Bivalent Polycomb Complexes as Master Switches of Developmental Gene Regulation

Abstract: The genomes of higher organisms are annotated by chromosomal proteins and histone modifications, which delineate active genes, regulatory elements, and silent regions. This annotation is critical for proper cell type specification, and an ongoing challenge is to decipher the rules that establish and maintain chromatin organization. Our studies of the highly conserved Polycomb group (PcG) epigenetic regulators in Drosophila has led my lab to propose a model in which the Polycomb Repressive Complex 1 (PRC1) and classical co-activators form ‘bivalent’ protein complexes on transcriptionally poised developmental genes. We speculate that these function as ‘master switches’ that are responsive to the amount of local acetylation or deacetylation activities recruited by cell type specific DNA binding factors, leading to stable but reversible activation or repression, respectively. Our model is based on chromatin crosslinking, affinity purification, and mass spectrometry experiments, in which Drosophila PRC1 strongly interacts with classical co-activators, dBRD4 and dMOZ. We are currently exploring potential parallels in mammalian development

cell biologygeneticsmolecular biology

Audience: researchers in the discipline

( video )

Comments: Organizers can be contacted at m.tariq@lums.edu.pk or 22100032@lums.edu.pk for the zoom link.

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Colloquium zooming Molecular & Cellular Biology LUMS

Series comments: Zooming Molecular & Cellular Biology Colloquium was initiated on July 28th, 2020 by the Biology department at Syed Babar Ali School of Science & Engineering (SBASSE), Lahore University of Management Sciences (LUMS). The series follows through various topics which come under the ambit of Molecular and Cellular Biology and we’ve had the pleasure and honor of hosting some of the most knowledgeable scientists from around the globe. Organizers can be reached out at 24100162@lums.edu.pk or 24100001@lums.edu.pk for the Zoom link of individual talks. All lectures are LIVE streamed on SBASSE's official Facebook page.

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