Further evidence that the human MUC2 gene transcripts in the intestine and trachea are identical.
Further evidence that the human MUC2 gene transcripts in the intestine and trachea are identical.
复制标题
进一步证明人类MUC2基因在肠道和气管中的转录本是相同的。
DOI：
10.1042/bj3060311
复制
发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Sachdev,GP
中科院分区：
文献类型：
--
作者：
Shankar,V;Gilmore,MS;Sachdev,GP
人MUC2粘蛋白是迄今为止唯一被充分表征的肠粘蛋白。它有一个超过5000个氨基酸的巨大蛋白质骨架，可以分为三个主要的结构域。这些结构域中最长的是中央串联重复序列，两侧是富含cys的区域。MUC2的富含cys的区域在很大程度上由一个重复元件组成，该元件与prepro-von Willebrand因子的D结构域具有高度的序列相似性[1,2]。完整的cDNA序列可在genbank和EMBL数据库中找到，登录号为L2998。先前的研究[3-5]表明，MUC2肠道基因在气道中也有表达，而MUC2串联重复探针可以通过两个器官的mRNA产生多分散信号。此外，Gerard等人（[3]）从囊性纤维化气管文库中分离出部分cDNA，该文库完全由重复序列组成，与肠道MUC2转录物中的串联重复序列具有显著的一致性。多分散性是粘蛋白mRNA的典型特征，可能与大量粘蛋白mRNA[6]周转过程中选择性剪接或部分降解的影响有关。由于单个信息的组织特异性选择性剪接或组织特异性处理可能导致不同组织中相似但不相同的转录本，因此我们研究了气道中69 bp串联重复结构域外的MUC2粘蛋白序列是否与肠道中的相同。使用人气管mRNA在Uni-ZAP载体（Stratagene, La Jolla， CA， USA）上构建cDNA文库，使用寡核苷酸（dT）连接引物启动第一链合成，按照制造商的方案。文库筛选cDNA探针MP-4，全长598 bp，与核苷酸对应
The human MUC2 mucin has been the only well-characterized intestinal mucin to date. It has an enormous protein backbone of greater than 5000 amino acids that can be divided into three major structural domains. The longest of these domains is the central tandem repeat array, flanked on either side by Cys-rich regions. The Cys-rich regions of MUC2 consist, in large part, of a repetitive element with a high degree of sequence similarity to the D domains of prepro-von Willebrand factor [1, 2]. The complete cDNA sequence is to be found in theGenBank and EMBL data bases with the accession number L2998. Based on Northern-blot experiments with the MUC2 tandem repeat probe that produces a polydisperse signal with mRNA from both organs, previous studies [3-5] have shown that the MUC2 intestinal gene is also expressed in the airways. Also, Gerard et al.[3] isolated a partial cDNA from a cystic fibrosis tracheal library that consisted entirely of repetitive sequences and showed remarkable identity with the tandem repeats present in the MUC2 transcript in the intestine. Polydispersity is typical of mucin mRNA and may be related to the effect of alternative splicing or partial degradation during turnover of the large mucin mRNA [6]. Since tissue-specific alternative splicing or tissue-specific processing ofa singlemessage could lead to similar, but not identical, transcripts in different tissues, we investigated whether the MUC2 mucin sequence in the airways, outside of the 69 bp tandem repeat domain, is identical with that in the intestine. Human tracheal mRNA was used to construct a cDNA library in the Uni-ZAP vector (Stratagene, La Jolla, CA, USA) using an oligo (dT) linker-primer to initiate first-strand synthesis as per the manufacturers' protocol. The library was screened with the cDNA probe MP-4 of 598 bp, corresponding to nucleotide