CByJ.CBy-Map7^mshi/J

Stock number: 002169
Research areas: Reproductive Biology Research

Description

Mice homozygous for the male sterility and histoincompatibility spontaneous mutation (Map7^mshi) are characterized by reduced testis size and sterility. The testes are highly disorganized and appear to have a block in the regulation of male germ cell proliferation. In addition to the male reproductive defects this mutation also affects histocompatibility in both sexes. Most homozygous mutant mice reject sex-matched skin grafts from BALB/cBy mice.

Detailed description

Mice homozygous for the male sterility and histoincompatibility spontaneous mutation (Map7^mshi) are characterized by reduced testis size and sterility. The testes are highly disorganized and appear to have a block in the regulation of male germ cell proliferation. Reproduction is normal in homozygous mutant female mice. In addition to the male reproductive defects this mutation also affects histocompatibility in both sexes. Most homozygous mutant mice reject sex-matched skin grafts from BALB/cBy mice.

Development

The male sterility and histoincompatibility mutation (mshi) arose spontaneously at The Jackson Laboratory in a colony of BALB/cBy that was being used to assess cryopreservation-induced mutation rates by detecting skin-graft rejections. The mshi mutation was identified as a mutant subline that rejected BALB/cBy tail grafts. This mutant subline was maintained for four years by phenotyping for skin-graft rejection. After 7 backcrosses to BALB/cByJ this strain was maintained by sibling intercrossing progeny tested heterozygotes and in 2013 reached generation N7F38.

Allele

Symbol: Map7^mshi
Name: male sterility and histoincompatibility
MGI accession ID: MGI:1889849
Generation method: Spontaneous
Marker symbol: Map7
Marker name: microtubule-associated protein 7
Chromosome: 10
Strain of origin: BALB/cBy
Molecular note: A large 13,080 bp deletion begins at nucleotide 1616 in intron 10 and extends to nucleotide 1959 in the 3' downstream sequence beyond exon 18. Exon 10 is then spliced to a cryptic "exon 11M" 4213 bp downstream of the deletion breakpoint. Exon 11M is, in turn, spliced to a second cryptic "exon 12M" located 830 bp downstream of exon 11M. The resulting 1724 nucleotide transcript is predicted to code for a 457 amino acid mutant protein.