Natural variation in a calreticulin gene causes reduced resistance to Ca2 deficiency-induced tipburn in Chinese cabbage (Brassica rapa ssp. pekinensis)
Natural variation in a calreticulin gene causes reduced resistance to Ca2 deficiency-induced tipburn in Chinese cabbage (Brassica rapa ssp. pekinensis)
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钙网蛋白基因的自然变异导致大白菜（Brassica rapa ssp. pekinensis）对 Ca2 缺乏引起的尖烧的抵抗力降低
DOI：
10.1111/pce.13612
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发表时间：
2019
期刊：
影响因子：
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通讯作者：
Fenglan Zhang
中科院分区：
文献类型：
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作者：
Tongbing Su;Peirong Li;Huiping Wang;Weihong Wang;Xiuyun Zhao;Yangjun Yu;Deshuang Zhang;Shuancang Yu;Fenglan Zhang
大菜烧心是大白菜上一种不可逆的生理病害，严重影响了大白菜的产量。由于强烈的环境因素，抗尖烧品种是唯一的解决方案，尽管大白菜中的抗尖烧基因是未知的。在田间条件下，我们研究了三个群体的大白菜在四个生长季节：（a）194个不同的自交系，（B）一个双单倍体（DH 100）群体，（c）F2群体。使用单核苷酸多态性标记对194个品系进行基因分型，全基因组关联图谱显示24个gQTL与烧尖病指数显著相关。对DH 100和F2群体的分析发现了一个共同的烧尖相关位点gqbTRA06，该位点覆盖了24个gQTL之一所定义的区域。在0.14 Mb数量性状基因座区域预测的35个基因中，Bra018575（钙网蛋白家族蛋白，BrCRT 2）在疾病发展过程中表现出较高的表达水平。我们克隆了两个BrCRT2等位基因，分别来自抗烧尖（BrCRT2R）和烧尖敏感（BrCRT2S）品系，并鉴定了BrCRT2S中的51 bp缺失。BrCRT2R的过表达增加了拟南芥t2突变体中的Ca2+储存，并且在Ca2+耗尽的条件下也减少了叶尖和叶缘的细胞死亡。这些结果表明BrCRT 2可能是控制大白菜尖烧病的候选基因。
Tipburn is an irreversible physiological disorder of Chinese cabbage that decreases crop value. Because of a strong environmental component, tipburn‐resistant cultivars are the only solution, although tipburn resistance genes are unknown in Chinese cabbage. We studied three populations of Chinese cabbage over four growing seasons under field conditions: (a) 194 diverse inbred lines, (b) a doubled haploid (DH100) population, and (c) an F2population. The 194 lines were genotyped using single nucleotide polymorphism markers, and genome‐wide‐association mapping showed that 24gQTLswere significantly associated with tipburn disease index. Analysis of the DH100 and F2populations identified a shared tipburn‐associated locus,gqbTRA06, that was found to cover the region defined by one of the 24gQTLs. Of 35 genes predicted in the 0.14‐Mb quantitative trait locus region,Bra018575(calreticulin family protein, BrCRT2) showed higher expression levels during disease development. We cloned the twoBrCRT2alleles from tipburn‐resistant (BrCRT2R) and tipburn‐susceptible (BrCRT2S) lines and identified a 51‐bp deletion inBrCRT2S. Overexpression ofBrCRT2Rincreased Ca2+storage in the Arabidopsiscrt2mutant and also reduced cell death in leaf tips and margins under Ca2+‐depleted conditions. Our results suggest thatBrCRT2is a possible candidate gene for controlling tipburn in Chinese cabbage.