Wright R M, Vaitaitis G M, Wilson C M, Repine T B, Terada L S, Repine J E
Webb-Waring Institute for Biomedical Research, University of Colorado Health Sciences Center, Denver 80262-0059.
Proc Natl Acad Sci U S A. 1993 Nov 15;90(22):10690-4. doi: 10.1073/pnas.90.22.10690.
We isolated cDNAs encoding xanthine dehydrogenase (XD; xanthine:NAD+ oxidoreductase, EC 1.1.1.204) from a human liver cDNA library. The complete nucleotide sequence of human XD was determined; the deduced amino acid sequence encoded a protein of 1336 amino acid residues of M(r) 147,782. Human XD possessed many of the signature sequences typical of XDs from flies and rodents, including an unusual cysteine distribution, a potential 2Fe/2S binding site, and a putative molybdopterin cofactor binding domain. Analysis of potential NAD binding sites suggested a simple hypothesis for the conversion of human XD into the oxygen metabolite forming xanthine oxidase (XO; xanthine:oxygen oxidoreductase, EC 1.1.3.22). Using a human XD complementary RNA hybridization probe, we found a 5100-base RNA in human liver by RNA blot-hybridization analysis. This RNA exhibited tissue-specific distribution that may be pertinent to XD- and XO-mediated oxygen radical injury in ischemia/reperfusion and inflammation. A second 4500-base RNA was detected in some tissues and may arise through differential transcription termination.
我们从人肝脏cDNA文库中分离出编码黄嘌呤脱氢酶（XD；黄嘌呤：NAD +氧化还原酶，EC 1.1.1.204）的cDNA。测定了人XD的完整核苷酸序列；推导的氨基酸序列编码一个由1336个氨基酸残基组成、分子量为147,782的蛋白质。人XD具有许多果蝇和啮齿动物XD典型的特征序列，包括不寻常的半胱氨酸分布、一个潜在的2Fe/2S结合位点和一个假定的钼蝶呤辅因子结合结构域。对潜在NAD结合位点的分析为将人XD转化为形成氧代谢物的黄嘌呤氧化酶（XO；黄嘌呤：氧氧化还原酶，EC 1.1.3.22）提出了一个简单的假说。使用人XD互补RNA杂交探针，我们通过RNA印迹杂交分析在人肝脏中发现了一个5100碱基的RNA。这种RNA表现出组织特异性分布，这可能与缺血/再灌注和炎症中XD和XO介导的氧自由基损伤有关。在一些组织中检测到第二种4500碱基的RNA，它可能是通过不同的转录终止产生的。
