东方蜜蜂微孢子虫KRAB-A蛋白的分子特性及系统进化分析

Analysis of molecular characteristics and phyletic evolution of Nosema ceranae KRAB-A protein

为明确KRAB-A的分子特性并进行东方蜜蜂微孢子虫与其他物种KRAB-A蛋白的系统进化分析,以期丰富KRAB-A的基本信息,使用NCBI数据库中的ORF工具预测KRAB-A蛋白的氨基酸序列。利用ExPASy网站上的相关软件预测和分析KRAB-A蛋白的亲水性、信号肽、磷酸化位点、二级结构及三级结构。通过Mega11.0软件采用邻接法构建基于KRAB-A蛋白的系统进化树。结果显示,KRAB-A基因可编码1018个氨基酸;KRAB-A蛋白的分子式为C5314H8526N1522O1556S43,分子量约为120.00kDa,等电点为9.33,脂溶系数为79.20,亲水性为-0.75;KRAB-A含有41个丝氨酸、21个酪氨酸和16个苏氨酸磷酸化位点,1个H2C2模体,但不含有信号肽;KRAB-A含44.40%的α-螺旋,5.40%的β-转角,16.50%的延伸及33.69%的无规卷曲;蜜蜂微孢子虫的1个KRAB-A蛋白(NAPIS_ORF00138)与明球囊霉的2个KRAB-A蛋白(RCL2_000589200和RCL2_003114000)中存在与东方蜜蜂微孢子虫KRAB-A蛋白中相同的H2C2模体;东方蜜蜂微孢子虫KRAB-A(AAJ76_2380003054)与其姐妹种蜜蜂微孢子虫KRAB-A(NAPIS_ORF01514)聚为一支。研究结果明确了东方蜜蜂微孢子虫KRAB-A基因的分子特性,揭示KRAB-A可能是一种亲水性蛋白和胞内蛋白,东方蜜蜂微孢子虫KRAB-A(AAJ76_2380003054)与蜜蜂微孢子虫KRAB-A(NAPIS_ORF01514)间具有很高的保守性,为进一步的功能研究提供依据。

To enrich the basic information of KRAB-A gene by analyzing the molecular characteristics of KRAB-A and performing phylogenetic analysis of KRAB proteins in N.ceranae and other species,the amino acids sequence of KRAB-A was predicted using ORF tool in NCBI database.Related software in ExPASy website were employed to predict and analyze the hydrophilicity,signal peptide,phosphorylation site,secondary structure and ter-tiary structure of KRAB-A.Phylogenetic tree based on KRAB-A protein was constructed by Mega 11.0 software using Neighbor-joining method.The results demonstrated that KRAB-A gene can encode 1018 amino acids;the molecular formula of KRAB-A protein was C5314H8526N1522O1556S43,the molecular weight was 120.00 kDa,the hydrophilic point was 9.33,the lipid solubility coefficient was 79.20,and the hydrophilicity was-0.75;KRAB-A contained 41 serine phosphorylation sites,21 tyrosine phosphorylation sites,16 threonine phosphorylation sites,one H2C2 motif,and no signal peptide;additionally,KRAB-A included 44.40%α-helix,5.40%β-turn,16.50%extension and 33.69%random coil;N.ceranae KRAB-A(AAJ76_2380003054),Nosema apis KRAB-A(NAPIS_ORF00138)and Rhizophagus clarus KRAB-A(RCL2_000589200 and RCL2_003114000)contained the same one H2C2 motif;N.ceranae KRAB-A(AAJ76_2380003054)and one N.apis KRAB-A(NAPIS_ORF01514)was clustered into one clade.Our results clarified the molecular characteristics of KRAB-A gene in N.ceranae,and revealed that N.ceranae KRAB-A may be a and hydrophilic and intracellular protein and N.ceranae KRAB-A(AAJ76_2380003054)and N.apis KRAB-A(NAPIS_ORF01514)was highly conservative,and provide a basis for further functional study.