Fine mapping of QTL qCTB10-2 that confers cold tolerance at the booting stage in rice
Fine mapping of QTL qCTB10-2 that confers cold tolerance at the booting stage in rice
复制标题
水稻孕穗期抗寒QTL qCTB10-2精细定位
DOI：
10.1007/s00122-017-2992-3
复制
发表时间：
2018-01-01
影响因子：
5.4
通讯作者：
Li, Zichao
中科院分区：
文献类型：
--
作者：
Li, Jilong;Pan, Yinghua;Li, Zichao
将控制水稻孕穗期耐冷性的QTL qCTB 10 - 2定位在一个132.5kb的区域内，包含17个候选基因，其中4个基因为冷诱导基因。孕穗期低温是限制水稻生产的主要非生物胁迫。虽然已经报道了一些水稻耐冷性的QTL，但在孕穗期有效的QTL的精细定位很少。本研究利用从耐冷品种昆明小白谷（KMXBG）与冷敏感品种十和田（Towada）杂交获得的BC 7 F2群体中选择的近等基因系ZL 31 -2，对孕穗期耐冷性进行了QTL定位。利用BC 7 F3和BC 7 F4群体，我们首次确认了qCTB 10 -2，并获得了该基因可以精细定位的信心。QTL qCTB 10 -2分别解释了这两个世代13.9%和15.9%的表型变异。使用从较大的BC 7 F4和BC 7 F5群体中筛选的纯合重组体，qCTB 10 -2被限定在标记RM 25121和MM 0568之间的132.5kb区域。17个推测的预测基因位于该区域，只有5个预测编码表达蛋白。这5个基因的表达模式表明，除了LOC_Os10g11820在低温胁迫下表达稳定外，与十和田相比，ZL 31 -2中的LOC_Os10g11730、LOC_Os10g11770和LOC_Os10g11810在低温胁迫下的表达受到高度诱导，而LOC_Os10g11750的表达差异不大。本研究结果为鉴定qCTB 10 -2基因奠定了基础，表明与qCTB 10 -2基因连锁的分子标记可用于水稻孕穗期耐冷性的分子辅助选择。
The QTL qCTB10 - 2 controlling cold tolerance at the booting stage in rice was delimited to a 132.5 kb region containing 17 candidate genes and 4 genes were cold-inducible. Low temperature at the booting stage is a major abiotic stress-limiting rice production. Although some QTL for cold tolerance in rice have been reported, fine mapping of those QTL effective at the booting stage is few. Here, the near-isogenic line ZL31-2, selected from a BC7F2population derived from a cross between cold-tolerant variety Kunmingxiaobaigu (KMXBG) and the cold-sensitive variety Towada, was used to map a QTL on chromosome 10 for cold tolerance at the booting stage. Using BC7F3and BC7F4populations, we firstly confirmed qCTB10-2 and gained confidence that it could be fine mapped. QTL qCTB10-2 explained 13.9 and 15.9% of the phenotypic variances in those two generations, respectively. Using homozygous recombinants screened from larger BC7F4and BC7F5populations, qCTB10-2 was delimited to a 132.5 kb region between markers RM25121 and MM0568. 17 putative predicted genes were located in the region and only 5 were predicted to encode expressed proteins. Expression patterns of these five genes demonstrated that, except for constant expression of LOC_Os10g11820, LOC_Os10g11730, LOC_Os10g11770, and LOC_Os10g11810 were highly induced by cold stress in ZL31-2 compared to Towada, while LOC_Os10g11750 showed little difference. Our results provide a basis for identifying the genes underlying qCTB10-2 and indicate that markers linked to the qCTB10-2 locus can be used to improve the cold tolerance of rice at the booting stage by marker-assisted selection.