以玉米不育系C48-2及保持系N48-2为材料，利用PCR和RT-PCR技术克隆了嵌合orf118-b 并研究了 cox2 转录本的结构变化。orf118-b 是玉米C48-2线粒体基因组特有的嵌合 orf，并能在单核期花药中特异表达。cox2* 仅在N48-2单核期花药中特异表达，cox2* 是 cox2 基因转录本GRM ZM5G862955_T01的新注释，其5'UTR区域被延长。利用Real-Time qPCR检测了 cdpk 在不育系及保持系雄穗发育的花粉母细胞时期、四分体时期、单核期和双核期的基因表达水平。结果表明，cdpk 在C48-2的母细胞时期、四分体时期、双核期上调表达，在C48-2的单核期下调表达。这些发现为进一步探索玉米CMS-C核质互作导致花粉败育的分子机制提供参考。
orf118-b and cox2* were cloned from sterile line C48-2 and it maintainer line N48-2 in maize by PCR and RT-PCR.orf118-b is a specific chimeric open reading frame in mitochondria genome of CMS-C line. cox2* was special transcript of cox2 only in N48-2, based on the maize genomic database, 5'UTR region of the transcript was extended comparison to the existed annotation.Expression of cdpk between C-Type cytoplasmic male sterility line and maintainer line at the pollen mother cells(PMCs) stage, the tetrad stage, the uninucleate stage and the binuclear stage were determined using Real-Time PCR.The results showed that cdpk was up-regulated in C48-2 at mother cell stage, tetrad stage, the binuclear stage, but was down-regulated in C48-2 at binuclear uninucleate stage.This results provide foundation for further explaining molecular mechanism of CMS-C in maize.
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