Yasuda Y, Miyata T, Nangaku M, Iida Y, Maeda K, Kurokawa K, Okubo K
Institute of Medical Science, Tokai University School of Medicine, Isehara, Japan.
Kidney Int. 1998 Jan;53(1):154-8. doi: 10.1046/j.1523-1755.1998.00751.x.
For normal physiological function, each cell tightly regulates gene expression in a specific fashion so that critical proteins are synthesized in a well-coordinated manner. Therefore, it is very important to uncover which genes are expressed in specific cells. Recent technological advances combined with rapid large-scale DNA sequencing and computerized data processing have allowed us to investigate the expression levels of a variety of transcripts in the mesangial cells, a target of injury in many forms of glomerulonephritis. Utilizing a large scale sequencing of a 3'-directed cDNA library, which allows us to avoid variable cloning efficiencies reflecting the size of cDNA, we investigated expression profiles of various molecules in cultured human mesangial cells. Among the 1,193 sequenced clones, 688 (57.7%) appeared more than once (redundant sequence group), representing 203 different species. Thirty-nine of these appeared more than three times. The most abundant mRNA was that of fibronectin, which consisted of 3.9% of the total mRNA population. Except for mitochondrial or ribosomal genes, calcyclin came next (2.5%), followed by two cytoskeletal genes, gamma-actin gene and calpactin 1 light chain gene, in addition to an amyloid precursor protein homolog (0.7%). In conclusion, we performed a molecular biological quantification of transcripts in mesangial cells. Fibronectin was the most abundantly expressed, followed by calcyclin, gamma-actin, calpactin 1 light chain, and an amyloid precursor protein homolog. We also discovered some candidate genes specific for human mesangial cells. The expression profile of the transcripts serves as an important tool in understanding the biological properties of mesangial cells.
为实现正常的生理功能，每个细胞都以特定方式严格调控基因表达，从而使关键蛋白得以协调合成。因此，揭示特定细胞中表达的基因非常重要。近期的技术进步与快速大规模DNA测序及计算机化数据处理相结合，使我们能够研究多种转录本在系膜细胞中的表达水平，系膜细胞是多种形式肾小球肾炎的损伤靶点。利用3'端定向cDNA文库的大规模测序，这种方法能避免因cDNA大小不同而导致的克隆效率差异，我们研究了培养的人系膜细胞中各种分子的表达谱。在1193个测序克隆中，688个（57.7%）出现不止一次（冗余序列组），代表203种不同的物种。其中39种出现超过三次。最丰富的mRNA是纤连蛋白的mRNA，占总mRNA群体的3.9%。除线粒体或核糖体基因外，钙周期蛋白次之（2.5%），其次是两个细胞骨架基因，γ-肌动蛋白基因和钙结合蛋白1轻链基因，还有一种淀粉样前体蛋白同源物（0.7%）。总之，我们对系膜细胞中的转录本进行了分子生物学定量分析。纤连蛋白表达最为丰富，其次是钙周期蛋白、γ-肌动蛋白、钙结合蛋白1轻链和淀粉样前体蛋白同源物。我们还发现了一些人系膜细胞特有的候选基因。转录本的表达谱是理解系膜细胞生物学特性的重要工具。
