University of Pittsburgh Department of Biological Sciences Presents:
Dr. Lewis Held
Texas Tech University
"Hamlet on the Fly: To be or not to be a Foreleg?"
Monday, March 12, 2018
169 Crawford Hall
10:50 A.M. refreshments
Host: Dr. Burhan Gharaibeh
It is widely known that all eukaryotes share the same basic “machine code” of gene transcription, translation, intercellular signaling, and energy metabolism, but, until recently, it was widely assumed that different genes must be used by different phyla to build their bodies because their anatomies look so drastically different. Now that the genomes of so many animals from different phyla have been sequenced, we can compare gene circuits in great detail. Amazingly, it is beginning to dawn on us that the same “operating system” is used to set up the body axes, organ identities, and cellular differentiated states of virtually all bilaterally symmetric animals on Earth! Why? Because they all descended from an “Urbilaterian” ancestor who lived ~600 million years ago! That progenitor was anatomically more complex than anyone thought. In this talk, I compare humans and flies (members of two disparate phyla) RE their shared “tool kits” of circuits, which have been inherited from that ancestor. The talk is based on a new book (“Deep Homology?”) that describes all these circuits.