The gunmetal mutation arose spontaneously in a C57BL/6J colony at The Jackson Laboratory in 1962 and was maintained by sibling intercrossing. Embryos were cryopreserved in 1980 using C57BL/6J females bred with homozygous males at generation F53. A cryorecovery of some of these embryos (stock #000110) was done for Dr. Luanne Peters to generate this strain.
|Gene Symbol and Name||Rabggta, Rab geranylgeranyl transferase, a subunit|
|Strain of Origin||C57BL/6J|
|Molecular Note||Mice carrying the gunmetal mutation have a G-to-A substitution in the splice site acceptor site at the 3' end of intron 1. It eliminates the exon 2 splice acceptor by changing it from CAG to CAA, leading to mis-splicing. RT-PCR of extracts from gunmetal mice yielded two transcripts, a dominant 429 base pair transcript that lacks exon 1 and is predicted not to encode functional protein, and the 638 base pair, intron alpha retaining transcript found in wildtype mice. RABGGTA protein and enzymatic activity are found in gunmetal mice, but both are reduced by 70% relative to wildtype siblings.|