期刊
MOLECULAR AND CELLULAR BIOLOGY
卷 22, 期 5, 页码 1402-1411出版社
AMER SOC MICROBIOLOGY
DOI: 10.1128/MCB.22.5.1402-1411.2002
关键词
-
资金
- NCI NIH HHS [CA80946, R01 CA080946] Funding Source: Medline
- NIGMS NIH HHS [GM61603, R01 GM061603] Funding Source: Medline
- NATIONAL CANCER INSTITUTE [R01CA080946] Funding Source: NIH RePORTER
- NATIONAL INSTITUTE OF GENERAL MEDICAL SCIENCES [R01GM061603] Funding Source: NIH RePORTER
Selenocysteine (Sec), the 21st amino acid in protein, is encoded by UGA. The Sec insertion sequence (SECIS) element, which is the stem-loop structure present in 3' untranslated regions (UTRs) of eukaryotic selenoprotein-encoding genes, is essential for recognition of UGA as a codon for See rather than as a stop signal. We now report the identification of a new eukaryotic selenoprotein, designated selenoprotein M (SelM). The 3-kb human SelM-encoding gene has five exons and is located on chromosome 22 but has not been correctly identified by either Celera or the public Human Genome Project. We characterized human and mouse SelM cDNA sequences and expressed the selenoprotein in various mammalian cell lines. The 3' UTR of the human, mouse, and rat SelM-encoding genes lacks a canonical SECIS element. Instead, See is incorporated in response to a conserved mRNA structure, in which cytidines are present in place of the adenosines previously considered invariant. Substitution of adenosines for cytidines did not alter See incorporation; however, other mutant structures did not support selenoprotein synthesis, demonstrating that this new form of SECIS element is functional. SelM is expressed in a variety of tissues, with increased levels in the brain. It is localized to the perinuclear structures, and its N-terminal signal peptide is necessary for protein translocation.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据