involved, when in some cases the progenitors may be a better initial indicator for what’s changed in the system. Or maybe using the terms “stem cells” and “progenitors” is really splitting hairs; stem cells vary significantly in potency and proliferation capacity from group to group, so maybe we should just expand the already expansive term “stem cells” to encompass a broader range of cells. While I like to think that a cell type’s name doesn’t affect whether a researcher studies it, I’d imagine it’s easier to get funding for “stem cell” research than “progenitor cell” research (or, with some funding agencies it may be the other way around), and this may definitely affect a researcher’s focus with funding as tight as it is.

(6 votes)

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We’ve been busy – both behind the scenes and in plain view – so it’s time for another update.

Contest
We’re currently running our very first contest, with a prize generously donated by TipArt. If you’d like to win a chance to commission some unique science-themed art, remember to send in your images before the end of this month.

Loading issue and other technical stuff
We’re aware of the slow loading front page, and are actively looking for someone to fix this, as well as other issues. Preferably a UK-based web developer with knowledge of PHP/Wordpress. If you know anyone fitting that description, send them our way!

Reporting comments
We’ve removed the link to “report comments” because it was attracting too much random and unnecessary clicking (making us have to re-approve every single comment on the site – no exceptions.). Have a look at the Help Page to see what to do if you ever come across any offensive/spam content on the Node.

Coming up
We’re currently working on getting author biographies with every post. It will use the text you have entered in your profiles, so have another look at that one of these days and make sure it’s up to date, and something you wouldn’t mind showing up under you posts. More on this later.

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What I love about developmental biology is the collaborative nature of the field.   The vast majority of biologists feel that by sharing ideas, data, and reagents, we can learn more than if we were all to work alone with blinders on our heads.  A recent paper in Development puts forth a hypothesis about embryonic stem cell origin.  Hopefully, the ideas presented will serve as food for thought for the stem cell field and lead to a new understanding about ES cells.

Embryonic stem (ES) cells are valuable in the study of human diseases and development due to their pluripotent nature, and have the potential for treating disease and replacing damaged tissue.  Because of their amazing potential, it is crucial to understand how and when pluripotency occurs, and how stem cells can be cultured.  Naïve pluripotency occurs twice during development—first in early epiblast tissue and again in the germ cell lineage—and this reflects the relationship between pluripotency and the mammalian germ line.  The recent Hypothesis paper by Nichols and Smith suggests that ES cells could be cultured via two routes to reach naïve pluripotency—directly from early epiblast tissue or during the specification of primordial germ cells in culture.

Images above show an early mouse embryo (left) and a colony of ES cells growing on a layer of fibroblast cells (right).  In the embryo, epiblast cells are red, hypoblast cells are green, and trophectoderm is blue.

For a more general description of this image, see my post on EuroStemCell, the European stem cell portal.

Nichols, J., & Smith, A. (2010). The origin and identity of embryonic stem cells Development, 138 (1), 3-8 DOI: 10.1242/dev.050831

(4 votes)

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Here are the highlights from the current issue of Development:

From pluripotent to pancreatic fates

A reliable method for generating insulin-producing β-cells from human pluripotent stem cells (hPSCs) would provide new therapeutic options for people with diabetes. So far, no-one has developed such a method but, on p. 861, Gordon Keller and colleagues provide new insights into the complex signalling networks that underlie β-cell differentiation. The generation of β-cells from hPSCs requires efficient endoderm induction followed by patterning and specification to a pancreatic fate. The researchers show that the duration of nodal/activin A signalling plays a pivotal role in endoderm induction and that WNT signalling enhances the subsequent development of pancreatic lineage cells. Inhibition of BMP signalling at specific stages is also essential for the generation of insulin-expressing cells. Importantly, report the researchers, optimal stage-specific manipulation of TGFβ and WNT signalling yields cell populations that produce insulin at levels similar to those made by the pancreas. However, because these cells also make other hormones, further studies are needed to discover how to convert these polyhormonal cells into functional β-cells.

