The basic function of MKRN2 is mediating ubiquitin-conjugating enzyme (E2)-dependent ubiquitination. Makorin RING zinc finger-2 (MKRN2), overlaps and is antisense to the gene RAF1 in mammals. Northern blot analyses show that human MKRN2 and RAF1 are co-expressed in tissues and cell lines, raising the possibility of mRNA duplex formation. The encoded makorin-2 protein is likely a ribonucleoprotein of unknown function, but its conservation suggests an important cellular role.