[Polymorphism among RFL-PPR homologs in sunflower (Helianthus annuus L.) lines with varying ability for the suppression of the cytoplasmic male sterility phenotype].

A complex comparative genetic approach was used for the investigation of the structural and functional diversity of genes for the restoration of sunflower pollen fertility. It includes (i) hybridological analysis; (ii) analysis of polymorphism among EST fragments.homologous to the known Rf genes that contain repeated motives of 35 amino acids (RFL-PPR); (iii) the development of molecular markers. Monogenic segregation in three interline cross combinations and the results of molecular marker analysis confirmed the allelic differences of parental lines in the Mendelian locus for CMS PET1 pollen fertility restoration. Introns were found in two RFL-PPR fragments. Two allelic variants of the QHL12D20 fragment were detected among the sixty lines of the sunflower genetic collection. An intron of QHL12D20 fragment was homologous to an intron of the AHBP-1B gene; the product of this gene-has a similarity with the transcription factor of the bZIP-family of Arabidopsis. A relationship between the QHL12D20 polymorphism and the functional state of the Rfl locus was revealed.