TITLE: “Is there a Quiescence Histone Code?”
ABSTRACT: Many of the cells in our bodies are quiescent, that is, temporarily not dividing. Under certain physiological conditions such as during tissue repair and maintenance, quiescent cells receive the appropriate stimulus and are induced to enter the cell cycle. The ability of cells to successfully transition into and out of a quiescent state is crucial for many biological processes including wound healing, stem cell maintenance, and immunological responses. Histone modifications have been shown to play a role in chromatin packing and accessibility, nucleosome mobility, gene expression, and chromosome arrangement. We have been testing the role of the H4K20me3 mark as a regulator of quiescence in cultured cells and in mice. Our data implicate this histone mark in chromatin compaction, cell proliferation, chromosome positioning, expression of critical cell cycle regulatory proteins, and mouse growth during development. Moving forward, our goal is to test whether H4K20me3 is part of a histone code that ensures proper chromosome compaction and positioning to establish and maintain a quiescent state.