Full Fat signalling in mammals: Dchs1 and Fat4 pair up

In Drosophila, Dachsous and Fat act as ligand and receptor, respectively, for a signalling pathway that regulates planar cell polarity (PCP) and transcription via the Hippo pathway. Mammals encode multiple Fat and Dachsous proteins but do they have an equivalent Fat signalling pathway? On p. 947, Yaopan Mao and colleagues report that murine Dchs1 and Fat4 function as a ligand-receptor pair during development. The researchers show that Dchs1 and Fat4 single mutants and Dchs1 Fat4 double mutants exhibit similar phenotypes. These phenotypes include the formation of kidney cysts and cochlear defects, suggesting that Dchs1-Fat4 signalling influences PCP in mice. However, the researchers also identify non-PCP-related requirements for Dchs1-Fat4 signalling in the development of other organs. In particular, they show that Dchs1 and Fat4 are needed for growth, branching and cell survival during early kidney development. Together, these results identify Dchs1 and Fat4 as a ligand-receptor pair for mammalian Fat signalling and identify new requirements for Fat signalling in multiple organs.

Capicua mediates response to RTK signalling

Receptor tyrosine kinase (RTK) signalling pathways regulate many developmental decisions, but how RTK signalling controls the expression of its target genes in different contexts is poorly understood. Here, Gerardo Jiménez and co-workers reveal that octameric DNA-binding sites for the transcriptional repressor Capicua (Cic) are critically involved in RTK signalling in Drosophila (see p. 915). They show that the regulation of terminal gap gene expression by the Drosophila RTK Torso in early embryos depends on octameric Cic-binding sites in the enhancer region of the gap gene huckebein. Moreover, these Cic-binding motifs are essential for recruitment of the Groucho co-repressor to the huckebein enhancer in vivo. Cic-binding sites also respond to EGFR RTK pathway activation in the embryonic neuroectoderm and in the developing wing. Finally, using synthetic enhancer constructs, the researchers show that Cic-binding motifs provide the regulatory information necessary to translate RTK signalling inputs into precise transcriptional responses in different tissues. Thus, they conclude, octameric Cic-binding motifs are general response elements for RTK signalling in Drosophila.

A new spin(dle) on stem cell division

Stem cells divide asymmetrically to balance self-renewal and differentiation, thereby maintaining tissue homeostasis. But what coordinates the divisions of multiple stem cell populations in complex tissues? To address this question, Yukiko Yamashita, Alan Hunt and colleagues (see p. 831) have been studying stem cell division in the Drosophila testis, which contains both germline stem cells (GSCs) and somatic cyst stem cells (CySCs). GSCs divide asymmetrically by maintaining a fixed cell polarity within the stem cell niche. Now, the researchers use time-lapse live imaging to show that CySC asymmetric division involves the repositioning of a randomly located mitotic spindle during or near anaphase onset. Spindle repositioning, they report, requires functional centrosomes, the motor protein Dynein and the actin-membrane linker Moesin, and is required to achieve the high-fidelity asymmetric CySC divisions that maintain both GSC and CySC numbers. The researchers speculate that the use of multiple mitotic schemes may be a general mechanism whereby divisions of different stem cell populations are coordinated in complex tissues.

Eyeing up neuronal circuits

The Drosophila optic lobe shares many characteristics with mammalian visual systems and might provide a powerful model for investigating the formation of visual processing circuits. Little is known, however, about the mechanisms that create neuronal diversity and organise neuronal circuits in the medulla, the optic lobe’s primary region. Now, on p. 983, Makoto Sato and colleagues describe the key features of the developing fly medulla. They show that, during larval development, the medulla is subdivided into concentric zones that are characterised by the expression of the transcription factors Drifter, Runt, Homothorax and Brain-specific homeobox. The birth order of the medulla neurons correlates with the expression pattern of these factors, they report, and each neuronal type exhibits an extensive but defined pattern of migration that disrupts the concentric zones during early pupal development. These results, and those of clonal analyses, lead the researchers to suggest that the concentric zone genes may form a genetic hierarchy that specifies neuronal identity and establishes neuronal circuits in the developing medulla.

