Fine mapping of Helminthosporium turcicum resistance gene Ht2 is extremely valuable for map-based cloning of the Ht2 gene, gaining a better knowledge of the distribution of resistance genes in maize genome and marker-...Fine mapping of Helminthosporium turcicum resistance gene Ht2 is extremely valuable for map-based cloning of the Ht2 gene, gaining a better knowledge of the distribution of resistance genes in maize genome and marker-assisted selection in maize breeding. An F2 mapping population was developed from a cross between a resistant inbred line 77Ht2 and a susceptible inbred line Huobai. With the aid of RFLP marker analyses, the Ht2 gene was mapped between the RFLP markers UMC89 and BNL2.369 on chromosome 8, with a genetic distance of 0.9 cM to BNL2.369. There was a linkage between SSR markers UMC1202, BNLG1152, UMC1149 and the Ht2 gene by SSR assay. Among the SSR markers, the genetic distance between UMC1149 and the Ht2 gene was 7.2 cM. By bulked segregant analysis 7 RAPD-amplified products which were probably linked to the Ht2 gene were selected after screening 450 RAPD primers and converted the single-copy ones into SCAR markers. Linkage analysis showed that the genetic distance between the SCAR marker SD-06633 and the Ht2 gene was 0.4 cM. From these results, a part of linkage map around the Ht2 gene was constructed.展开更多
人类 Y 染色体上大部分的 DNA 为重复序列。这些重复 DNA 包括长插入因子和短插入因子及串连重复序列,前两者与逆转录机制有关;后者包括 Y 染色体特异性重复家族,相应的 Y 染包体特异性探针已被克隆和应用,高变串连重复 DNA 的重复拷贝...人类 Y 染色体上大部分的 DNA 为重复序列。这些重复 DNA 包括长插入因子和短插入因子及串连重复序列,前两者与逆转录机制有关;后者包括 Y 染色体特异性重复家族,相应的 Y 染包体特异性探针已被克隆和应用,高变串连重复 DNA 的重复拷贝数变异很大,其 RFLP 将为建立 Y染色体及基因组物理图和遗传图提供有意义的遗传标记。展开更多
基金This work was jointly supported by the National Transgenic Plant Research Foundation of China (Grant No. J00-A-002) and the National Research Foundation for Key Techniques (The Explo-ration and Application of Crop Resources,2001-2003,04-012) of China.
文摘Fine mapping of Helminthosporium turcicum resistance gene Ht2 is extremely valuable for map-based cloning of the Ht2 gene, gaining a better knowledge of the distribution of resistance genes in maize genome and marker-assisted selection in maize breeding. An F2 mapping population was developed from a cross between a resistant inbred line 77Ht2 and a susceptible inbred line Huobai. With the aid of RFLP marker analyses, the Ht2 gene was mapped between the RFLP markers UMC89 and BNL2.369 on chromosome 8, with a genetic distance of 0.9 cM to BNL2.369. There was a linkage between SSR markers UMC1202, BNLG1152, UMC1149 and the Ht2 gene by SSR assay. Among the SSR markers, the genetic distance between UMC1149 and the Ht2 gene was 7.2 cM. By bulked segregant analysis 7 RAPD-amplified products which were probably linked to the Ht2 gene were selected after screening 450 RAPD primers and converted the single-copy ones into SCAR markers. Linkage analysis showed that the genetic distance between the SCAR marker SD-06633 and the Ht2 gene was 0.4 cM. From these results, a part of linkage map around the Ht2 gene was constructed.
文摘人类 Y 染色体上大部分的 DNA 为重复序列。这些重复 DNA 包括长插入因子和短插入因子及串连重复序列,前两者与逆转录机制有关;后者包括 Y 染色体特异性重复家族,相应的 Y 染包体特异性探针已被克隆和应用,高变串连重复 DNA 的重复拷贝数变异很大,其 RFLP 将为建立 Y染色体及基因组物理图和遗传图提供有意义的遗传标记。
