蕨类植物问荆DEAD-box RNA解旋酶基因的克隆与分析

DEAD-box RNA解旋酶参与RNA多方面的代谢,在植物生长发育和逆境反应中起重要作用。本研究从蕨类植物问荆（Equisetum arvense）中克隆到一条DEAD-box RNA解旋酶c DNA全长序列,命名为EaRH1,并在Gen Bank注册登记（KJ734026）。序列分析显示：该c DNA全长3 230 bp,包含一个从487 bp到2 799 bp编码770个氨基酸的开放读码框,其对应的蛋白序列包含9个保守模块结构。EaRH1与其它物种DEAD-box RNA解旋酶蛋白序列比对结果显示：模块Ⅰa、Ⅱ和Ⅲ序列几乎完全相同,模块Q、Ⅰ和Ⅳ序列存在一些差异。EaRH1与江南卷柏（Selaginella moellendorffii）基因组一条假定序列相似度高达69%,其中相似度最高的区域集中在包含9个保守模块的结构域。系统进化树分析显示：EaRH1与拟南芥（Arabidopsis thaliana）DEAD-box RNA解旋酶At3g22320在氨基酸序列上有相对较高的同源性。序列结构比较和进化分析可推测出EaRH1可能参与植物体生长发育、miRNA生物合成、与RNA结合蛋白的相互作用和非生物胁迫应答。本文的研究为探索问荆DEAD-box RNA解旋酶的进一步功能提供参考。

Cloning and Characterization of DEAD-box RNA Helicases Gene from the Fern Equisetum arvense

DEAD-box RNA helicases play an important role in muhiple biological processes, including growth, de- velopment, stress response and metabolism of cell. A full-length eDNA of DEAD-box RNA helicase, named EaRH1, has been cloned from Equisetum arvense in this study （GenBank accession number： KJ734026）. Sequence analysis indicates that the eDNA of EaRH1 is 3 230 bp in full length, and contains an ORF region from 487 bp to 2 799 bp, encoding 770 amino acids. The corresponding protein includes 9 conserved mode structures. Comparison with the sequence of the DEAD-box RNA helicase of other species, it is showed that the sequence of Motif Ⅰ a, Motif Ⅱ and Motif Ⅲ are almost completely same while there are certain differences in sequence of Q motif, Motif Ⅰ and Motif Ⅳ. The similarity of the EaRH1 sequence with the hypothetical DEAD-box RNA helicase protein of Selaginella moellendorffii reaches 69%. And the highest sequence similarity is concentrated in the domain that includes 9 conserved motifs. Phylogenetic analysis of DEAD-box RNA helicases sequences from different plants indicates that Equisetum arvense is more closely related to a DEAD-box gene of Arabidopsis thaliana （At3922320）. It can be inferred from se- quence comparison and phylogenetic analysis that EaRH1 might be involved in growth and development, miRNA bio- genesis, interaction with RNA binding protein and abiotic stress responses. Our study provides references for further functional researches on DEAD-box RNA helicases of Equisetum arvense.