University of Southern California
Ray R. Irani Hall
Molecular and Computational Biology
Seminar Series
Meng Chen
Dept. of Biology
Duke University
“Phytochrome Nuclear Bodies and
Light Signaling in Plants”
Abstract:
Light plays a profound role in plant development, yet how photoreceptor excitation directs phenotypic plasticity remains elusive. One of the earliest effects of light is the regulated translocation of the red/far-red photoreceptors, phytochromes, from the cytoplasm to subnuclear foci called phytochrome nuclear bodies. The function of these nuclear bodies is unknown. We carried out a unique genetic screen looking for phyB:GFP mislocalization mutants. This screen identified a novel photomorphogenetic mutant, hemera (hmr). hemera mutants are impaired in all phytochrome responses examined, including proteolysis of phytochrome A and phytochrome-interacting transcription factors. We show that HEMERA has a function in the nucleus, where it acts specifically in phytochrome signaling, is predicted to be structurally similar to the multiubiquitin-binding protein, RAD23, and can partially rescue yeast rad23mutants. Together, these results implicate phytochrome nuclear bodies as sites of proteolysis.
Friday, April 9, 2010
12:00 pm
RRI 101
Host: Xuelin Wu
