Byun S J, Jang M K, Jeoung N H, Kim J Y, Park Y B
Department of Genetic Engineering, College of Natural Sciences, Kyungpook National University, Taegu, Korea.
Mol Cells. 1998 Dec 31;8(6):657-62.
Differentially expressed genes generated by cholesterol-loading in the culture medium of aortic smooth muscle cells (SMC) were screened using the DDRT-PCR technique in order to identify the genes that are possibly involved in the pathogenesis of atherosclerosis in the artery. Twenty-eight genes were initially isolated and three differentially expressed cDNAs were finally selected by Northern blot analysis. All three cDNAs were up-regulated (designated CRGSM-1 through -3) by the cholesterol-loading. Upon nucleotide sequencing and homology search in the databases, the first cDNA (CRGSM-1) had a high homology (97%) with the corresponding segment of the acyl-CoA synthetase II gene from rat brain, which participates in fatty acid synthesis. The second one (CRGSM-2) had a high homology (91%) with a part of Mus musculus (mouse) LIM protein 1, and with human skeletal muscle LIM-protein 1 genes (80%) and the third gene (CRGSM-3) had no significant homology match in the database. A full size cDNA isolated from the cDNA library of rat aortic smooth muscle cell using the CRGSM-2 as a probe was identified to have a high homology with muscle LIM protein (MLP). The isolated cDNA contained a segment of DNA that encodes for a zinc-finger motif and two LIM domains. Proteins bearing the LIM domain, defined as a unique double zinc-finger structure associated with a subclass of proteins involved in the determination of cell identity, cell differentiation and control of cell growth, have previously been suggested to play an important role in the pathogenesis of atherosclerosis by others.
为了鉴定可能参与动脉粥样硬化发病机制的基因，利用DDRT-PCR技术筛选了主动脉平滑肌细胞（SMC）培养基中胆固醇加载产生的差异表达基因。最初分离出28个基因，最终通过Northern印迹分析选择了3个差异表达的cDNA。所有3个cDNA在胆固醇加载后均上调（命名为CRGSM-1至-3）。经核苷酸测序和数据库同源性搜索，第一个cDNA（CRGSM-1）与大鼠脑酰基辅酶A合成酶II基因的相应片段具有高度同源性（97%），该基因参与脂肪酸合成。第二个（CRGSM-2）与小家鼠（小鼠）LIM蛋白1的一部分、人类骨骼肌LIM蛋白1基因具有高度同源性（91%），而第三个基因（CRGSM-3）在数据库中没有显著的同源匹配。以CRGSM-2为探针从大鼠主动脉平滑肌细胞cDNA文库中分离出的一个全长cDNA被鉴定与肌肉LIM蛋白（MLP）具有高度同源性。分离出的cDNA包含一段编码锌指基序和两个LIM结构域的DNA。带有LIM结构域的蛋白质被定义为一种独特的双锌指结构，与参与细胞身份确定、细胞分化和细胞生长控制的一类蛋白质相关，此前其他人曾认为其在动脉粥样硬化发病机制中起重要作用。
