Function
SMAD7 inhibits TGF-β signaling by preventing formation of Smad2/Smad4 complexes which initiate the TGF-β signaling. It interacts with activated TGF-β type I receptor therefore block the association, phosphorylation and activation of Smad2. By occupying type I receptors for Activin and bone morphogenetic protein (BMP), it also plays a role in negative feedback of these pathways.
Upon TGF- β treatment, Smad7 binds to discrete regions of Pellino-1 via distinct regions of the Smad MH2 domains. The interaction block formation of the IRAK1-mediated IL-1R/TLR signaling complex therefore abrogates NF-κB activity, which subsequently causes reduced expression of pro-inflammatory genes.
While Smad7 is induced by TGF-β, it is also induced by other stimuli, such as epidermal growth factor (EGF), interferon-γ and tumor necrosis factor (TNF)-α. Therefore it provides a cross-talk between TGF-β signaling and other cellular signaling pathways.
Read more about this topic: Mothers Against Decapentaplegic Homolog 7
Famous quotes containing the word function:
“The information links are like nerves that pervade and help to animate the human organism. The sensors and monitors are analogous to the human senses that put us in touch with the world. Data bases correspond to memory; the information processors perform the function of human reasoning and comprehension. Once the postmodern infrastructure is reasonably integrated, it will greatly exceed human intelligence in reach, acuity, capacity, and precision.”
—Albert Borgman, U.S. educator, author. Crossing the Postmodern Divide, ch. 4, University of Chicago Press (1992)
“The mother’s and father’s attitudes toward the child correspond to the child’s own needs.... Mother has the function of making him secure in life, father has the function of teaching him, guiding him to cope with those problems with which the particular society the child has been born into confronts him.”
—Erich Fromm (1900–1980)
“The function of the actor is to make the audience imagine for the moment that real things are happening to real people.”
—George Bernard Shaw (1856–1950)