Identification and characterization of novel variants of the thioredoxin reductase 3 new transcript 1 TXNRD3NT1
Identification and characterization of novel variants of the thioredoxin reductase 3 new transcript 1 TXNRD3NT1
复制标题
DOI：
10.1007/s00335-004-2416-y
复制
发表时间：
2005-01-01
期刊：
影响因子：
2.5
通讯作者：
Inoko, H
中科院分区：
文献类型：
--
作者：
Matsuzaka, Y;Okamoto, K;Inoko, H
我们已经确定并表征了一个新的基因序列，TXNRD 3 NT 1，其转录本，对应于EST AA 430236，被发现通过Affyssin DNA芯片分析在受影响的银屑病组织中显著下调。采用5 ′-和3 ′-RACE（rapid amplication of cDNA ends）技术，结合筛选角质形成细胞cDNA文库、设计合适的PCR引物、克隆扩增产物、测序和序列分析，获得TXNRD 3 NT 1的全长cDNA。由于该基因的一部分与先前描述的硫氧还蛋白还原酶3（TXNRD 3）基因重叠，我们将其命名为TXNRD 3 NT 1（TXNRD 3新转录本1）。该基因全长1133个核苷酸，含有25个1-bp的3-UTR和2个poly（A）信号变异体和2个poly（A）位点。TXNRD 3 NT 1 cDNA ORF编码133个氨基酸，前4个残基编码微管蛋白-P mRNA自调节信号。将cDNA核苷酸序列定位到人类基因组序列显示TXNRD 3 NT 1基因具有4个外显子，位于染色体3上的位置3q 21。TXNRD 3 NT 1基因的外显子1和2与硫氧还蛋白还原酶2基因的外显子15和16重叠，硫氧还蛋白还原酶2基因具有与TXNRD 3 NT 1不同的ORF。翻译起始密码子ATG位于TXNRD 3 NT 1基因的第3外显子。RT-PCR结果显示，TXNRD 3 NT 1基因的全长变体仅在30种不同组织中的4种组织（胰腺、食管、骨髓和角化细胞）中表达。在大多数其他组织中，转录物的异常和截短形式（即，缺失外显子3和部分外显子4）。银屑病与TXNRD 3 NT 1基因的单个微卫星标记之间的初步关联研究的结果表明，它可能不是银屑病的重要遗传决定因素。然而，我们不能排除TXNRD 3 NT 1基因内可能仍存在其他序列变异的可能性。对8例银屑病患者和8例健康对照的TXNRD 3 NT 1基因进行序列分析，发现了一些同义的SNPs，这些SNPs可能是未来疾病相关性研究的有用标记。
We have identified and characterized a new gene sequence, TXNRD3NT1, whose transcripts, corresponding to the EST AA430236, were found by Affymetrix DNA chip analysis to be significantly down regulated in affected psoriatic tissue. The full-length cDNA of TXNRD3NT1 was isolated and characterized by combining 5'- and 3'-RACE (rapid amplication of cDNA ends) with screening a keratinocyte cDNA library, designing appropriate PCR primers, cloning amplified products, sequencing, and sequence analysis. Because part of this gene overlaps the previously described thioredoxin reductase 3 (TXNRD3) gene, we have named it TXNRD3NT1 (TXNRD3 new transcript 1). The full-length TXNRD3NT1 cDNA has 1133 nucleotides with a 25 1-bp 3-UTR and 2 poly(A)signal variants and 2 poly (A) sites. The TXNRD3NT1 cDNA ORF encodes for 133 amino acids, with the first four residues coding for a tubulin-P mRNA autoregulation signal. Mapping the cDNA nucleotide sequence to the human genome sequence revealed that the TXNRD3NT1 gene has 4 exons located on Chromosome 3, at position 3q21. Exons I and 2 of the TXNRD3NT1 gene overlap with exons 15 and 16 of the thioredoxin reductase 2 gene which has different ORFs to that of TXNRD3NT1. The translation initiation codon ATG was found in exon 3 of the TXNRD3NT1 gene. RT-PCR showed that the full-length variant of the TXNRD3NT1 gene was expressed in only four issues (pancreas, esophagus, bone marrow, and keratino-cytes) of the 30 different tissues tested. In most other tissues, an aberrant and truncated form of the transcript (i.e., missing exon 3 and part of exon 4) was detected. The result of a preliminary association study between psoriasis and single microsatellite marker of the TXNRD3NT1 gene suggests that it may not be a significant genetic determinant of psoriasis. However, we cannot exclude the possibility that other sequence variants may still exist within the TXNRD3NT1 gene. Sequence analysis of the TXNRD3NT1 gene from 8 psoriasis patients and 8 healthy controls revealed a number of synonymous SNPs that may be useful markers for future disease association studies.