The function of BEX4 (brain expressed X-linked 4, Ensembl gene identifier ENSG00000102409) is as follows. May play a role in microtubule deacetylation by negatively regulating the SIRT2 deacetylase activity toward alpha-tubulin and thereby participate in the control of cell cycle progression and genomic stability (PubMed:27512957). In absence of reductive stress, acts as a pseudosubstrate for the CRL2(FEM1B) complex: associates with FEM1B via zinc, thereby preventing association between FEM1B and its substrates (By similarity). {ECO:0000250|UniProtKB:Q9CWT2, ECO:0000269|PubMed:27512957}.