中国樱桃泰山干樱S-RNase基因的克隆及序列分析

以中国樱桃品种泰山干樱为试材,利用李属植物C2、C5保守区引物,扩增花柱S-RNase基因,获得4个S等位基因,测序结果表明序列大小分别为:1608、950、796、504bp。根据同源比较发现大小为796bp的等位基因与基因库中登录的S1-RNase为同一基因,其它3个S-RNase基因为首次报道,依序列大小分别命名为S2(1608bp,登陆号EF541168)、S4(950bp,登陆号EF541173)和S6(504bp,登陆号EF541172)。序列分析表明S2-RNase在C3区存在终止密码子,导致翻译提早终止;S4-RNase的C5区前有插入片断;S6-RNase在高变区比其它S等位基因少一个氨基酸残基。氨基酸序列同源性比较分析表明,中国樱桃S-RNase与樱花、扁桃的相似性高。在系统进化树中中国樱桃的4个S-RNase基因的氨基酸序列和樱花、扁桃、甜樱桃、酸樱桃等一起归于李亚科。

Cloning and sequence analysis of S-RNase gene in tetraploid Chinese cherry of Taishanganying(Prunus pseudocerasus)

Four specific fragments were isolated from Chinese cherry Taishanganying with conserved C2 and C5 primer in Prunus by allele-special PCR. The results of sequencing showed that they encoded 1 608,950,796,504 bp, respectively. Blastn research showed that one S-RNase of 796 bp was identical to S1-RNase gene, the other three S-RNase genes were reported firstly. We submitted three new S-RNase genes to the Genbank and denoted them as S2 (1 608 bp, accession number EF541168), S4 (950 bp, accession number EF541173), and S6 (504 bp, accession number EF541172). Terminate codon, which leading translation stop ahead, was found in C3 region of S2-RNase; fragment insert located before the C5 region of S4-RNase and one amino acid deleted in RHV region of S6-RNase accoding to the analysis of amino acid sequences. Four S-RNases of Chinese cherry revealed higher sequence identities with Japanese flowering cherry and almond, further grouped as sub-Family of Prunus along with Japanese flowering cherry, almond, sour cherry and sweet cherry in phylogentic tree based on amino acid sequences alignment.