Genetic mapping of a locus controlling the intergeneric hybridization barrier between apple and pear
Genetic mapping of a locus controlling the intergeneric hybridization barrier between apple and pear
复制标题
控制苹果和梨属间杂交障碍的基因座的遗传图谱
DOI：
10.1007/s11295-019-1397-7
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发表时间：
2019
影响因子：
2.4
通讯作者：
Itai Akihiro
中科院分区：
文献类型：
--
作者：
Morimoto Takuya;Inaoka Maia;Banno Kiyoshi;Itai Akihiro
由于不亲和反应，涉及不同物种的杂交常常受到阻碍。虽然这些生殖障碍已在许多植物物种中观察到，但其潜在机制仍有待全面阐明。在这项研究中，我们检测了苹果（Malus×domestica）和梨（Pyrusspp.）之间的杂交障碍。属于蔷薇科海葵亚族的不同属。梨花粉与苹果雌蕊亲和性试验表明，梨花粉与苹果雌蕊亲和性较好，而欧洲梨花粉与苹果雌蕊不亲和。这些结果表明梨属物种间存在明显的互（不）亲和反应.基于梨属间花粉管行为的差异，通过基因组测序和精细分型技术，对苹果属与梨属间杂种的花粉管行为进行了分析，并对影响梨属间花粉管行为的基因组区域进行了定位。我们在5号染色体上定义了一个单一的位点，其中P.梨属衍生的等位基因从梨属种间杂种完全遗传到属间杂种。在该基因组区域的235个基因中，80个表现出特定的花粉表达模式，包括参与自交不亲和反应的基因。这些候选基因在此讨论其可能的功能与生殖隔离。
Hybridizations involving different species are often hindered because of incompatibility reactions. Although these reproductive barriers have been observed in many plant species, the underlying mechanisms remain to be comprehensively elucidated. In this study, we detected a hybridization barrier between apple (Malus×domestica) and pear (Pyrusspp.) belonging to different genera in the subtribe Malinae of the family Rosaceae. Pollination experiments revealed thatPyrus pyrifolia(Japanese pear) pollen is compatible withMaluspistils, whereasPyrus communis(European pear) pollen is not. These results imply there is a distinct cross-(in)compatibility reaction occurring inPyrusspecies. Based on the varying pollen tube behaviors amongPyrusspecies, genetic analysis was conducted to identify the genomic region responsible for the intergeneric barrier.Malus–Pyrusintergeneric hybrids were used to detect distorted segregation regions by combining genome sequencing and fine-scale genotyping data. We defined a single locus on chromosome 5, in whichP. pyrifolia-derived alleles were exclusively inherited to the intergeneric hybrids from thePyrusinterspecific hybrid. Of the 235 genes in this genomic region, 80 exhibited a specific pollen-expression pattern, including genes involved in self-incompatibility reactions. These candidate genes are herein discussed regarding their possible functions related to reproductive isolation.