Nucleosome-independent functions for the histone H3.3 variant in retroelement and gene repression
To fit two meters of DNA into a cell’s nucleus, DNA is wrapped around histone proteins to form the nucleosome, the basic unit of chromatin. Researchers have long known that variants to these histones exist in most eukaryotic organisms but the functions of these variants are not fully understood. Dominik Hoelper from the Lewis Lab spent his Ph.D. investigating a variant called H3.3. One of his findings is that surprisingly H3.3 has roles in the cell outside of the nucleosome. One of these functions is to stabilize one of its partner proteins called DAXX. Because several human cancers have mutations that inactivate DAXX, this stabilization is extremely important in the cell. Studying mouse embryonic stem cells, he elucidated the details of this stabilization and its relevance in a process by which DAXX keeps the expression of ancient viral sequences in our genome in check.
Learn more about his work at his Thesis Review at 2 p.m. on Tuesday, Dec. 11 in Room 1211 of the HFD Biochemical Sciences Building.