PIP1/WDR84 (PAK1IP1) was identified as a p21-activated protein kinase (PAK) interacting protein that functions as a negative regulator of PAK activity and PAK signaling pathways. PIP1/WDR84 (PAK1IP1) contains 5 G beta-like WD repeats. The WD repeat is defined by four or more repeating units of a conserved core of approximately 40 amino acids ending with tryptophan-aspartic acid (WD). WD repeats may serve as sites of protein-protein interaction for adaptor proteins and facilitate multiprotein complex formation.
