MRC Laboratory of Molecular Biology, Cambridge
Sex Circuits and Brain Maps
Monday 30 June 2014
Location: Large Lecture Theatre, Department of Physiology, Anatomy & Genetics, Sherrington Building
Abstract: Differences in behaviour between male and female animals provide a powerful model to understand the genetic and neural circuit basis of behaviour. Sex pheromones that trigger different behaviours in male and female animals have been identified in animals from worms to elephants.
In a few well-studied cases including mice and flies, the pheromone is known to bind and activate a specific odorant receptor in both sexes. If the pheromone activates sensory neurons in both sexes, why should the animals behave differently? It is likely that there are differences in neural circuits deeper in the brain.
I will present work from my group that describes, for the first time in any animal, a bidirectional neural circuit switch; this reroutes pheromone information to one set of target neurons in female brains and a different group in males. In addition to establishing the circuit basis of this switch, we have also uncovered some of the developmental genetic logic that determines its male or female state.
The functional studies that I have just mentioned began from fine scale mapping of olfactory circuits in the fly brain. I will also present briefly new genetic technology that we have developed for rapid labelling of neurons, along with computational tools to map neurons in the brain, measure the similarity between different neurons and to use this information to search and organise a database of more than 15,000 neurons. These approaches developed in the fly, may be portable to other systems including fish or mice.
Biography: Greg Jefferis received his undergraduate degree in Natural Sciences at Cambridge, followed by a PhD in Neurosciences at Stanford. His thesis work with Liqun Luo on the developmental logic of wiring specificity in the Drosophila olfactory system was awarded several prizes including a Harold Weintraub Graduate Student Award and the Elkins Memorial Lecture.
In 2004 he returned to Cambridge as a Wellcome Trust Advanced Training Fellow in the Department of Zoology and Research Fellow of St John’s College. During this fellowship period, he developed and applied new circuit mapping techniques and acquired skills in Drosophila electrophysiology. In 2008 he became a group leader in the Neurobiology Division of the MRC Laboratory of Molecular Biology. His work is supported by the MRC and an ERC Staring Investigator Grant; since 2012 he is an EMBO Young Investigator. His group studies the circuit basis of olfactory processing and behaviour, combining approaches including molecular genetics, imaging, computational neuroanatomy, in vivo electrophysiology and behavioural analysis.