Bright Yellow 2烤烟热激蛋白90生物信息学分析

摘要

[Objective]Bioinformatic analysis for heat shock protein 90(HSP90)of tobacco(Bright Yellow 2)was conducted to provide theoretical basis for revealing characteristics of tobacco leaf curing.[Method]The sequences of NtHSP-1,NtHSP-2 and NtHSP-3(respective GenBank accession number:BAL42333,BAL42332 and BAM24708), Bright Yellow 2 HSP90 protein members,were collected from NCBI. The physical and chemical properties,transmem-brane region,signal peptide,subcellular localization,secondary structure and tertiary structure prediction were analyzed by using bioinformatics software.[Result]Amino acid numbers of NtHSP-1,NtHSP-2 and NtHSP-3 were 812,811 and 699 respectively. The content of acidic amino acid was the majority,with glutamic acid(Glu)accounting for the highest content. Theoretical isoelectric points of them were all less than 5.00,and the secondary structures were mainlyα-helix (H)and irregular curl(C). NtHSP-1 and NtHSP-2 presented high hydrophilicity and stability. They belonged to secretory protein with anchor structure,and located in endoplasmic reticulum. Their tertiary structures were in"r"shape,having a Mg2+binding site,HATPase_c(ATPase)and top6b(DNA topoisomerase VI)functional domain inside N-end. NtHSP-3 was a non-secreted protein which located in chloroplast. Its tertiary structure was in"i"shape,containing a Mg2+binding site and HATPase_c functional domain at N-end.[Conclusion]NtHSP-1 and NtHSP-2 may be related to endurable curing potential of tobacco leaves during curing. NtHSP-3 may be related to easy curing potential of tobacco leaves during curing process.%[目的]分析Bright Yellow 2烤烟热激蛋白90(HSP90)的生物学信息,为揭示烘烤过程中烟叶的烘烤特性提供理论依据.[方法]从NCBI中获取Bright Yellow 2烤烟HSP90蛋白序列NtHSP-1、NtHSP-2和NtHSP-3(GenBank登录号分别为BAL42333、BAL42332和BAM24708),利用生物信息学软件对各序列进行理化特性、跨膜区、信号肽、亚细胞定位、二级结构和三级结构预测分析.[结果]Bright Yellow 2烤烟NtHSP-1、NtHSP-2和NtHSP-3的氨基酸数量分别为812、811和699个,均以酸性氨基酸含量较多,其中谷氨酸(Glu)含量最高,理论等电点均小于5.00,二级结构均以α-螺旋(H)和无规则卷曲(C)为主.NtHSP-1和NtHSP-2的亲水性较高,具有较高的稳定性,属于分泌蛋白,具有锚定结构,定位于内质网,其三级结构呈现"r"形,N端内部具有Mg2+结合位点、HATPase_c(ATP酶)和top6b(DNA拓扑异构酶VI)功能域;NtHSP-3为非分泌型蛋白,定位于叶绿体,三级结构呈现"i"形,N端含有Mg2+结合位点和HATPase_c功能域.[结论]NtHSP-1和NtHSP-2可能与烟叶耐烤性有关,而NtHSP-3可能与烟叶易烤性有关.