Elevated glucose alters global gene expression and tenascin-C alternative splicing in mesangial cells.
Elevated glucose alters global gene expression and tenascin-C alternative splicing in mesangial cells.
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DOI：
10.1016/j.mbplus.2020.100048
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发表时间：
2020-11
影响因子：
--
通讯作者：
Schwarzbauer JE
中科院分区：
文献类型：
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作者：
Vega ME;Finlay JB;Vasishtha M;Schwarzbauer JE
肾小球系膜细胞是肾小球中主要的细胞外基质（ECM）产生细胞，并且当暴露于升高的葡萄糖水平时，它们上调纤连蛋白（FN）和其他ECM蛋白的组装。已知葡萄糖浓度的增加会改变基因表达;在此，我们研究了系膜细胞中ECM产生增加与基因表达变化之间的联系。通过RNA测序比较在正常或高糖条件下生长的肾小球系膜细胞显示超过6000个基因的显著表达变化，并且当通过KEGG途径分析分组时，在前5个上调途径中鉴定出ECM-受体相互作用和粘着斑途径。值得注意的是腱生蛋白-C（TN-C）表达的显著增加，腱生蛋白-C是FN基质组装的已知调节剂。由于6个FNIII重复外显子的选择性剪接，小鼠TN-C具有多种同种型。除了高葡萄糖的转录增加外，通过选择性剪接的外显子包含也发生了变化，导致产生更高分子量的TN-C亚型。在正常葡萄糖中生长的肾小球系膜细胞分泌包含1 - 2个可变重复的小亚型，而在高葡萄糖中分泌估计包含5个重复的大亚型。与较小的亚型不同，在FN基质中未检测到较大的TN-C。TN-C亚型的这种变化可能影响FN基质组装的调节，并且以这种方式可能有助于在高糖条件下增加ECM积累。高糖改变培养的肾小球系膜细胞基因表达。RNA测序鉴定ECM蛋白和受体的表达增加。高糖通过选择性剪接改变腱生蛋白C亚型表达。检测大与小腱生蛋白-C同种型的差异ECM定位。腱生蛋白-C的转换可能有助于ECM在糖尿病肾小球中的积累。
Mesangial cells are the major extracellular matrix (ECM)-producing cells in the kidney glomerulus and, when exposed to elevated glucose levels, they up-regulate assembly of fibronectin (FN) and other ECM proteins. Increases in glucose concentration are known to alter gene expression; here we investigated the connection between increased ECM production and changes in gene expression in mesangial cells. Comparison of mesangial cells grown in normal or high glucose conditions by RNA-sequencing showed significant expression changes in over 6000 genes and, when grouped by KEGG pathway analysis, identified the ECM-receptor interaction and focal adhesion pathways among the top 5 upregulated pathways. Of note was the significant increase in expression of tenascin-C (TN-C), a known regulator of FN matrix assembly. Mouse TN-C has multiple isoforms due to alternative splicing of 6 FNIII repeat exons. In addition to the transcriptional increase with high glucose, exon inclusion via alternative splicing was also changed resulting in production of higher molecular weight isoforms of TN-C. Mesangial cells grown in normal glucose secreted small isoforms with 1–2 variable repeats included whereas in high glucose large isoforms estimated to include 5 repeats were secreted. Unlike the smaller isoforms, the larger TN-C was not detected in the FN matrix. This change in TN-C isoforms may affect the regulation of FN matrix assembly and in this way may contribute to increased ECM accumulation under high glucose conditions. Elevated glucose alters gene expression in cultured mesangial cells. RNA-sequencing identifies increased expression of ECM proteins and receptors. High glucose changes tenascin-C isoform expression by alternative splicing. Differential ECM localization is detected for large vs small tenascin-C isoforms. Switch in tenascin-C may contribute to ECM accumulation in the diabetic glomerulus.