The invention provides isolated nucleic acids molecules, designated 25501 nucleic acid molecules, which encode novel transferase family members. The invention also provides antisense nucleic acid molecules, recombinant expression vectors containing 25501 nucleic acid molecules, host cells into which the expression vectors have been introduced, and nonhuman transgenic animals in which a 25501 gene has been introduced or disrupted. The invention still further provides isolated 25501 proteins, fusion proteins, antigenic peptides and anti-25501 antibodies. Diagnostic and therapeutic methods utilizing compositions of the invention are also provided.