东方蜜蜂微孢子虫20s PS基因的分子克隆与生物信息学分析

为解析东方蜜蜂微孢子虫Nosema ceranae的20s 蛋白酶体亚基（20s proteinsome submit, 20s PS）基因20s PS的分子特性，鉴定东方蜜蜂微孢子虫和其他物种的20s PS蛋白的保守基序和结构域并进行系统进化分析，通过常规PCR扩增20s PS的CDS区并进行TA克隆。通过Expasy网站上的相关软件预测和分析20s PS的理化性质、跨膜螺旋域、信号肽、磷酸化位点、二级结构和三级结构。采用MEME软件预测东方蜜蜂微孢子虫和其他物种20s PS的保守基序。利用TBtools软件预测东方蜜蜂微孢子虫和其他物种20s PS的结构域。使用Mega 11.0软件构建东方蜜蜂微孢子虫和其他物种的20s PS的系统进化树。成功克隆到东方蜜蜂微孢子虫20s PS的CDS区，20s PS在孢子中真实表达。20s PS基因含有618个核苷酸，可编码205个氨基酸；20s PS蛋白的分子式为C₁₀₂₂H₁₅₈₂N₂₆₀O₃₁₆S₁₂，分子量约为22.95 kDa，脂溶系数为78.93，等电点为5.00，平均亲水系数为-0.157；不含跨膜螺旋域和典型信号肽；包含14个丝氨酸酸化位点，5个络氨酸酸化位点及6个苏氨酸磷酸化位点；包含73个α-螺旋，46个延长链，21个β-转角和65个无规-则卷曲；可同时定位于细胞质、细胞核和线粒体；与模板5mp9.1.J之间的同源性为37.75%。东方蜜蜂微孢子虫、蚱蜢脑炎微孢子虫Encephalitozoon romaleae和肠脑炎微胞子虫Encephalitozoon intestinalis等7个物种的20s PS中均含有5个相同的保守基序（motif1, motif2, motif3, motif4和motif5）。东方蜜蜂微孢子虫、蜜蜂微孢子虫Nosema apis、杀线虫sp Nematocida sp、泛孢虫Pancytospora philotis和毕氏肠微孢子虫Pancytospora philotis的20s PS中均包含Ntn_hydrolase superfamily结构域。东方蜜蜂微孢子虫20s PS（XP_024330780.1）与蜜蜂微孢子虫20s PS（EQB61106.1）聚为一支，进化距离最近。研究结果丰富了东方蜜蜂微孢子虫20s PS的信息，并揭示20s PS可能是亲水性蛋白、胞内蛋白和非跨膜蛋白，东方蜜蜂微孢子虫与蜜蜂微孢子虫的20s PS之间的亲缘关系最近，20s PS在东方蜜蜂微孢子虫和其他微孢子虫中具有较高的保守性，为深入开展相关功能研究提供依据。

Molecular cloning and bioinformatic investigation of Nosema ceranae 20s PS gene

To decipher the molecular characteristics of 20s proteinsome submit gene 20s PS in Nosema ceranae, identify conserved motifs and structural domains and conduct phylogenetic analysis of 20s PS proteins in N. ceranae and other species, CDS region of 20s PS was amplified using conventional PCR followed by TA cloning. Physical and chemical property, transmembrane domain, signal peptide, phosphorylation site, secondary structure and tertiary structure were predicted and analyzed by relevant software on Expasy website. Conserved motifs within 20s PS in N. ceranae and other species were identified with MEME software. TBtools software was employed to predict structural