Molecular genetic dissection of anovel unilateral incompatibility within species, which observed in self-incompatible Brassica species

自交不亲和(SI)系统通过拒绝来自具有相同单倍型的植物的花粉来防止自交受精和促进异交。甘蓝型油菜的SI系统是由同一座位上的多个等位基因控制的，称为S基因座。在油菜属植物的花粉-柱头互作研究中，虽然存在种间识别系统，但种间识别分子尚不清楚。在对甘蓝型油菜进行单侧不亲和性遗传分析的过程中，我们观察到了一种新的单侧不亲和性，这种单侧不亲和性是以一个品种(OSome)为母本，土耳其系为花粉配对时所特有的。从遗传分析来看，该US基因座与S基因座是独立的。本研究的目的是对甘蓝型油菜中该基因进行分子克隆，从更深层次的遗传分析来看，花粉UI(PuI)表型受单隐性基因控制，柱头UI(SUI)表型受单显性基因控制。对于pui基因的分离，对F2分离群体进行了AFLP分析。结果共分离到6个连锁分子标记，分布在遗传图谱的18 cM范围内。通过比较遗传图谱和用户界面表型，进行了QTL分析。在分析中，PUI位于E-AAC/M-CCT和E-ACG/M-GAC标记之间(5 CM)。利用这些标记，我们将在不久的将来分离出PuI基因。

Self-incompatibility (SI) systems prevent self-fertilization and promote out-crossing by rejecting pollen from plants with the same Shaplotype. The Brassica SI system is controlled sporophytically by multiple alleles at the single locus, termed S locus. On the pollen-stigma interaction of Brassica species, although the recognition system between species should be existed, the recognition molecules between species are unknown. In the course of genetic analysis of SI in Brassica species, we observed a novel unilateral incompatibility (UI) in Brassica rapa L. This UI was specifically observed when one cultivar (Osome) was used a female partner, and Turkish lines were used as a pollen partner. From genetic analysis, this US locus was independent to S locus. This research purpose is molecular cloning of this UI gene in B. rapa.From more deep genetic analysis, pollen UI (PUI) phenotype was controlled by a single recessive gene, and stigma UI (SUI) phenotype was controlled by a single dominant gene. For isolation of PUI gene, AFLP analysis was performed with F2 segregation population. As a result, six linking molecular markers were isolated, and were scattered within 18cM on the genetic map. From the comparison of genetic map and UI phenotype, we performed QTL analysis. In the analysis, PUI was located between E-AAC/M-CCT and E-ACG/M-GAC markers (5cM). By using these markers, we will isolate the PUI gene, near future.