Human Fas-Associated Factor 1, Interacting with Ubiquitinated Proteins and Valosin-Containing Protein, Is Involved in the Ubiquitin-Proteasom Pathway

다국어 초록 (Multilingual Abstract)

Human Fas-associated factor 1 (hFAF1) is a novel protein having multiubiquitin-related domains. We investigated the cellular functions of hFAF1 and found that valosin-containing protein (VCP) the multiubiquitin chain-targeting factor in the deradation of the ubiquitin-proteasome pathway is a binding partner of hFAF1.hFAF1 is associated with the ubiquitinated proteins via the newly identified N-terminal UBA domain and with VCP via the C-terminal UBX domain The overexpression of hFAF1 and a truncated UBAdomain inhibited the degradation of ubiquitinated proteins and increased cell death These results suggest that hFAF1 binding to ubiquitinated protein and VCP is involved in the ubiquitin-proteasome pathway We hypothesize that hFAF1 may serve as a scaffolding protein that regulates protein degradation in the ubiquitin-proteasome nathway.