Sterol-regulatory element-binding protein (SREBP)-2 contributes to polygenic hypercholesterolaemia.

Sterol-regulatory element-binding protein (SREBP)-2 is a key regulator of cholesterol. When cells are deprived of cholesterol, proteolytic cleavage releases the NH(2)-terminal domain of SREBP-2 that binds and activates the promoters of SREBP-2-regulated genes including the genes encoding the low-density lipoprotein (LDL) receptor, 3-hydroxymethyl-3-glutaryl-(HMG-)CoA-synthase, and HMG-CoA-reductase. Thus, SREPB-2 gene activation leads to enhanced cholesterol uptake and biosynthesis.

Leaf-to-shoot apex movement of symplastic tracer is restricted coincident with flowering in Arabidopsis.

Classical experiments in plant physiology showed that leaves are the source of signals that control the development of flowers from shoot meristems. Additional physiological and genetic experiments have indicated some of the molecules (e.g.