水稻亚种间杂种F1低温敏感不育基因的差异显示

为研究水稻籼粳杂种低温下的育性特点和特异基因表达，以孕穗期白天24℃，夜晚20℃的低温和正常温度下生长的籼粳杂种02428/3037 F1及其亲本幼穗为材料，开花期对亲本、处理和对照的花粉育性分别进行了观察，种子收获后考察了其结实率。结果表明，与对照相比，白天24℃夜晚20℃的低温处理使杂种的花粉育性和结实率明显降低，但对亲本的花粉育性和结实率影响不大。用12条锚定引物和18条随机引物共216对引物组合对总RNA反转录后的cDNA进行了PCR扩增，共有35条在处理和对照间可重复扩增的表达差异的条带。对克隆后的差异条带进行了测序和Blast，发现这些差异片段与一些幼穗发育的EST有很高的同源性，同源性均在99%以上。其中一个与位于水稻第一号染色体的过氧化物酶基因的部分片段有100%相似性，另一个与位于第十二号染色体上的蛋白磷酸化酶基因有99.99%的同源性，分别与两个LTSS 基因所在的染色体一致。Southern杂交显示它们均为单拷贝片段。这些基因的表达与关闭与籼粳杂种低温敏感不育可能有密切关系。

DDRT-PCR for the Low Temperature Sensitive Genes of the Indica-japonica Hybrid F1

The different expressing genes were studied between the hybrid F1 under the normal and low temperature condition. At same time, their pollen fertility and seed fertility ratio were investigated. The results were as following, under the treatment temperature (24℃ for day, and 20℃ for night) the pollen fertility and seed fertility ratios of the hybrid F1 decreased, but there are no influence on the parent lines. Among 216 DDRT-PCR reactions, there are 35 differentially expressed fragments which can be regenerated, and they are all cloned into pGEM-T Easy Vector. It was found that one of the fragments was similar to the Peroxidase gene located on the rice chromosome 1 completely, another fragment was partially similar to the protein Phosphorylase gene located on the rice chromosome 12 with 99.99% homology. They are all single copy fragments.