POSH, or SH3 domain containing ring finger 1, is a human gene encoded by SH3RF1. It may also be known as: E3 ubiquitin-protein ligase SH3RF1; Protein POSH; RING finger protein 142; SH3 domain-containing RING finger protein 1; SH3 multiple domains protein 2; E3 ubiquitin-protein ligase SH3RF1 ; Plenty of SH3s; plenty of SH3 domains; RNF142; SH3MD2. The encoded protein is an enzyme with an amino acid length of 888 and a mass of 93.1 kDa. Other isoforms may exist. POSH is a member of the SH3RF family. Homologs of this gene exist in other organisms, including: Mouse, Rat, Frog.