《植物生理学报》 2009, 45(3): 258-262

甜瓜EST 序列中微卫星的分布特征

胡建斌, 刘颖, 王兰菊, 李建吾*

河南农业大学园艺学院, 郑州 450002

通信作者：李建吾；E-mail: lijw555@sohu.com；Tel: 0371-63554959

摘　要：

GenBank 中 35 547 条甜瓜 EST 经去冗余处理后, 得到总长度为 250.3 Mb 的无冗余 EST 34 438 条。这些序列中有 2813 个微卫星简单重复序列(Simple sequence repeat, SSR), 分布于 2 107 条 EST 中, 出现频率为 8.16%, 平均分布距离为 8.90 kb。三核苷酸重复是主导重复类型, 占SSR 总数的47.14%; 其次是二核苷酸和单核苷酸重复, 分别占SSR 总数的20.72%和16.99%。AAG/TTC 是优势重复基元, 占微卫星总数的 29.26%, AG/CT 和 A/T 分别占 14.61% 和 16.25%。在所有的 SSR 中,重复次数为 4~10 次的占 70.32%, 长度为 12~20 bp 的占 51.12%。并对这些 SSR 的多态性潜能进行了评价。

关键词：甜瓜; EST序列; 微卫星; 特征

收稿：2008-11-27   修定：2009-01-08

资助：国家“863” 计划(2007AA10Z100)和河南农业大学博士启动基金(30400247)。

Characteristics of Microsatellites in Melon (Cucumis melo L.) EST Sequences

HU Jian-Bin, LIU Ying, WANG Lan-Ju, LI Jian-Wu*

College of Horticulture, Henan Agricultural University, Zhengzhou 450002, China

Corresponding author: LI Jian-Wu; E-mail: lijw555@sohu.com; Tel: 0371-63554959

Abstract:

34 438 melon expressed sequence tags (ESTs) were obtained after the removal of redundant sequences from 35 547 melon ESTs deposited in GenBank. In these ESTs, 2 813 microsatellites (simple sequence repeat, SSR) were tested and distributed in 2 107 ESTs. The occurrence frequency of SSR was 8.16% and the average distribution distance was 8.90 kb. Trinucleotide repeats were dominant repeat types and accounted for 47.14%. Dinucleotide and mononucleotide repeats accounted for 20.72% and 16.99%, respectively. AAG/TTC was most frequent repeat motif and accounted for 29.26% in all SSRs. AG/CT and A/T accounted for 14.61% and 16.25%, respectively. Among all SSRs, SSRs which repeated 4 to 10 times accounted for 70.32%, and SSRs which was 12 to 20 bp long accounted for 51.12%. The potential polymorphism of these SSRs was also analyzed.

Key words: melon (Cucumis melo L.); EST sequence; microsatellite; characteristic