黄瓜扩张蛋白基因CsEXP10的克隆与表达

Cloning and Expression of Cucumber CsEXP10 Gene

以cDNA-AFLP差示片段的序列(CO434610)为基础,通过RACE延伸和与EST序列拼接,得到长度为1191bp的、包含完整3'末端的CsEXP10基因cDNA序列。Southern杂交结果表明,该基因在黄瓜基因组中以单拷贝形式存在。RT-PCR检测发现,该基因不在根、茎和叶中表达,而在果实中表达。Northern杂交显示,该基因在授粉后迅速生长的幼果中丰量表达,而在幼小子房、开花当天的未授粉子房和生长停止的果实中不表达,由此推测CsEXP10基因与授粉后黄瓜果实膨大生长有密切关系。

Basing on the fragment （CO434610） cloned from cDNA amplified fragment length polymorphism （cDNA-AFLP）, a 1 191-bp cDNA sequence of CsEXP10 with a complete 3＇ end was obtained via rapid amplification of cDNA ends （RACE） and getting spliced with an EST （AF319471） of the same gene （Fig.2）. Southern blotting analysis showed that CsEXP10 was a single copy gene in cucumber （Fig.5）. The transcripts of CsEXP10 were detected by RT-PCR only in young fruit 3 d after pollination, but not in root, stem, and leaf （Fig.4A）. At different developmental stages of fruit growth, Northern blotting demonstrated that CsEXP10 gene was expressed strongly in fruit 3 d and 10 d after pollination, especially the latter, but undetectable in ovaries of 2-3 cm in length and without pollination on the day flowering, and in fruits 26 d after pollination （Fig.4B）. It is suggested that CsEXP10 might be highly correlated with the expansive growth of cucumber fruit.