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cDNA全长序列，命名为EaRH1，并在GenBank注册登记（KJ734026）。序列分析显示：该cDNA全长3230bp，包含一个从487bp到2799bp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 multiple biological processes, including growth, development, stress response and metabolism of cell. A full length cDNA 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 cDNA of EaRH1 is 3230bp in full length, and contains an ORF region from 487bp to 2799bp, 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 Ⅰa, Motif Ⅱ and Motif Ⅲ are almost completely same while there are certain differences in sequence of Q motif, Motif Ⅰand 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 (At3g22320). It can be inferred from sequence comparison and phylogenetic analysis that EaRH1 might be involved in growth and development, miRNA biogenesis, 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.