Holmes D I, Wahab N A, Mason R M
Division of Biomedical Sciences, Imperial College School of Medicine, BMS Building, South Kensington, London, SW7 2AZ, United Kingdom.
Genomics. 1999 Aug 15;60(1):105-9. doi: 10.1006/geno.1999.5897.
We report the cDNA cloning and characterization of ZNF236, a novel Kruppel-like zinc-finger gene initially identified by its glucose-regulated expression in human mesangial cells using mRNA differential display. Using the differential display fragment as a probe, we screened a human fetal kidney cDNA library and isolated several clones representing two differently spliced mRNA transcripts, designated ZNF236a and -b. Both transcripts were identical apart from the presence of an additional exon in ZNF236a that truncates the open reading frame. RT-PCR analysis confirmed the expression of both transcripts to be upregulated in human mesangial cells in response to elevated levels of d-glucose. ZNF236a and -b cDNAs encode polypeptides of 174 and 204 kDa, containing 25 and 30 C(2)H(2) zinc-finger motifs, respectively. Northern blot analysis showed that ZNF236 is ubiquitously expressed in all human tissues tested. Expression levels were highest in skeletal muscle and brain, intermediate in heart, pancreas, and placenta, and lowest in kidney, liver, and lung. Southern zoo blot analysis indicated that ZNF236 is conserved in the genomes of all mammalian species tested, but not in yeast. The mapping of ZNF236 to human chromosome 18q22-q23, close to the IDDM6 locus, coupled with the glucose-regulated expression of the gene in human mesangial cells, suggests that ZNF236 may be a candidate gene for diabetic nephropathy.
我们报道了ZNF236的cDNA克隆及特性分析，ZNF236是一种新的类 Kruppel 锌指基因，最初通过mRNA差异显示技术在人系膜细胞中发现其受葡萄糖调节表达。以差异显示片段为探针，我们筛选了人胎儿肾cDNA文库，分离出几个代表两种不同剪接的mRNA转录本的克隆，命名为ZNF236a和 -b。除了ZNF236a中存在一个额外的外显子导致开放阅读框截断外，两种转录本是相同的。RT-PCR分析证实，在d-葡萄糖水平升高时，人系膜细胞中两种转录本的表达均上调。ZNF236a和 -b cDNA分别编码174 kDa和204 kDa的多肽，分别含有25个和30个C(2)H(2)锌指基序。Northern印迹分析表明，ZNF236在所检测的所有人类组织中均有广泛表达。在骨骼肌和脑中表达水平最高，在心脏、胰腺和胎盘中表达水平中等，在肾脏、肝脏和肺中表达水平最低。Southern杂交分析表明，ZNF236在所检测的所有哺乳动物基因组中保守，但在酵母中不保守。ZNF236定位于人染色体18q22 - q23，靠近IDDM6位点，再加上该基因在人系膜细胞中的葡萄糖调节表达，提示ZNF236可能是糖尿病肾病的候选基因。
