Regulation of Smad activities.
TGF-beta (Transforming Growth Factor-beta) cytokines employ Smad proteins as the intracellular mediator of signaling. Upon TGF-beta stimulation, the cytoplasmic Smads become phosphorylated and consequently accumulate in the nucleus to regulate target gene expression. The cytoplasm-to-nucleus redistribution of Smads, as well as the ability of Smads to activate or repress gene transcription, is under multiple layers of regulation by factors not limited to TGF-beta. With recent advance in the knowledge of regulatory factors impinged on Smads, we are beginning to understand the complexity in cellular responses to TGF-beta.
Xu
Lan
L
Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street, Rm. 308, Worcester, MA 01605, USA. lan.xu@umassmed.edu
D000818:Animals; D001692:Biological Transport / Q000187:drug effects / Q000502:physiology; D002467:Cell Nucleus / Q000378:metabolism; D006801:Humans; D008954:Models, Biological; D010766:Phosphorylation / Q000187:drug effects; D051785:Smad Proteins / Q000378:metabolism*; D051896:Smad Proteins, Receptor-Regulated / Q000378:metabolism; D051901:Smad4 Protein / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000494:pharmacology / Q000502:physiology*
D051785:Smad Proteins; D051896:Smad Proteins, Receptor-Regulated; D051901:Smad4 Protein; D016212:Transforming Growth Factor beta