Friends of the late Tracy M. Sonneborn established a lectureship in his memory in 1981. Support for this lecture has been provided by the Sonneborn Lecture Fund and the Department of Biology.
Tracy M. Sonneborn Lecture Series
Investigator and American Cancer Society Research Professor and Dean, The Graduate School of the Stowers Institute for Medical Research
Professor of Molecular and Integrative Physiology, School of Medicine, University of Kansas Medical Center
How a really really big structure facilitates meiosis
Thursday, February 22, 2018
4:00 p.m., Myers Hall 130
Abstract: Although many of the core aspects of the meiotic process are highly conserved, many of the proteins and structures that mediate meiosis are rapidly evolving. Two examples of that diversity are the proteins that comprise the central region of the synaptonemal complex (SC) and the Mtrm protein (a regulator of Polo kinase). Our discussion of the SC will focus both on the role of the very rapidly evolving transverse filament proteins C(3)G and Corolla in mediating assembly and structure as well as on a recently diverged family of E3 ligase proteins (Vilya, Narya, and Nenya), which mediate crossover formation. The consideration of the Mtrm protein will focus on the opportunity that specific mtrm mutant genotypes appear to play in allowing the transmission of newly arisen B chromosomes and, thus, in accelerating genome evolution. If a central theme can be crafted from the interweaving of these stories, it will be that meiosis (and many of the proteins that execute it) is surprisingly tolerant of genetic change, allowing the creation of new structural forms (the SC), novel means of executing critical processes like recombination (Vilya et al.), and even facilitating genome evolution. If time allows, balancers will be discussed.
About Tracy Sonneborn
Aside from a few years at Johns Hopkins University where he received the Ph.D. degree, Tracy Sonneborn spent his entire career at Indiana University. His devotion to the study of Paramecium established him as the world leader in biology and genetics of the Protozoa; indeed it is no exaggeration to say that he founded the modern era of study in these areas.
One of his major contributions was in demonstrating that preexisting structures in cells can repeatedly determine the patterns of new structures through many generations. Although recognized as an important exception to Mendelian inheritance and a critical element in prion diseases, the mechanism of structural inheritance in biology is not yet understood.
With precision, thoroughness, and infectious enthusiasm, Tracy Sonneborn also contributed unstintingly to teaching at Indiana University. In spite of the many attempts to entice him away, he remained loyal to IU, finding here the environment he thought was best. To honor his contributions to science and his outstanding career Tracy Sonneborn’s friends and colleagues initiated the Sonneborn Lectureship in 1981.
"Whatever the final outcome of studies of these phenomena, he must take his place among the most brilliant and devoted experimentalists in the history of biology and a true giant, like no other, in the field of protozoan research." John Preer