Human TGIF1 Antibody

TGIF1 (5'-TG[TCA]-3' Interacting Protein 1; also Transforming growth factor beta-induced factor and HPE4) is a 43 kDa (predicted) member of the TALE/TGIF homeobox family of proteins. It is widely expressed, and serves as a transcriptional corepressor for SMAD2-induced gene activation. Evidence suggests that it either complexes with c-jun and cPML, or interacts with HDAC in the nucleus to perform this function. It also binds to RXR response elements, blocking RXR-mediated gene activation. Such interactions are of considerable importance during fetal and neonatal development. Human TGIF1 is 401 amino acids (aa) in length. It contains a DNA-binding homeobox domain (aa 164-226) and two consecutive repressor domains (aa 267-401). There are multiple splice variants. One is very well characterized, is 33-35 kDa in size, and shows a four aa substitution for aa 1-133. This is most active when phosphorylated, which adds approximately 2-4 kDa to its SDS-PAGE MW. Two other splice forms contain a 19 aa substitution for aa 1-134, and utilize an alternative start site at Met150, respectively. Over aa 245-359, human TGIF1 shares 81% aa identity with mouse TGIF1.