?

UBA-like domain found in FAS-associated factor 1 (FAF1) and similar proteins FAF1, also called UBX domain-containing protein 12 or UBX domain-containing protein 3A, is a multi-functional Fas associating protein that contains an N-terminal ubiquitin-associated (UBA)-like domain, UAS and ubiquitin-like (UBX) domains, p150 subunit of a chromatin assembly factor like domain (CAF) and a novel nuclear localization signal (NLS). FAF1 is an apoptotic signaling molecule that acts downstream in the Fas signal transduction pathway. It interacts with the cytoplasmic domain of Fas, but not to a Fas mutant that is deficient in signal transduction. FAF1 is widely expressed in adult and embryonic tissues, and in tumor cell lines, and is localized not only in the cytoplasm where it interacts with Fas, but also in the nucleus. FAF1 contains phosphorylation sites for protein kinase CK2 within the nuclear targeting domain. Phosphorylation influences nuclear localization of FAF1 but does not affect its potentiation of Fas-induced apoptosis. Other functions have also been attributed to FAF1. It inhibits nuclear factor-kappaB (NF-kappaB) by interfering with the nuclear translocation of the p65 subunit. Although the precise role of FAF1 in the ubiquitination pathway remains unclear, FAF1 interacts with valosin-containing protein (VCP) which is involved in the ubiquitin-proteosome pathway.
|