Cytomixis in tobacco microsporogenesis: are there any genome parts predisposed to migration?

Cytomixis is a poorly studied process of nuclear migration between plant cells, discovered in microsporogenesis of several hundreds of plant species. The chromosomes that migrate between tobacco microsporocytes have been for the first time identified using fluorescence in situ hybridization (FISH), and the question whether cytomixis is a random or a targeted process is answered. The distribution of four repetitive sequences used for identifying the tobacco chromosomes-NTRS, 5S rDNA, GRS, and HSR60-has been examined in the migrating chromatin, and the micronuclei formed after cytomixis. The distribution of tobacco S and T genomes has been analyzed in the cytomictic chromatin using genomic in situ hybridization (GISH). As has been shown (χ