References
Activated TGFBR1/TGFBR2 complex attracts the TAB2/TAB3 proteins which promote activation of TAK1 (by phosphorylation).
TAB1 is an essential cofactor required for activation of TAK1 by upstream stimuli. Endogenous TAK1 is activated by TGF-beta IL-1 and TNF.
PMID:20060931 PMID:11274345