柽柳泛素结合酶基因(E2s)的序列分析及功能验证

从柽柳(Tamarix androssowii)cDNA文库中测序得到一条长度为607bp、编码146个氨基酸的全长cDNA基因序列,对该基因序列进行生物信息学分析,确定其属于泛素结合酶(Ubiquitin conjugating enzyme,E2s)蛋白家族。采用根癌农杆菌介导法对烟草进行E2s基因的遗传转化,通过分子检测证明,该基因整合到烟草基因组中,并在mRNA水平上有不同程度的表达。对各转基因及非转基因对照烟草进行干旱胁迫处理,通过调查相对电导率和相对生长量的变化,研究E2s基因抗旱方面的功能。结果表明,在非干旱胁迫条件下,各转基因株系与对照烟草的相对电导率差异不明显,各株系的相对电导率随着干旱胁迫时间的延长均呈上升趋势,且均小于对照烟草;干旱胁迫20d时,各转基因株系的相对电导率平均为9.12%,非转基因烟草的相对电导率则为12.35%,并且非转基因烟草的相对生长量仅为45.4%,而各转基因株系的相对生长量平均为141.1%,说明E2s基因的导入提高了转基因烟草的耐旱性。

Sequence Analysis and Function Determination of E2s Gene from Tamarix androssowii

A gene cloned from Tamarix androssowii cDNA library is 607 bp in full-length and encodes 146 amino acid residues.It is determined that the gene is a member of E2s family according to bioinformatics analysis.Using Agrobacterium-mediated transformation systems,E2s gene was integrated into tobacco genome and expressed diversely in mRNA level by real-time quantitative RT-PCR.The drought resistance of E2s gene was studied in terms of relative electrical conductivity and relative growth of transgenic tobacco lines and control plants under drought stress conditions.Result shows that there is an unobvious difference in relative electrical conductivity between the transgenic tobacco lines and the control plants grown without drought stress.The relative electrical conductivity of the transformed lines is lower than that of the control line,and the conductivity increases along with the prolonging of the drought stress.Twenty days after drought stress treatment,the conductivity and relative growth of the transgenic tobacco lines were 9.12% and 45.4%,respectively,and those of the control line were 12.35% and 141.1%.It indicates that the expression of E2s gene from T.androssowii improves the drought resistance of transgenic tobacco.