Molecular basis of photoperiod-sensitive cytoplasmic male sterility in wheat

小麦光周期敏感细胞质雄性不育的分子基础

• 批准号: 12460006
• 负责人: MURAI Kouji
• 金额: $ 5.63万
• 依托单位: Fukui Prefectural University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12460006/
• 关键词: wheat; cytoplasmic male sterility; pistillody; mitochondrial DNA; fertility-restoring gene; MADS box gene; nuclear-cytoplasm interaction; alloplasmic line

The alloplasrmic line of wheat cv. Norin 26 (N26) with the cytoplasm of a wild relative species Aegilops crass shows pistillody, homoerotic transformation of stamens into pistil-like structures, when grown under long-day conditions (>15 h light). This phenomenon was named photoperiod-sensitive cytoplasmic male sterility (PCMS) and studies to develop a new hybrid wheat production system. Contrary to N26, wheat cv. Chinese Spring (CS) does not show the PCMS because of the presence of Rfd1 gene located on the long arm of chromosome 7B. The objective of this research project is to elucidate the molecular basis of the PCMS.1. Pistillody in the linesA loss-of function study of Rfd1 using ditelosomic 7BL alloplasmic line revealed that the Ae. Crassa cytoplasm essentially induces the pistillody independent of long photoperiod. The fertility restoration under the short-day conditions in the alloplasmic N26 could be controlled by gene(s) preventing the influence of the Ae. Crassa cytoplasm which functions under short photoperiod.2. Wheat MADS box genesAnalyses of wheat MADS box genes revealed that the pistillody is caused by the deficiency of class B MADS box gene expression in the stamen primordia of the alloplasmic lines.3. Mitochondrial genes associated with the pistillodyA subtraction study indicated that coxl gene and atpA chimeric gene are preferentially expressed in the pistillody line. This suggests that these mitochondrial gene products are associated with the induction of pistillody in the alloplasmic lines.Hybrid wheat breeding using the PCMSAccording to the results of present research, the problems to be solved for practical hybrid wheat breeding were clarified.

小麦品种的异质系。 Norin 26 (N26) 具有野生近缘种 Aegilops crass 的细胞质，当在长日照条件（>15 小时光照）下生长时，显示出雌蕊，即雄蕊向雌蕊样结构的同性转化。这种现象被命名为光周期敏感细胞质雄性不育（PCMS）并研究开发新的杂交小麦生产系统。与 N26 相反，小麦 cv.由于位于7B染色体长臂上的Rfd1基因的存在，中国之春(CS)不显示PCMS。本研究项目的目的是阐明 PCMS 的分子基础。1．品系中的 Pistillody 使用双端体 7BL 异质品系对 Rfd1 进行功能丧失研究表明，Ae.粗糙细胞质本质上诱导雌蕊独立于长光周期。异质N26在短日照条件下的育性恢复可以通过防止Ae影响的基因来控制。短光周期下发挥作用的粗糙细胞质。2．小麦MADS盒基因对小麦MADS盒基因的分析表明，雌蕊是异质系雄蕊原基中B类MADS盒基因表达缺陷所致。 3．与雌蕊相关的线粒体基因消减研究表明coxl基因和atpA嵌合基因优先在雌蕊系中表达。这表明这些线粒体基因产物与异质系中雌蕊的诱导有关。利用PCMS进行杂交小麦育种根据目前的研究结果，阐明了实际杂交小麦育种中需要解决的问题。