The function of Ensembl gene identifier ENSG00000008256 (CYTH3, cytohesin 3) is as follows. Promotes guanine-nucleotide exchange on ARF1 and ARF6. Promotes the activation of ARF factors through replacement of GDP with GTP. Plays a role in the epithelial polarization (By similarity). {ECO:0000250|UniProtKB:O08967, ECO:0000269|PubMed:23940353, ECO:0000269|PubMed:9707577}.