Regulation of endothelial cell glyceraldehyde-3-phosphate dehydrogenase expression by hypoxia.
Regulation of endothelial cell glyceraldehyde-3-phosphate dehydrogenase expression by hypoxia.
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DOI：
10.1016/s0021-9258(19)51104-8
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发表时间：
1994-09
期刊：
影响因子：
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通讯作者：
K. K. Graven-K.;R. Troxler;H. Kornfeld;M. V. Panchenko;H. Farber
中科院分区：
文献类型：
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作者：
K. K. Graven-K.;R. Troxler;H. Kornfeld;M. V. Panchenko;H. Farber
内皮细胞（EC）暴露于缺氧导致一组不同的蛋白质表达增加，分子量为56，47，39，36和34 kDa。它们的诱导似乎是EC和氧张力降低的应力所独有的。为了理解这些蛋白质上调的机制和意义，我们通过有限的氨基末端氨基酸测序鉴定了36-kDa蛋白质。来自牛蛋白的21个氨基酸序列与糖酵解酶甘油醛-3-磷酸脱氢酶（GAPDH）的人序列具有90.5%的同一性。北方印迹分析表明EC GAPDH mRNA表达上调的时间过程和程度与36-kDa蛋白合成的增加相关。核径流分析表明，GAPDH表达的增加部分是在转录水平上受到调节的;然而，转录速率的增加并不能解释整个mRNA的积累，这表明GAPDH与其他缺氧调节蛋白一样，受到转录后调节。缺氧EC的亚细胞分级显示上调的36-kDa蛋白质的细胞质部分，并在较小程度上，在核部分。GAPDH在EC中的表达上调可能与EC的相对耐缺氧能力有关。另外，缺氧时EC中GAPDH的上调可能与该酶潜在的非糖溶功能有关。
Exposure of endothelial cells (EC) to hypoxia results in the increased expression of a distinct set of proteins with molecular masses of 56, 47, 39, 36, and 34 kDa. Their induction appears to be unique to EC and the stress of decreased oxygen tension. To understand the mechanism(s) and significance of the up-regulation of these proteins we have identified the 36-kDa protein by limited amino-terminal amino acid sequencing. The 21-amino acid sequence from the bovine protein exhibited 90.5% identity with the human sequence of the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Northern blot analysis showed that the time course and extent of EC GAPDH mRNA up-regulation correlated with the increase in 36-kDa protein synthesis. Nuclear runoff analysis demonstrated that this increase in GAPDH expression is regulated, in part, at the transcriptional level; however, the increase in the rate of transcription did not account for the entire mRNA accumulation, suggesting that GAPDH, like other hypoxia-regulated proteins, is posttranscriptionally regulated. Subcellular fractionation of hypoxic EC showed up-regulation of the 36-kDa protein in the cytoplasmic fraction and, to a lesser extent, in the nuclear fraction. The up-regulation of GAPDH in EC may be related to their relative hypoxia tolerance. Alternatively, the up-regulation of GAPDH in EC during hypoxia may be related to the potential nonglycolytic functions of this enzyme.