The function of Ensembl gene identifier ENSG00000136051 (WASHC4, WASH complex subunit 4) is as follows. Acts as a component of the WASH core complex that functions as a nucleation-promoting factor (NPF) at the surface of endosomes, where it recruits and activates the Arp2/3 complex to induce actin polymerization, playing a key role in the fission of tubules that serve as transport intermediates during endosome sorting. {ECO:0000269|PubMed:19922875, ECO:0000269|PubMed:20498093, ECO:0000303|PubMed:21498477}.