Figure 5. Synaptonemal complex (SC) protein disassembly in sperm and oocyte meiosis. Immunolocalization of SC proteins is shown in green and DNA in red. (A) The SC central element protein, SYP-1, departs asymmetrically from chromosomes early in the transition from diplotene to diakinesis during spermatogenesis but retained on oocyte chromosomes until late diakinesis. (B) The axial/lateral element protein HIM-3 associates to chromosomes similarly in sperm and oocyte condensation zones. (C) AIR-2 is present along each chromosomal axis in pachytene and early diplotene nuclei in oogenesis and spermatogenesis. In oogenesis, AIR-2 is not detectable in late diplotene or early diakinesis but reappears in late diakinesis on the short arms of each bivalent. During spermatogenesis, AIR-2 localizes to discrete regions on karyosome then shifts in localization to the short arms of the bivalents during diakinesis. (D) AIR-2 is absent during pachytene in
syp-1(
me17) mutants in both oogenesis and spermatogenesis. AIR-2 reappears during spermatogenesis, but is mislocalized in an uneven distribution around univalents. AIR-2 during oogenesis reappears during diakinesis only in
syp-1(
me17) mutants mated with WT males in the -1 oocyte (unmated
syp-1(
me17) -1 oocyte is not shown) and is also mislocalized. Scale bars represent 2 um. Panels in rows corresponding to sperm or oocyte are sized the same as in (A).