Figure 7: Multiple cohesin complexes
tether meiotic chromosomes. (Top), A
schematic diagram of meiotic-specific cohesin
complexes and a mitotic cohesin complex.  These
cohesin complexes share two SMC proteins and
one non-SMC protein but differ in the non-SMC
subunit called kleisin.  Klesin subunit REC-8 and
the two nearly identical kleisin paralogs COH-3
and COH-4 are meiotic specific. SCC-1 mediates
sister chromatid cohesion during mitosis.
(Bottom), Confocal micrographs of paired and
synapsed homologous meiotic chromosomes
(pachytene chromosomes) show that REC-8 and
COH-3/4 are present all along the homologs and
co-localize with the axis protein HTP-3.