Beijing Key Laboratory of Molecular Genetics in Hybrid Wheat, Institute of Hybrid Wheat Beijing Academy of Agriculture and Forestry Sciences, Beijing, 100097, China.
College of Agronomy, Northwest A&F University, Yangling, 712100, Shaanxi, China.
Theor Appl Genet. 2023 Nov 28;136(12):257. doi: 10.1007/s00122-023-04500-0.
QMS-5B, a major QTL for photo-thermo-sensitive genic male sterility in wheat, was fine mapped in a 2.15 Mb region harboring a serine/threonine protein kinase gene TraesCS5B03G0887500, which was the most likely candidate gene. Genic male sterility is an essential trait in the utilization of heterosis and hybrid seed production for wheat. Currently, genic male sterile genes have been reported in wheat mutants, but the sterile genes controlling photo-thermo-sensitive genic male sterility in wheat have not been studied systematically. Here, 235 doubled haploid lines derived from a cross between photo-thermo-sensitive genic male sterile line BS462 and its restorer line CP279 were used to map male sterile gene by GenoBaits® Wheat 100 K Panel, bulked segregant exome sequencing (BSE-Seq) and wheat 660 K array. As a result, the major stable QTL on chromosome 5B, QMS-5B, was identified in all four environments, accounting for 7.3-36.4% of the phenotypic variances. Ulteriorly, QMS-5B was delimited to an approximate 2.15 Mb physical interval between KASP-5B5 and KASP-5B6 using kompetitive allele-specific PCR (KASP) markers. Within the interval, twenty-nine high-confidence genes were predicted according to Chinese Spring RefSeq v2.1. TraesCS5B03G0887500, encoding a serine/threonine protein kinase, was identified as the most likely candidate gene for QMS-5B based on weighted gene co-expression network analysis. Expression analysis confirmed that TraesCS5B03G0887500 was significantly differentially expressed in anthers of BS462 and CP279 at different stages under fertile and sterile environments. In addition, flanking KASP marker KASP-5B6 can effectively genotype male sterile lines and restorer lines, and can be used for molecular marker-assisted selection. This study provides insights into for exploring the mechanism of photo-thermo-sensitive genic male sterility in wheat.
QMS-5B 是小麦光温敏雄性不育的一个主要数量性状位点（QTL），被精细定位在一个包含丝氨酸/苏氨酸蛋白激酶基因 TraesCS5B03G0887500 的 2.15 Mb 区域内，该基因是最可能的候选基因。雄性不育是小麦杂种优势利用和杂交种子生产的重要特性。目前，已经在小麦突变体中报道了雄性不育基因，但控制小麦光温敏雄性不育的不育基因尚未得到系统研究。在这里，利用来自光温敏雄性不育系 BS462 和其恢复系 CP279 的杂交衍生的 235 个加倍单倍体（DH）系，通过 GenoBaits®小麦 100K 面板、Bulked Segregant Exome Sequencing（BSE-Seq）和小麦 660K 阵列对雄性不育基因进行了定位。结果表明，在所有四个环境中，第 5B 染色体上的主要稳定 QTL，即 QMS-5B，被鉴定出来，占表型方差的 7.3-36.4%。进一步地，通过使用竞争性等位基因特异性 PCR（KASP）标记，将 QMS-5B 限定在 KASP-5B5 和 KASP-5B6 之间约 2.15 Mb 的物理区间内。在这个区间内，根据中国春 RefSeq v2.1 预测了 29 个高可信度基因。TraesCS5B03G0887500 编码丝氨酸/苏氨酸蛋白激酶，根据加权基因共表达网络分析，被鉴定为 QMS-5B 最可能的候选基因。表达分析证实，TraesCS5B03G0887500 在不同环境下可育和不育条件下 BS462 和 CP279 花药不同阶段的表达存在显著差异。此外，侧翼 KASP 标记 KASP-5B6 可以有效地对雄性不育系和恢复系进行基因型鉴定，可用于分子标记辅助选择。这项研究为探索小麦光温敏雄性不育的机制提供了线索。
