Analysis of CFTR transcripts in nasal epithelial cells and lymphoblasts of a cystic fibrosis patient with 621 + 1G-->T and 711 + 1G-->T mutations.
Analysis of CFTR transcripts in nasal epithelial cells and lymphoblasts of a cystic fibrosis patient with 621 + 1G-->T and 711 + 1G-->T mutations.
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对具有 621 个 1G-->T 和 711 个 1G-->T 突变的囊性纤维化患者的鼻上皮细胞和淋巴母细胞中的 CFTR 转录本进行分析。
DOI：
10.1093/hmg/2.6.683
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发表时间：
1993
影响因子：
3.5
通讯作者：
Tsui,LC
中科院分区：
文献类型：
--
作者：
Zielenski,J;Bozon,D;Markiewicz,D;Aubin,G;Simard,F;Rommens,JM;Tsui,LC
我们分析了囊性纤维化患者的CFTR mRNA群体，该患者为621 + 1G → T和711+1G→T突变杂合子。从该患者的鼻上皮细胞和EB病毒转化的淋巴母细胞中分离的总RNA进行逆转录，并通过聚合酶链反应扩增从基因外显子3延伸至外显子7的区域并进行分析。三个异常的产品进行了鉴定，这表明存在三个异常的转录本，其配置文件是相同的两种细胞类型。发现其中两种产物分别缺失外显子4或外显子5，如来自621+1G→T或711+1G→T等位基因的转录物所预期的。第三种产物显然是通过使用外显子4内的隐蔽剪接供体序列（TT 528/GTGAGG），在不存在标称剪接位点（在621+1G→T中）的情况下，来自选择性剪接的mRNA种类。尽管阅读框似乎在所有三种推定的转录物中被保留，但推定的第一和第二跨膜跨度的显著部分以及紧接其后的胞质结构域将从突变CFTR多肽（如果产生的话）中缺失。这些观察结果与该囊性纤维化患者的CFTR功能丧失一致。
We have analyzed the CFTR mRNA populations in a cystic fibrosis patient heterozygous for the 621 +1G→T and 711+1G→T mutations. Total RNA isolated from the nasal epithelial cells and Epstein—Barr virus-transformed lymphoblasts derived from this patient was reversely transcribed and a region extending from exon 3 to exon 7 of the gene was amplified by the polymerase chain reaction and analyzed. Three abnormal products were identified, suggesting the presence of three aberrant transcripts, and their profiles were identical in both cell types. Two of the products were found to be missing either exon 4 or exon 5 as anticipated from the transcripts from the 621+1G→T or 711+1G→T alleles, respectively. The third product was apparently derived from an alternatively spliced mRNA species in the absence of the nominal splice site (in 621+1G→T) through the use of a cryptic splice donor sequence (TT528/GTGAGG) within exon 4. Although reading frames appeared to be preserved in all three putative transcripts, significant portions of the presumed first and second transmembrane spans as well as the immediately following cytoplasmic domain would be deleted from the mutant CFTR polypeptides, if made. These observations are consistent with a loss of CFTR function in this cystic fibrosis patient.