HECT Domain And RCC1 Like Domain Protein 4 (HERC4)

HERC4 belongs to the HERC family of ubiquitin ligases, all of which contain a HECT domain and at least 1 RCC1-like domain (RLD). The 350-amino acid HECT domain is predicted to catalyze the formation of a thioester with ubiquitin before transferring it to a substrate, and the RLD is predicted to act as a guanine nucleotide exchange factor for small G proteins.The deduced 1,057-amino acid protein has an N-terminal RLD and a C-terminal HECT domain. Alternative splicing generates transcripts encoding proteins with altered or missing RLDs and HECT domains. RT-PCR detected prominent HERC4 expression in fetal brain and intermediate expression in adult brain and testis. Confocal immunofluorescence microscopy of transiently transfected HeLa cells showed HERC4 in a punctate cytoplasmic distribution.