Liao Cheng, Zhao Mu-Jun, Li Zai-Ping
State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai, China.
Yi Chuan Xue Bao. 2002 Oct;29(10):865-70.
A novel mouse gene mLPTS was cloned by EST assembling, RT-PCR and DNA sequencing. The gene fragment for mLPTS is 1244 bp in length, encoding a protein of 332 amino acids. The amino acid sequence of mLPTS has 78% homologue with that of LPTS gene, which is a novel liver cancer-related gene identified through positional candidate cloning stratage by our laboratory. The expression of LPTS gene was ubiquitous in normal human tissues, whereas levels appeared to be significantly reduced, or sometime undetectable in HCC cells and neoplastic tissues, and it might be involved in the negative regulation of cell proliferation. The expression of mLPTS gene was found in all mouse tissues analyzed, same with that of LPTS gene in human. There was only one transcript for mLPTS gene in mouse tissues. The phylogenetic tree was constructed through the amino acids sequence analysis and the study of the sequence homologue among different species. Next, mLPTS gene was cloned into green fluorescent protein eukarytic expression vector and then transfected into CHO cell line. The green fluorescent was mostly limited in the nucleolus, showing that the gene products of mLPTS in eukaryocytes were located in the nucleolus.
通过EST拼接、RT-PCR和DNA测序克隆了一个新的小鼠基因mLPTS。mLPTS的基因片段长度为1244 bp,编码一个由332个氨基酸组成的蛋白质。mLPTS的氨基酸序列与LPTS基因的氨基酸序列具有78%的同源性,LPTS基因是本实验室通过定位候选克隆策略鉴定的一个新的肝癌相关基因。LPTS基因在正常人体组织中普遍表达,而在肝癌细胞和肿瘤组织中其表达水平似乎显著降低,有时甚至检测不到,它可能参与细胞增殖的负调控。在所有分析的小鼠组织中均发现了mLPTS基因的表达,与人类LPTS基因的情况相同。小鼠组织中mLPTS基因只有一个转录本。通过氨基酸序列分析和不同物种间序列同源性研究构建了系统发育树。接下来,将mLPTS基因克隆到绿色荧光蛋白真核表达载体中,然后转染到CHO细胞系中。绿色荧光主要局限于核仁,表明mLPTS在真核细胞中的基因产物定位于核仁。