摘要
基于转录组测序的差异表达基因分析结果，采用生物信息学方法对白及β-葡萄糖苷酶基因（Bsbg）进行序列特征和功能预测分析。结果表明Bsbg全长1933 bp，包含完整的开放阅读框，共编码521个氨基酸。疏水性分析发现其编码了理论等电点（pI）为8.79的亲水蛋白，信号肽和亚细胞检测该蛋白含有信号肽序列和跨膜区以及47个潜在的磷酸化位点。对氨基酸序列分析发现，该蛋白包含Glyco_hydro_1家族蛋白的保守结构域和26个motif。进一步对其二级结构和3D结构进行了数据库比对和结构预测。进化树分析发现白及的BSBG蛋白与现有数据库中白山沉水樟的亲缘关系最近。本分析结果为白及β-葡萄糖苷酶的研究提供了基础数据，也为植物β-葡萄糖苷酶基因的分子研究提供了理论依据和基础资料。
关键词： 白及；β-葡萄糖苷酶基因；序列特征；功能预测
Abstract
Based on the results of differentially expressed genes analyzed by transcriptome sequencing, bioinformatics method was used to analyze the sequence characteristics and function prediction of a β-glucosidase geneinBletilla striata (Bsbg). The results showed that the length of Bsbg was 1933 bp, which contained a complete open reading frame and encoded 521 amino acids.Hydrophobicity analysis revealed that it encoded a hydrophilic protein with a theoretical isoelectric point (PI) of 8.79. The signal peptide and subcellular detection revealed that the protein contained a signal peptide sequence, a transmembrane region and 47 potential sites of phosphorylation. Amino acid sequence analysis revealed that the protein contained a conserved domain of Glyco_hydro_1 family with 26 motifs.Furthermore, database comparison and structure prediction were performed for the secondary structure and 3D structure. The phylogenetic tree analysis showed that the protein sequences of BSBG and β-glucosidase from Cinnamomum micranthum f. kanehiraewere clustered in the same branch.The results of this analysis provided a basic data for the study of B. striata β-glucosidase, and also provided a theoretical basis for the molecular study of β-glucosidase genes in plants.
Key words： Bletilla striata, β-glucosidase gene, sequence analysis, function prediction
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