PhD position – Gut feeling: an exploration into how neural sensing of organ volume controls animal physiology and behaviour
Posted by Barry Denholm, on 5 November 2021
Closing Date: 16 December 2021
Many internal organs fill and empty periodically while carrying out their normal physiological function. Associated peripheral neurons act as specialised mechanoreceptors to detect changes in organ volume, and relay this information to the brain, where it is processed, and used to evoke appropriate physiological and behavioural response(s). For example, during a meal the stomach expands to accommodate ingested food, triggering neural circuits to inhibit feeding behaviour, promote digestion, and evoke feelings of satiety, fullness, nausea or pain, depending on the size of the meal. Despite being central to normal physiological function many basic questions remain about the mechanisms of organ volume sensing.
In this project you will explore how mechanisms of gut volume sensing control physiology and life cycle in a classic insect model—the blood-sucking bug Rhodnius prolixus. You will use state-of-the-art techniques in genomics, imaging, genetic manipulation, and gene/protein expression analysis to identify the molecular and cellular mechanisms of mechanotransduction in the Rhodnius gut and define the relevant neural circuits that act to control profound changes in this creature’s physiology and development in response to feeding.
This project is a curiosity-driven exploration into a fundamental question relating to how animals sense and respond to their internal world. The molecular mechanisms of organ volume sensing are not well understood for any animal, including humans, but are likely to be conserved. Therefore, the project is likely to provide insight into physiological processes that are key for maintaining health in humans, illuminating areas relating to appetite, overeating and disorders connected to visceral pain.
Specific details about the project: Rhodnius prolixus is a blood-sucking bug of immoderate feeding habits. It can take from its host a volume of blood sufficient to increase its own weight by about tenfold. The food-swollen gut distends the abdomen and sets in train a series of endocrinological processes that culminate in profound changes to the physiology and life cycle of the animal. These include (i) a rapid diuretic response, enabling the animal to jettison excess salts and water, returning the animal to a more comfortable state, and (ii) stimulation of body growth and maturation that precede the transition to the next life phase (an older nymph or metamorphosis to adult form).
A major goal of the current project is to determine how abdominal distension is sensed and transduced to the brain to elicit such dramatic changes.
For more details please contact: Barry.Denholm@ed.ac.uk
Application Procedure
Download application and reference forms from:
http://www.eastscotbiodtp.ac.uk/how-apply-0
Completed application form along with your supporting documents should be sent to our PGR student team at sbms-postgraduate@ed.ac.uk by 16 December 2021. References: Please send the reference request form to two referees. Completed references for this project should also be returned to sbms-postgraduate@ed.ac.uk by the closing date: 16 December 2021.
It is your responsibility to ensure that references are provided by the specified deadline.