Abstract
Gametophytic self-incompatibility (GSI) is controlled by a complex S locus containing the pistil determinant S-RNase and pollen determinant SFB/SLF. Tight linkage of the pistil and pollen determinants is necessary to guarantee the self-incompatibility (SI) function. However, multiple probable pollen determinants of apple and Japanese pear, SFBBs (S locus F-box brothers), exist in each S haplotype, and how these multiple genes maintain the SI function remains unclear. It is shown here by high-resolution fluorescence in situ hybridization (FISH) that SFBB genes of the apple S 9 haplotype are physically linked to the S 9 -RNase gene, and the S locus is located in the subtelomeric region. FISH analyses also determined the relative order of SFBB genes and S-RNase in the S 9 haplotype, and showed that gene order differs between the S 9 and S 3 haplotypes. Furthermore, it is shown that the apple S locus is located in a knob-like large heterochromatin block where DNA is highly methylated. It is proposed that interhaplotypic heterogeneity and the heterochromatic nature of the S locus help to suppress recombination at the S locus in apple.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
