This gene encodes a protein containing two characteristic WXXF motifs. The encoded protein localizes to clathrin-coated vesicles, where it binds components of the adapter protein complexes and aids in endocytosis. Loss of function of this gene results in early infantile epileptic encephalopathy-21. There is a pseudogene for this gene on chromosome 7. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jun 2014].