Fine mapping and candidate gene analysis of hwh1 and hwh2, a set of complementary genes controlling hybrid breakdown in rice
Fine mapping and candidate gene analysis of hwh1 and hwh2, a set of complementary genes controlling hybrid breakdown in rice
复制标题
DOI：
10.1007/s00122-008-0740-4
复制
发表时间：
2008-05-01
影响因子：
5.4
通讯作者：
Koh, Hee-Jong
中科院分区：
文献类型：
--
作者：
Jiang, Wenzhu;Chu, Sang-Ho;Koh, Hee-Jong
籼粳亚种间杂交后代常出现杂种败育现象，即杂种后代生活力或育性降低，生长发育迟缓。我们检测到HB植物的F-8重组自交系之间的杂交籼稻品种密阳23，粳稻品种通88-7。HB植株表现出生长迟缓，分蘖和小穗较少。遗传分析表明，HB是由两个隐性基因，hwh 1和hwh 2，来自双方的父母，这是精细定位在2号染色体的短臂和近着丝粒区的长臂11，分别控制的互补作用。父母和HB植物之间的候选基因序列的比较显示，HWH 1编码一个假定的葡萄糖-甲醇-胆碱氧化还原酶与一个氨基酸的变化相比，HWH 1和HWH 2可能编码一个假定的己糖转运蛋白与6个氨基酸的插入相比，HWH 2。利用候选基因标记对这些等位基因在54个粳稻和籼稻品种中的分布进行了研究，结果表明，这两个位点可能与两个亚种间的生殖障碍有关。
Hybrid breakdown (HB), a phenomenon of reduced viability or fertility accompanied with retarded growth in hybrid progenies, often arises in the offspring of intersubspecific hybrids between indica and japonica in rice. We detected HB plants in F-8 recombinant inbred lines derived from the cross between an indica variety, Milyang 23, and a japonica variety, Tong 88-7. HB plants showed retarded growth, with fewer tillers and spikelets. Genetic analysis revealed that HB was controlled by the complementary action of two recessive genes, hwh1 and hwh2, originating from each of both parents, which were fine-mapped on the short arm of chromosome 2 and on the near centromere region of the long arm of chromosome 11, respectively. A comparison of the sequences of candidate genes among both parents and HB plants revealed that hwh1 encoded a putative glucose-methanol-choline oxidoreductase with one amino acid change compared to Hwh1 and that hwh2 probably encoded a putative hexose transporter with a six amino acid insertion compared to Hwh2. Investigation of the distribution of these alleles among 54 japonica and indica cultivars using candidate gene-based markers suggested that the two loci might be involved in developing reproductive barriers between two subspecies.