RING finger found in Drosophila melanogaster male-specific lethal-2 (MSL2) and similar proteins
MSL2, also known as RING finger protein 184 (RNF184), is a putative DNA-binding protein required for X chromosome dosage compensation in Drosophila males. Its expression is sex specifically regulated by Sex-lethal. Drosophila dosage compensation proteins MOF, MSL1, MSL2, and MSL3 are essential for elevating transcription of the single X chromosome in the male (X chromosome dosage compensation). MSL2 plays a critical role in translation and/or stability of MSL1 in males. In complex with MSL1, it acts as an E3 ubiquitin ligase that promotes ubiquitination of histone H2B. MSL2 contains a C3HC4-type RING-HC finger and a metallothionein-like domain with eight conserved and two non-conserved cysteines, as well as a positively and a negatively charged amino acid residue cluster and a coiled coil domain that may be involved in protein-protein interactions. This family also includes many male-specific lethal-2 homologs from bilaterians.