NEDD4-like E3 ubiquitin-protein ligase WWP2 also known as atrophin-1-interacting protein 2 (AIP2) or WW domain-containing protein 2 (WWP2) is an enzyme that in humans is encoded by the WWP2 gene.

This gene encodes a member of the NEDD4-like protein family. The family of proteins is known to possess ubiquitin-protein ligase activity. The encoded protein contains 4 tandem WW domains. The WW domain is a protein motif consisting of 35 to 40 amino acids and is characterized by 4 conserved aromatic residues. The WW domain may mediate specific protein-protein interactions. Three alternatively spliced transcript variants encoding distinct isoforms have been found for this gene. [provided by RefSeq, Jul 2008].
Function: E3 ubiquitin-protein ligase which accepts ubiquitin from an E2 ubiquitin-conjugating enzyme in the form of a thioester and then directly transfers the ubiquitin to targeted substrates. Polyubiquitinates POU5F1 by 'Lys-63'-linked conjugation and promotes it to proteasomal degradation; in embryonic stem cells (ESCs) the ubiquitination is proposed to regulate POU5F1 protein level. Ubiquitinates EGR2 and promotes it to proteasomal degradation; in T-cells the ubiquitination inhibits activation-induced cell death. Ubiquitinates SLC11A2; the ubiquitination is enhanced by presence of NDFIP1 and NDFIP2. Ubiquitinates RPB1 and promotes it to proteasomal degradation.