A conserved SREBP-1/phosphatidylcholine feedback circuit regulates lipogenesis in metazoans.

Sterol regulatory element-binding proteins (SREBPs) activate genes involved in the synthesis and trafficking of cholesterol and other lipids and are critical for maintaining lipid homeostasis. Aberrant SREBP activity, however, can contribute to obesity, fatty liver disease, and insulin resistance, hallmarks of metabolic syndrome. Our studies identify a conserved regulatory circuit in which SREBP-1 controls genes in the one-carbon cycle, which produces the methyl donor S-adenosylmethionine (SAMe).

Mutator phenotype of Caenorhabditis elegans DNA damage checkpoint mutants.

DNA damage response proteins identify sites of DNA damage and signal to downstream effectors that orchestrate either apoptosis or arrest of the cell cycle and DNA repair. The C. elegans DNA damage response mutants mrt-2, hus-1, and clk-2(mn159) displayed 8- to 15-fold increases in the frequency of spontaneous mutation in their germlines.