Vendeland S C, Beilstein M A, Yeh J Y, Ream W, Whanger P D
Department of Agricultural Chemistry, Oregon State University, Corvallis 97331, USA.
Proc Natl Acad Sci U S A. 1995 Sep 12;92(19):8749-53. doi: 10.1073/pnas.92.19.8749.
Rat skeletal muscle selenoprotein W cDNA was isolated and sequenced. The isolation strategy involved design of degenerate PCR primers from reverse translation of a partial peptide sequence. A reverse transcription-coupled PCR product from rat muscle mRNA was used to screen a muscle cDNA library prepared from selenium-supplemented rats. The cDNA sequence confirmed the known protein primary sequence, including a selenocysteine residue encoded by TGA, and identified residues needed to complete the protein sequence. RNA folding algorithms predict a stem-loop structure in the 3' untranslated region of the selenoprotein W mRNA that resembles selenocysteine insertion sequence (SE-CIS) elements identified in other selenocysteine coding cDNAs. Dietary regulation of selenoprotein W mRNA was examined in rat muscle. Dietary selenium at 0.1 ppm as selenite increased muscle mRNA 4-fold relative to a selenium-deficient diet. Higher dietary selenium produced no further increase in mRNA levels.
大鼠骨骼肌硒蛋白W的互补脱氧核糖核酸（cDNA）被分离并测序。分离策略包括根据部分肽序列的反向翻译设计简并聚合酶链反应（PCR）引物。用大鼠肌肉信使核糖核酸（mRNA）的逆转录偶联PCR产物筛选从补充硒的大鼠制备的肌肉cDNA文库。该cDNA序列证实了已知的蛋白质一级序列，包括由TGA编码的一个硒代半胱氨酸残基，并确定了完成蛋白质序列所需的残基。RNA折叠算法预测硒蛋白W mRNA的3'非翻译区存在一个茎环结构，类似于在其他硒代半胱氨酸编码cDNA中鉴定的硒代半胱氨酸插入序列（SE-CIS）元件。研究了大鼠肌肉中硒蛋白W mRNA的膳食调节情况。相对于缺硒饮食，以亚硒酸盐形式存在的0.1 ppm膳食硒使肌肉mRNA增加了4倍。更高的膳食硒水平并未使mRNA水平进一步升高。
