- Broida 1640
Refreshments served at 3:40
Kenneth S. Kosik - University of California, Santa Barbara
After a brief introduction to the Neuroscience Research Institute at UCSB (http://www.nri.ucsb.edu/) and possible future collaborative research opportunities I will address the topic of brain evolution. In a recent issue of Nature, Philip Ball pointed out that the central dogma of biology---the linear flow of information from DNA to RNA to protein to phenotype---has been "sanitized to the point of distortion." Among the findings that have shaken biology is the surprisingly large fraction of the genome devoted, not to encoding proteins, but to complex regulatory circuits that control gene expression. How evolutionary novelty emerges necessarily engages every level of biology's hierarchical organization from molecular to cellular to organismal to social and, therefore, stands pari passu with every core issue of the field. In the animal kingdom, the relatively unchanged set of DNA sequences across phylogeny that encode proteins contrasts with the non-coding regulatory sequences that have expanded greatly as a function of organismal complexity. I will address one category of regulatory molecules, the microRNAs, which originate at evolutionary divergence points and, thereby, can mark speciation events. They also mark the acquisition of discrete cell identities and the emergence of a novel brain structure in the primate lineage.