权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

MOLECULAR BASIS OF NUCLEUS-CYTOPLASM HYBRIDS IN WHEAT THAT INDUCE STRUCTRUAL ALTERATIONS OF MITOCHONDRIAL GENOME AND TRANSCRIPTION PATTERNS OF MITOCHONDRIAL GENES

小麦中诱导线粒体基因组结构改变和线粒体基因转录模式的核-细胞质杂种的分子基础

基本信息

批准号：
07640824
负责人：
OGIHARA Yasunari
金额：
$ 1.47万
依托单位：
KIHARA INSTITUTE FOR BIOLOGICAL RESEARCH,YOKOHAMA CITY UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

项目摘要

Alloplasmic wheat, Triticum aestivum cv. Norin 26 with Aegilops crassa cytoplasm, shows photoperiod-sensitive cytoplasmic male sterility (PCMS). This alloplasmic line expresses pistillody of anthers only when grown in the long-day condition (>15 h light). To assess molecular basis of the PCMS system, we carried out Southern and Northern blot analyzes by using the mitochondrial DNAs and RNAs isolated from seedlings of alloplasmic lines showing various phenotypes for PCMS and probing them with twelve mitochondrial genes. All RFLP patterns of mitochondrial DNA from alloplasmic lines greatly differed from those of common wheat, and were slightly changed from those of their parental species, i.e., Ae.crassa. This indicates that nuclear substitutions between the related plant species induce the structural alterations of the mitochondrial genome. Furthermore, RFLP patterns of (cr)-N61 and FR-mutant probed with cox III and orf25 were identical with each other, but different from those of the other alloplasmic lines, indicating the nuclei of N61 and FR-mutant harbor some gene (s) that induces the structural alterations of the mitochondrial genome around the regions of coxIII and orf25 genes. The transcription patterns of atp6 and cob in Ae.crassa type were different from those of T.aestivum type. Furthermore, the orf25 transcript of alloplasmic wheats was about 300 nucleotides longer than that of euplasmic lines including the Ae.crassa pure line, suggesting that transcription patterns of orf25 are associated with the recovery from the PCMS phenomenon. These data clearly show the mutual cross-talk between the nuclear genome and chondriome. These observations raise the possibility that the dysfunction of mitochondria caused by the failure of a cooperative control of mitochondrial gene (s) expression influences the pathway of flower morphogenesis, especially in the organ identity step.

异源细胞质小麦（Triticum aestivum cv.）野林26具有粗厚山羊草（Aegilops crassa）细胞质，属光敏感型细胞质雄性不育。这种异质系只有在长日照条件下（> 15小时光照）才表现出花药的雌蕊化。为了评估PCMS系统的分子基础，我们进行了Southern和北方印迹分析，通过使用线粒体DNA和RNA分离的异源细胞质系的幼苗表现出各种表型的PCMS和探测它们与12个线粒体基因。异源细胞质系线粒体DNA的RFLP图谱与普通小麦有很大差异，与亲本相比略有变化，即：Ae.crassa.这表明相关植物物种之间的核替换诱导线粒体基因组的结构改变。此外，（cr）-N61和FR-突变体的cox Ⅲ和orf25的RFLP图谱完全相同，但与其他异质系的图谱不同，表明N61和FR-突变体的核内含有引起cox Ⅲ和orf25基因附近线粒体基因组结构改变的基因。粗糙山羊草类型中atp 6和cob的转录模式与普通小麦类型不同。此外，orf 25的转录本的异质小麦比包括粗厚山羊草纯系的真质系长约300个核苷酸，这表明orf 25的转录模式与PCMS现象的恢复有关。这些数据清楚地显示了核基因组和染色体组之间的相互干扰。这些观察结果提出了一种可能性，即线粒体基因表达的合作控制失败所造成的线粒体功能障碍影响花形态发生的途径，特别是在器官身份的步骤。