MOLECULAR-CLONING AND EXPRESSION OF CDNAS ENCODING HUMAN ALPHA-MANNOSIDASE-II AND A PREVIOUSLY UNRECOGNIZED ALPHA-MANNOSIDASE-IIX ISOZYME
MOLECULAR-CLONING AND EXPRESSION OF CDNAS ENCODING HUMAN ALPHA-MANNOSIDASE-II AND A PREVIOUSLY UNRECOGNIZED ALPHA-MANNOSIDASE-IIX ISOZYME
复制标题
DOI：
10.1073/pnas.92.25.11766
复制
发表时间：
1995-12-05
影响因子：
11.1
通讯作者：
FUKUDA, MN
中科院分区：
文献类型：
--
作者：
MISAGO, M;LIAO, YF;FUKUDA, MN
高尔基体α-甘露糖苷酶II（α-MII）是一种参与N-连接聚糖加工的酶。使用先前分离的鼠cDNA克隆作为探针，我们已经分离了包含人α-MII cDNA开放阅读框的cDNA克隆，并开始分离人基因组克隆。在基因组克隆的分离过程中，分离了与编码α-MII的基因相关的基因。发现一个这样的基因编码同工酶，命名为α-MII（x）。然后从人黑色素瘤cDNA文库中分离出编码alpha-MII（x）的5-kb cDNA克隆，然而，alpha-MII（x）和alpha-MII cDNA之间的比较表明，克隆的cDNA编码具有796个氨基酸残基的截短多肽，而alpha-MII由1144个氨基酸残基组成。为了重新评估α-MII（x）cDNA的序列，用淋巴细胞mRNA进行聚合酶链反应（PCR），PCR产物的序列与α-MII（x）基因组序列的比较显示，α-MII（x）转录物的选择性剪接可以产生编码1139个氨基酸的多肽的额外转录物。北方分析表明，在各种组织中转录的α-MII（x），表明α-MII（x）基因是管家基因。用含有全长开放阅读框的α-MII（x）cDNA转染COS细胞后，α-甘露糖苷酶活性增加。α-MII（x）基因定位于人染色体15 q25，而α-MII基因定位于5 q21 -22。
Golgi alpha-mannosidase II (alpha-MII) is an enzyme involved in the processing of N-Linked glycans. Using a previously isolated murine cDNA clone as a probe,,ve have isolated cDNA clones encompassing the human alpha-MII cDNA open reading frame and initiated isolation of human genomic clones. During the isolation of genomic clones, genes related to that encoding alpha-MII were isolated, One such gene was found to encode an isozyme, designated alpha-MII(x). A 5-kb cDNA clone encoding alpha-MII(x) was then isolated from a human melanoma cDNA library, However, comparison between alpha-MII(x) and alpha-MII cDNAs suggested that the cloned cDNA encodes a truncated polypeptide with 796 amino acid residues, while alpha-MII consists of 1144 amino acid residues. To reevaluate the sequence of alpha-MII(x) cDNA, polymerase chain reaction (PCR) was performed with lymphocyte mRNAs, Comparison of the sequence of PCR products with the alpha-MII(x) genomic sequence revealed that alternative splicing of the alpha-MII(x) transcript can result in an additional transcript encoding a 1139-amino acid polypeptide. Northern analysis showed transcription of alpha-MII(x) in various tissues, suggesting that the alpha-MII(x) gene is a housekeeping gene. COS cells transfected with alpha-MII(x) cDNA containing the full-length open reading frame shelved an increase of alpha-mannosidase activity, The alpha-MII(x) gene was mapped to human chromosome 15q25, whereas the alpha-MII gene was mapped to 5q21-22.