The condensin complexes play distinct roles to ensure normal chromosome morphogenesis during meiotic division in A rabidopsis

Summary Meiosis is a specialized cell division essential for sexual reproduction. During meiosis the chromosomes are highly organized, and correct chromosome architecture is required for faithful segregation of chromosomes at anaphase I and II . Condensin is involved in chromosome organization during meiotic and mitotic cell divisions. Three condensin subunits, A t SMC 4 and the condensin I and II specific subunits A t CAP ‐ D 2 and A t CAP ‐ D 3, respectively, have been studied for their role in meiosis. This has revealed that both the condensin I and condensin II complexes are required to maintain normal structural integrity of the meiotic chromosomes during the two nuclear divisions. Their roles appear functionally distinct in that condensin I is required to maintain normal compaction of the centromeric repeats and 45 S r DNA , whereas loss of condensin II was associated with extensive interchromosome connections at metaphase I . Depletion of condensin is also associated with a slight reduction in crossover formation, suggesting a role during meiotic prophase I .