Shaping meiotic prophase chromosomes: cohesins and synaptonemal complex proteins

Recent progress in elucidating the function of synaptonemal complex (SC) proteins and of cohesins in meiocytes made possible, in particular, through the analysis of mice deficient in SC or cohesin proteins has significantly enriched our understanding of how meiotic chromosome architecture is determined. Cohesins and the SC proteins act together in generating the characteristic axis-loop structure of meiotic chromosomes, their pairing into bivalents, their ability to recombine, and to be properly segregated. This minireview attempts to summarize the current knowledge with a focus on higher eukaryotic systems and to ask questions that ought to be addressed in the future.