Phenotype Image Detail

Image

Caption

Homologous synapsis, DNA double strand break (DSB) repair, homologous recombination, and telomere tethering to the linker of nucleoskeleton and cytoskeleton (LINC) complex are impaired in Spdya^tm1.1Klad/Spdya^tm1.1Klad spermatocytes. (A) In wild-type (WT, Spdya+/+) pachytene spermatocytes, SYCP3 and SYCP1 overlapped on autosomal chromosomes (arrow). SYCP1 was absent from unsynapsed regions of the XY body (arrowhead). (B) In mutant zygotene-like spermatocytes, SYCP1 was partially formed (arrowhead), indicating impaired synapsis. (C) In WT pachytene spermatocytes, gammaH2AX was restricted to the XY body as an indication that DNA DSB repair had been completed on autosomal chromosomes (arrow). (D) In mutant zygotene-like spermatocytes, gammaH2AX was observed along all chromosome axes (arrowheads). (E) In WT pachytene spermatocytes, the chiasmata marker MLH1 was observed at sites of recombination (arrow). (F) In mutant zygotene-like spermatocytes, MLH1 was absent from chromosomes (arrowhead), indicating that homologous recombination did not occur in mutant spermatocytes. (G-L) In WT pachytene spermatocytes, TERB1, MAJIN, and SUN1 are localized to telomeres on the NE (G, I, and K, arrows). In mutant zygotene-like spermatocytes, TERB1 and MAJIN are localized to telomeres on the NE (H and J, arrows), but SUN1 is observed along the NE as a polarized cap (L, arrow).

Copyright

This image is from Tu Z, Proc Natl Acad Sci U S A 2017 Jan 17;114(3):592-597. Copyright 2017 National Academy of Sciences, U.S.A. J:239544

Associated Alleles

Symbol	Name
Spdya^tm1.1Klad	speedy/RINGO cell cycle regulator family, member A; targeted mutation 1.1, Phillip Kladis

Associated Genotypes

Allelic Composition	Genetic Background
Spdya^tm1.1Klad/Spdya^tm1.1Klad	involves: 129S1/Sv * C57BL/6J