中文摘要：

LST8（lethal with SEC13 protein 8）是TOR（target of rapamycin）复合物的重要组成成分,在生物生长和发育的调控中发挥重要作用。本研究根据马氏珠母贝转录组数据库中注释为LST8的unigene序列设计引物,采用cDNA末端快速扩增（RACE）技术克隆获得了马氏珠母贝LST8基因cDNA全长序列（pm-LST8）;同时利用荧光定量PCR（Real-time PCR）技术检测了pm-LST8在马氏珠母贝各个组织中的表达含量。结果表明,pm-LST8基因cDNA全长1 350 bp,其中开放阅读框为948 bp,编码316个氨基酸残基,5＇UTR为104 bp,3＇UTR为298 bp,含有29 bp polyA。预测其分子量为35.4 kD,等电点为6.11。多序列比对显示pm-LST8与其它物种的LST8有较高的保守性,与牡蛎的同源序列高达82%。蛋白质结构预测显示pm-LST8具有典型的WD40结构域。荧光定量PCR分析表明pm-LST8在马氏珠母贝闭壳肌、鳃、外套膜、肝胰脏、性腺、足、血淋巴七个组织中均有表达,其中在性腺中表达量最高。本研究为进一步阐述LST8在马氏珠母贝生长和发育调控中的作用提供理论基础。

英文摘要：

LST8, which is an important component in the TOR （target ofrapamycin） complexes, plays crucial roles in the biological proliferation and development. In this study, based on the unigene sequence annotated as LST8 in the transcriptome database ofPinctada martensii, using rapid amplification ofcDNA ends technology, the full length ofLST8 gene was obtained from Pinctada martensii （pm-LST8）. The obtained full length ofpm-LST8 cDNA was 1 350 bp, containing a 5＇ untranslated region （UTR） of 104 bp, a 3＇ UTR of 298 bp with 29 bp polyA tail, and an open reading frame （ORF） of 948 bp encoding 316 amino acid residues. The predicted molecular weight was 35.4 kD, isoelectric point was 6.11. Multiple sequence alignment indicated that LST8 was highly conservative among species and pm-LST8 had 82% sequence identity with Crassostrea gigcts. Meanwhile, real-time PCR analysis demonstrated that pm-LST8 was constitutively expressed in all studied tissues in Pinctacla martensii with the most abundant mRNA in the sexual gland.