Marking up germline imprints

Genomic imprinting – epigenetic modifications that ensure that certain genes are expressed from only one of the two inherited chromosomes – is crucial for normal development. Mammalian imprinted genes are associated with differentially methylated regions (DMRs) that are CpG methylated on one parental chromosome. At least 21 DMRs become methylated in the mouse germline and, on p. 811, Hiroyuki Sasaki and co-workers analyse a panel of these gametic DMRs. The extent of methylation of these DMRs differs significantly from that of embryonic DMRs, they report, suggesting that gametic DMRs should be used to identify the features that establish imprinting in the germline. They also show that maternal gametic DMRs appear as unmethylated islands in male germ cells, and unexpectedly identify widespread oocyte-specific non-CpG methylation. Finally, they report that DMR methylation changes dynamically during early development, indicating that DMRs are not fully protected from preimplantation epigenetic reprogramming. These results underscore the importance of using gametic DMR sequences for the study of imprint establishment.

Also…

PAR proteins are conserved regulators of cell polarity, and recent studies, reviewed here by Jeremy Nance and Jennifer Zallen, have identified elaborate links between PAR proteins and cytoskeletal proteins that help set-up molecular asymmetries and hence establish polarity within a cell. See the Review on p. 799

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Dear students, postdocs and mentors,

We write to share our enthusiasm about the MBL Embryology course and to encourage graduate students and postdoctoral fellows to apply for the 2011 summer course “Embryology: Concepts and Techniques in Modern Developmental Biology” at the Marine Biological Laboratory from June 5 – July 17, 2011.  The application deadline has now been extended, and the MBL will accept applications up to Feb. 15th (although the website will continue to give a Feb 1 deadline).  Further course description and application information is available at

http://www.mbl.edu/education/courses/summer/course_embryo.html

This course provides a unique intensive laboratory-lecture experience in contemporary developmental biology.  Students receive instruction from leaders in the field and also have the opportunity to conduct a series of laboratory exercises/investigations using state-of-the-art equipment and a wide range of model and non-model developmental organisms.  We believe that the unique educational experience provided by the Embryology Course is not available at any home institution.  In our experience, students leave this course with an increased breadth of understanding together with practical and novel laboratory experiences and a greatly expanded network of scientific colleagues.

The curriculum is divided into three areas: 1) modern comparative embryology and molecular phylogeny, cell lineage and cell specification; 2) pattern and organ formation; and 3) transcriptional regulation and the analysis of gene networks and developmental pathways.  Students will be exposed to a broad variety of marine and terrestrial invertebrates and vertebrates, and the increasingly sophisticated methods employed to analyze their development. Daily lectures, extended discussions and frequent informal talks provide an intense intellectual experience where students and faculty alike are immersed in sophisticated and continuously changing conceptual and experimental explorations.

We assure you that funds are available to provide substantial financial assistance to defray the cost of tuition.  In 2010 the MBL was able to provide up to 75% of these costs from NIH funding to the course as well as from endowed scholarships.  We expect to provide similar financial aid in 2011.

From our experience as faculty in the course and now as the co-directors, it is our belief that sending a student to this course is a proven, sound investment for the scientific future of the student, lab, and the developmental biology community, and requires only a relatively short absence from the home institution.

If you have any questions please contact Lee, Nipam or Carol Hamel, Admissions Coordinator, at admissions@mbl.edu

Sincerely,

Nipam Patel

University of California, Berkeley

nipam@uclink.berkeley.edu

Lee Niswander

University of Colorado Denver

Lee.Niswander@ucdenver.edu

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