RECESSIVE MUTATION MEI10 DISRUPTING MEIOS IS CYCLE IN RYE

The inheritance and manifestation of a spontaneous meiotic mutation wa s studied in rye. The mutation was characterized by supercompact chrom atin of meiotic chromosomes, a meiotic arrest at different stages, and disruption of a division spindle. As a result, fibrils did not conver ge at the poles. As the mutation was not expressed completely, some me iocytes went through both meiotic divisions. Cytokinesis did not occur in sporocytes, in which meiosis was blocked at different stages; howe ver, the sporocytes were covered with pollen wall, indicating that chr omosome reorganization, dynamics of microtubules, and formation of spo re cover occurred independently. Results of segregation in inbred prog eny and genetic analysis showed that the mutant phenotype was determin ed by the homozygous state of a recessive allele of a single gene. The gene was designated as mei10. It was shown that genes mei10 and sy10 (heterologous synapsis) were linked to each other with a recombination frequency between them of 25 +/- 2.8%. Both genes manifested independ ently in double recombinants.