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以小桐子(Jatropha curcas)c DNA为模版,克隆了Jc Ykt6基因的CDS序列。序列分析表明该基因包含600 bp完全阅读框(ORF),编码199个氨基酸。预测其编码蛋白质的分子量为22.53 k Da,等电点为6.90。Blast搜索结果及进化分析结果表明,Jc Ykt6蛋白与香瓜和黄瓜的Ykt6蛋白序列一致性最高(91%),亲缘关系最近。该基因编码的蛋白具有一个典型的VAMP基元。定量分析结果显示,Jc Ykt6基因在小桐子根、茎、叶、花、果皮和种子中都有表达,并且在种子中表达量最高。在种子生长发育的前期其表达水平不断增加,在种子生长发育的后期(50 d)达到最高值,然后下降。表达量变化过程与种子中储藏蛋白质合成趋势基本一致,推测其参与小桐子种子储藏蛋白质的合成和运输。ABA、PEG、Na Cl、4°C和机械损伤处理下Jc Ykt6表达水平都不同程度上调,推测Jc Ykt6具有多种功能,可能参与小桐子非生物胁迫响应和激素信号传导。
The CDS sequence of Jc Ykt6 gene was cloned from Jatropha curcas cDNA. Sequence analysis showed that the gene contained a 600 bp ORF encoding 199 amino acids. The molecular weight of the predicted protein was predicted to be 22.53 kDa and the isoelectric point was 6.90. Blast search results and phylogenetic analysis showed that JcYkt6 protein had the highest identity (91%) with Ykt6 protein sequence of melon and cucumber, and the closest genetic relationship. The protein encoded by this gene has a typical VAMP motif. Quantitative analysis showed that the Jc Ykt6 gene was expressed in the roots, stems, leaves, flowers, pericarp and seeds of Jatropha curcas, and the highest expression was found in the seeds. At the early stage of seed growth, its expression level increased continuously and reached the highest value at the later stage of seed growth (50 d), then decreased. The change of expression level was basically the same as that of stored protein in seeds, suggesting that it was involved in the synthesis and transportation of seed storage proteins of Jatropha curcas. The expression levels of Jc-Ykt6 in ABA, PEG, NaCl, 4 ° C and mechanical injury treatments were all up-regulated to some extent. It is speculated that Jc-Ykt6 has multiple functions and may be involved in the abiotic stress response and hormone signaling in Jatropha curcas.