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PsbS蛋白在植物非光化学淬灭(NPQ)中发挥着重要作用。采用同源比对方法从毛竹(Phyllostachys edulis)全长cDNA文库中得到1个PsbS同源基因序列(FP091683),命名为PePsbS1。该基因全长1 069 bp,具有多种光应答元件和参与光应答的顺式作用元件。PePsbS1的开放阅读框为807 bp,编码一个268 aa的蛋白。蛋白结构分析表明,该蛋白由转导肽(53 aa)和成熟蛋白(215 aa)组成,成熟蛋白包含1个叶绿素a/b结合蛋白功能域、4个跨膜区;疏水性分析表明该蛋白组成氨基酸以疏水性氨基酸为主,占42.5%;Blastp分析发现该蛋白与玉米的一致性最高,达80.3%。构建含有PePsbS1编码成熟蛋白序列的原核表达载体pET23a-PePsbS1-mature,转化大肠杆菌,经IPTG诱导表达后进行SDS-PAGE电泳分析。结果表明,分离纯化获得目的蛋白的分子量约为28 kD,与预测PePsbS1编码成熟蛋白的大小相符。这将有助于对竹子PsbS蛋白结构与功能的深入研究。
PsbS protein plays an important role in plant non-photochemical quenching (NPQ). A PsbS homologous gene sequence (FP091683) was obtained from the full-length cDNA library of Phyllostachys edulis by homology alignment and named as PePsbS1. The gene is 1 069 bp in length and possesses a variety of light-responsive elements and cis-acting elements involved in photosynthesis. The open reading frame of PePsbS1 is 807 bp, encoding a 268 aa protein. Protein structure analysis showed that the protein consisted of a leader peptide (53 aa) and a mature protein (215 aa). The mature protein contained one chlorophyll a / b binding protein domain and four transmembrane domains. Hydrophobic analysis indicated that the protein The main amino acids were hydrophobic amino acids, accounting for 42.5%. Blastp analysis showed that the protein had the highest identity with maize (80.3%). The prokaryotic expression vector pET23a-PePsbS1-mature containing the mature protein sequence encoding PePsbS1 was constructed and transformed into Escherichia coli. After induced by IPTG, SDS-PAGE electrophoresis analysis was performed. The results showed that the molecular weight of the target protein isolated and purified was about 28 kD, which was consistent with the predicted size of the mature protein encoded by PePsbS1. This will help in-depth study of the structure and function of PsbS protein in bamboo.