Plant Physiol:华南农大刘向东研究组发表水稻相关研究文章
近日，国际著名植物学期刊plant Physiology上在线发表华南农业大学亚热带农业生物资源保护与利用国家重点实验室稻种资源保护与利用课题组刘向东教授和卢永根院士为通讯作者的研究论文“Polyploidy enhances F1 pollen sterility loci interactions that increase meiosis abnormalities and pollen sterility in autotetraploid rice”。该论文第一作者是该实验室刘向东教授指导的博士毕业生吴锦文，共同第一作者为Muhammad Qasim Shahid(华南农业大学外籍专业教师)。
研究是在课题组长期开展同源四倍体水稻研究的基础上，以张桂权教授提供的杂种花粉不育基因近等基因系加倍成的特殊同源四倍体水稻材料组配携带多座位互作的F1为材料，对其花粉母细胞减数分裂期间染色体行为和基因表达谱差异进行研究，发现多倍性显著加强了杂种花粉不育基因多座位互作的效应，使F1减数分裂异常性增加，包括55个减数分裂相关或时期特异表达的基因以及7个光合作用系统I等在内的重要基因都显著下调，其中编码DNA修复重组蛋白基因Os02g0497500和泛素蛋白酶体基因Os02g0490000下调十分明显，严重影响减数分裂相关基因网络的协调性，导致F1花粉育性严重偏低。该研究结果为进一步开展杂种花粉不育基因多座位互作效应的分子机理和克服其不育性提供理论基础。
原文链接：
Polyploidy enhances F1 pollen sterility loci interactions that increase meiosis abnormalities and pollen sterility in autotetraploid rice
原文摘要：
Intersubspecific (indica×japonica) autotetraploid Oryza sativa (rice) hybrids have greater biological and yield potentials than do diploid rice. However, the low fertility of intersubspecific autotetraploid hybrids, which is largely due to high pollen abortion rates, limits their commercial utility. To decipher the cytological and molecular mechanisms underlying allelic interactions in autotetraploid rice, we developed an autotetraploid rice hybrid that was heterozygous (SiSj) at F1 pollen sterility loci (Sa, Sb, and Sc), using near iso-genic lines. Cytological studies showed that the autotetraploid had a higher percentage (>30%) of abnormal chromosome behavior and aberrant meiocytes (>50%) during meiosis than did the diploid rice hybrid control. Analysis of gene expression profiles revealed 1888 genes that were differentially expressed between the autotetraploid and diploid hybrid lines at the meiotic stage, among which 889 and 999 were up- and down-regulated, respectively. Of the 999 down-regulated genes, 940 were associated with the combined effect of polyploidy and pollen sterility loci interactions (IPE). Gene Ontology enrichment analysis identified a prominent functional gene class consisting of seven genes related to photosystem I (GO: 0009522). Moreover, 55 meiosis-related or meiosis-stage-specific genes were associated with IPE in autotetraploid rice, including Os02g0497500, which encodes a DNA repair-recombination protein, and Os02g0490000, which encodes a component of the ubiquitin-proteasome pathway. These results suggest that polyploidy enhances epistatic interactions between alleles of pollen sterility loci, thereby altering the expression profiles of important meiosis-related or meiosis-stage-specific genes, and resulting in high pollen sterility.
作者：刘向东
