The invention provides an isolated gene encoding Mch6 as well as functional fragments thereof. Also provided are isolated nucleic acid sequences encoding Mch6 or functional fragments thereof. The gene or nucleic acid sequences can be single or double stranded nucleic acids corresponding to coding or non-coding strands of the Mch6 nucleotide sequences. The invention further provides an isolated Mch6 polypeptide and isolated large and small subunits of the Mch6 polypeptide, including functional fragments thereof.