Sun Bin, Zhan Xiao-Deng, Lin Ze-Chuan, Wu Wei-Xun, Yu Ping, Zhang Ying-Xin, Sun Lian-Ping, Cao Li-Yong, Cheng Shi-Hua
Chinese National Center for Rice Improvement, China National Rice Research Institute, Hangzhou, 310006, China.
State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China.
Theor Appl Genet. 2017 Jan;130(1):247-258. doi: 10.1007/s00122-016-2787-y. Epub 2016 Sep 27.
A major QTL for heading date, qHD5, was fine-mapped to a 52.59-kb region on the short arm of rice chromosome 5. Heading date (HD) is one of the most important traits that enables rice to adapt to seasonal differences and specific growth conditions in diverse growing regions. In this study, a major-effect quantitative trait locus (QTL), qHD5, was resolved as a single Medelian factor that causes NIL(BG1) and NIL(XLJ) (two near-isogenic lines (NILs) used in our study) to have at a minimum of 10-day difference in HD under both long-day and short-day conditions in rice. qHD5 was initially mapped to a 309.52-kb genomic region in our previous study. Here, using an advanced BCF population and map-based cloning, we further narrowed the location of qHD5 to a 52.59-kb region between the H71 and RD502 markers. Sequence analysis revealed that Os05g03040, which putatively encodes an AP (APETALA2) transcription factor, has six single nucleotide polymorphisms (SNPs) between NIL(BG1) and NIL(XLJ). On this basis, this gene was concluded to be the most probable candidate gene for qHD5. Our results also showed that Hd3a, RFT1, Hd1, Ehd1, and Ghd7 were differentially expressed in the two NILs. Moreover, qHD5 was found to affect yield-related traits such as flag leaf width, flag leaf length, branch number, and 1000-grain weight.
一个控制抽穗期的主效QTL（qHD5）被精细定位到水稻第5号染色体短臂上一个52.59 kb的区域。抽穗期是使水稻能够适应不同种植区域季节性差异和特定生长条件的最重要性状之一。在本研究中，一个主效数量性状位点（QTL）qHD5被解析为一个单孟德尔因子，该因子使得NIL（BG1）和NIL（XLJ）（本研究中使用的两个近等基因系（NILs））在水稻的长日照和短日照条件下抽穗期至少有10天的差异。在我们之前的研究中，qHD5最初被定位到一个309.52 kb的基因组区域。在此，我们利用一个高级BCF群体和基于图谱的克隆技术，将qHD5的定位进一步缩小到H71和RD502标记之间的一个52.59 kb区域。序列分析表明，推定编码AP（APETALA2）转录因子的Os05g03040在NIL（BG1）和NIL（XLJ）之间有六个单核苷酸多态性（SNP）。在此基础上，该基因被认为是qHD5最有可能的候选基因。我们的结果还表明，Hd3a、RFT1、Hd1、Ehd1和Ghd7在这两个NILs中差异表达。此外，发现qHD5会影响与产量相关的性状，如剑叶宽度、剑叶长度、枝梗数和千粒重。
