Transforming Growth Factor Alpha (TGFA) Active Protein

Transforming growth factors (TGFs) are biologically active polypeptides that reversibly confer the transformed phenotype on cultured cells. TGF-alpha shows about 40% sequence homology with epidermal growth factor (EGF; MIM 131530) and competes with EGF for binding to the EGF receptor (MIM 131550), stimulating its phosphorylation and producing a mitogenic response.[supplied by OMIM]

Function: TGF alpha is a mitogenic polypeptide that is able to bind to the EGF receptor and to act synergistically with TGF beta to promote anchorage-independent cell proliferation in soft agar.

Subunit structure: Interacts with the PDZ domains of MAGI3, SDCBP and SNTA1. The interaction with SDCBP, is required for the targeting to the cell surface. In the endoplasmic reticulum, in its immature form (i.e. with a prosegment and lacking full N-glycosylation), interacts with CNIH. In the Golgi apparatus, may form a complex with CNIH and GORASP2. Interacts (via cytoplasmic C-terminal domain) with NKD2. Ref.16 Ref.17 Ref.18

Subcellular location: Transforming growth factor alpha: Secreted › extracellular space. Protransforming growth factor alpha: Cell membrane; Single-pass type I membrane protein.

Tissue specificity: Isoform 1, isoform 3 and isoform 4 are expressed in keratinocytes and tumor-derived cell lines. Ref.6

Sequence similarities: Contains 1 EGF-like domain.