SMAD family member 9 (SMAD9)

SMAD9 (SMAD family member 9) is a transcription factor in the BMP branch of the TGF-β signaling superfamily. It functions as a receptor-regulated SMAD (R-SMAD), activated by phosphorylation downstream of BMP type 1 receptor kinases. Once phosphorylated, SMAD9 dissociates from the membrane anchor SARA and forms complexes with SMAD4, which translocate to the nucleus and regulate gene expression. SMAD9 acts as a negative regulator of BMP signaling, fine-tuning cell differentiation and gene expression in development and disease. Evidence suggests unique repressive mechanisms and potential tumor suppressor activity in carcinoma, particularly lung cancer. It is most commonly referred to as SMAD9 in humans, though aliases like SMAD8 and MADH6 appear in literature.

Other names

SMAD9SMAD8MADH6MADH9Madh8SMAD8/9SMAD8ASMAD8BLOC103691556PPH2

Inhibition or activation of BMP signaling by altering SMAD9 phosphorylation or nuclear translocation; Modulation of transcriptional repression or activation of BMP target genes