Dr. Mark Estelle: University of California San Diego Section of Cell and Developmental Biology 

Title: Auxin transcriptional networks from beginning to end

Abstract: Auxin controls growth and diverse physiological processes through a complex gene regulatory network that includes thousands of genes. Auxin regulates gene expression by promoting the degradation of transcriptional repressors called Aux/IAA proteins. The Aux/IAAs repress transcription by interacting with AUXIN RESPONSE FACTOR (ARF) transcription factors and recruiting members of the TOPLESS (TPL) family of co-repressors to the chromatin. The 29 Aux/IAA genes in Arabidopsis exhibit unique but partially overlapping patterns of expression. Although some studies have suggested that individual Aux/IAA genes have specialized function, genetic analyses of the family have been limited by the lack of loss-of-function phenotypes, presumably because of overlapping function. Further, with a few exceptions, our knowledge of the factors that regulate Aux/IAA expression is limited. We have recently shown that several Aux/IAA proteins are required for drought tolerance in Arabidopsis. Surprisingly, the role of the Aux/IAAs in this instance appears to be to regulate glucosinolate biosynthesis.  

Refreshments will be served prior to the GDCB Seminar at 3:45 p.m.

Host: Dior Kelley