The function of ALKBH4 (alkB homolog 4, lysine demethylase, ENSG00000160993) is as follows. Dioxygenase that mediates demethylation of actin monomethylated at 'Lys-84' (K84me1), thereby acting as a regulator of actomyosin-processes (PubMed:23673617). Demethylation of actin K84me1 is required for maintaining actomyosin dynamics supporting normal cleavage furrow ingression during cytokinesis and cell migration (PubMed:23673617). In addition to proteins, also demethylates DNA: specifically demethylates DNA methylated on the 6th position of adenine (N(6)-methyladenosine) DNA, thereby regulating Polycomb silencing (By similarity). {ECO:0000250|UniProtKB:Q9D8F1, ECO:0000269|PubMed:23673617}.