PARP-1 Flips the Epigenetic Switch on Obesity.

PARP enzymes are increasingly taking on important roles beyond DNA repair. Huang et al. (2020b) report how the NAD-dependent ADP-ribosylation of histone H2B by PARP-1 in complex with a metabolic enzyme suppresses the phosphorylation of an adjacent residue, impacting adipogenesis.

The Role of Mammalian Creb3-Like Transcription Factors in Response to Nutrients.

Our ability to overcome the challenges behind metabolic disorders will require a detailed understanding of the regulation of responses to nutrition. The Creb3 transcription factor family appears to have a unique regulatory role that links cellular secretory capacity with development, nutritional state, infection, and other stresses. This role in regulating individual secretory capacity genes could place this family of transcription factors at an important regulatory intersection mediating an animal's responses to nutrients and other environmental challenges.

Designing Cell-Type-Specific Genome-wide Experiments.

Multicellular organisms depend on cell-type-specific division of labor for survival. Specific cell types have their unique developmental program and respond differently to environmental challenges, yet are orchestrated by the same genetic blueprint. A key challenge in biology is thus to understand how genes are expressed in the right place, at the right time, and to the right level.

CAST-ChIP maps cell-type-specific chromatin states in the Drosophila central nervous system.

Chromatin organization and gene activity are responsive to developmental and environmental cues. Although many genes are transcribed throughout development and across cell types, much of gene regulation is highly cell-type specific. To readily track chromatin features at the resolution of cell types within complex tissues, we developed and validated chromatin affinity purification from specific cell types by chromatin immunoprecipitation (CAST-ChIP), a broadly applicable biochemical procedure.