利用乙醇脱氢酶基因证据揭示稻属CCDD异源四倍体中染色体组的起源

Origin of Genomes in Oryza Allotetraploids Revealed by Alcohol Dehydrogenase Gene Sequences Data

对稻属异源四倍体中染色体组C和D以及稻属现存的所有二倍体染色体组A、B、C、E、F的乙醇脱氢酶基因(Adh1)片段分别进行PCR扩增、克隆和序列测定,并以G染色体组序列作为外类群,采用PAUP运算软件中的简约性方法对所测定的序列进行了系统发育分析.结果表明:(1)3个CCDD四倍体是同一次杂交事件的产物;(2)四倍体中的C染色体组和亚洲二倍体中的C染色体组表现出更近的系统发育关系;(3)D染色体组和E染色体组表现出较近的亲缘关系,二者可能有共同的祖先.

In this paper, the sequences of the alcohol dehydrogenase（Adhl）gene from C and D genomes in Oryza allotetraploids are compared with the sequences from A, B, C, E and F genomes in extant diploids. The sequence from G genome is treated as the out-group. Their Adhl genes are amplified, cloned and sequenced. Phylogenetic analyses are performed by using the parsimony methods in PAUP software. The results indicate that（1）three allotetraploids with CCDD genome might originate from a single hybridization event; （2）The C genome within the tetraploids shows a closer phylogenetic relationship to the C genome in diploids from Asia; （3）The D genome shows a closer affinity to the E genome than the other genomes, which suggests that D and E genomes might have an common ancestor.