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Context:

Lazar and his colleagues, including Cell and Molecular Biology graduate student Dan Feng, found a team of molecules that, in normal mice, migrates to the genome of liver cells during the daytime. One of the team members, a protein called Rev-erb, delivers the molecular workers to thousands of specific locations in the liver genome, many of which are near genes involved in the production of fat. Another team member, called histone deacetylase 3 (HDAC3), does construction work on the protein scaffold (the epigenome) surrounding the genome to dampen the activity of the fat-related genes.