Figure 4.

CEN-pairing in mouse spermatocytes. (A) Chromosome spreads of wild-type mouse spermatocytes in the diplotene stage of meiotic prophase (see Fig. 1) (image provided by R. Pezza). SYCP3 antibody was used to label axial elements. CREST antibody was used to label centromeres. SYCP1 antibody was used to demonstrate its presence at the paired centromeres and sites of chiasmata during this stage of meiosis. Blue arrowheads indicate examples of paired centromeres on chromosomes that have disassembled most synaptonemal complex proteins from the chromosome arms. (B) A cartoon of two homologous chromosomes engaged in centromere pairing (blue arrowhead). Light purple circles represent centromeres. Green lines represent the lateral elements. Persisting SC proteins are indicated in red.