Self-incompatibility in the genus Arabidopsis:: Characterization of the S locus in the outcrossing A-lyrata and its autogamous relative A-thaliana
Self-incompatibility in the genus Arabidopsis:: Characterization of the S locus in the outcrossing A-lyrata and its autogamous relative A-thaliana
复制标题
DOI：
10.1105/tpc.13.3.627
复制
发表时间：
2001-03-01
期刊：
影响因子：
11.6
通讯作者：
Nasrallah, ME
中科院分区：
文献类型：
--
作者：
Kusaba, M;Dwyer, K;Nasrallah, ME
为了研究十字花科植物自交不亲和系统的系统发育，阐明十字花科植物异交系统和自交不亲和系统之间转换的遗传基础，我们研究了琴叶拟南芥（Arabidopsis lyrata）的自交不亲和系统。A. lyrata是自花可育A. thaliana，并被认为是从A. thaliana相似于500万年前，而Brassica spp相似于1500 - 2000万年前。Lyrata的S位点含有S位点受体激酶（SRK）基因和S位点富含半胱氨酸蛋白（SCR）基因的紧密连锁的直向同源物，这两个基因分别是柱头和花粉中SI特异性的决定因素，但缺少S位点糖蛋白基因。如之前在Brassica中所述，A.琴琴的不同之处在于它们基因的重排顺序和它们可变的身体大小。A. lyrata和芸苔属S基因座的比较表明，十字花科植物的S基因座是一个动态基因座，自拟南芥-芸苔属分裂以来经历了几次重复事件，并在两个分类群的多样化过程中作为一个单元在两个遥远的染色体位置之间易位。此外，对A. lyrata及其在自花可育A. thaliana鉴定了SRK和SCR基因的直系同源物，并证明该物种的自交亲和性与SI特异性基因的失活有关。
As a starting point for a phylogenetic study of self-incompatibility (SI) in crucifers and to elucidate the genetic basis of transitions between outcrossing and self-fertilizing mating systems in this family, we investigated the SI system of Arabidopsis lyrata. A. lyrata is an outcrossing close relative of the self-fertile A. thaliana and is thought to have diverged from A. thaliana similar to5 million years ago and from Brassica spp 15 to 20 million years ago, Analysis of two S (sterility) locus haplotypes demonstrates that the A. lyrata S locus contains tightly linked orthologs of the S locus receptor kinase (SRK) gene and the S locus cysteine-rich protein (SCR) gene, which are the determinants of SI specificity in stigma and pollen, respectively, but lacks an S locus glycoprotein gene. As described previously in Brassica, the S haplotypes of A. lyrata differ by the rearranged order of their genes and by their variable physical sizes. Comparative mapping of the A. lyrata and Brassica S loci indicates that the S locus of crucifers is a dynamic locus that has undergone several duplication events since the Arabidopsis-Brassica split and was translocated as a unit between two distant chromosomal locations during diversification of the two taxa. Furthermore, comparative analysis of the S locus region of A. lyrata and its homeolog in self-fertile A. thaliana identified orthologs of the SRK and SCR genes and demonstrated that self-compatibility in this species is associated with inactivation of SI specificity genes.