Editors' ChoiceEpigenetics

Establishing Memory of Gene Repression

Sci. Signal.  23 Sep 2014:
Vol. 7, Issue 344, pp. ec263
DOI: 10.1126/scisignal.2005925

Although cells in the body contain the same DNA content, they can display widely varying form and function among tissues. This occurs through differential gene regulation and by the establishment of a type of memory of gene expression that is transmitted to daughter cells during cell division. Gaydos et al. report that, in nematodes, both sperm and oocytes transmitted a memory of chromatin repression to embryos in the form of modified histones. During DNA replication, modified histones were passed to daughter chromatids to provide chromatin memory for a few cell divisions. Histone-modifying enzymes replenished histone modifications and provided long-term chromatin memory.

L. J. Gaydos, W. Wang, S. Strome, H3K27me and PRC2 transmit a memory of repression across generations and during development. Science 345, 1515–1518 (2014). [Abstract] [Full Text]