12:00 - 12:30 - Walk-in with Pizza
12:30 - 12:50 PhD Candidate (tbc)
Title:
Abstract:
12:50 -13:45 - Professor (Associate) Michael Poirier
Title: Revealing the mechanisms of linker histone mediate chromatin compaction with single-molecule fluorescence, force, and free energy studies
Abstract: The physical organization of eukaryotic genomes is evolutionarily conserved, where histone protein octamers repeatedly wrap genomic DNA into nanometer-size nucleosome spools to form chromatin: the basic organization structure of all eukaryotic genomes. Linker histones are ubiquitous chromatin organization proteins that control the physical accessibility of the genome to transcription regulatory factors. However, the mechanisms by which linker histones function to regulate genome accessibility at specific regions remain largely unknown. Single-molecule methods have proven to be a powerful method for investigating the regulation of chromatin dynamics and function. In this talk, I will first present recent single-molecule studies that use simultaneous force and fluorescence measurements to directly observe the mechanisms of how linker histones load onto chromatin. I will then present a new approach, Free Energy Spectroscopy (FES), that is based on DNA nanotechnology and transmission electron microscopy. This new method allows us to map out multidimensional free energy landscapes of chromatin compaction and learn how linker histones modify the chromatin conformational landscape to regulate genome accessibility. Finally, I will speculate on how FES is positioned to help answer a broad range of mechanistic questions about genome and epigenome function in the test tube and even in live cells.