Mouse muscle nicotinic acetylcholine receptor gamma subunit: cDNA sequence and gene expression.
Mouse muscle nicotinic acetylcholine receptor gamma subunit: cDNA sequence and gene expression.
复制标题
小鼠肌肉烟碱乙酰胆碱受体γ亚基：cDNA序列和基因表达。
作者：
L. Yu;R. LaPolla;N. Davidson
编码小鼠烟碱乙酰胆碱受体（AChR）γ亚基前体的克隆已从源自小鼠肌原细胞系的cDNA文库中选择并测序。推导的蛋白质序列由22个氨基酸残基的信号肽和497个氨基酸残基的成熟γ亚基组成。有一个高度的序列之间的保守性，这个小鼠序列和公布的人类和小牛AChR γ亚基，并允许功能性氨基酸取代后，也更远的相关鸡和电鳐AChR γ亚基。在四个假定的疏水跨膜区中，序列保守程度特别高，支持这些结构域的分配。RNA印迹杂交表明，γ亚基的mRNA水平增加了30倍或更多的分化后的两个小鼠肌原性细胞系，BC 3 H-1和C2 C12，这表明在分化过程中的基因表达的变化的主要控制是在转录水平。发现一个cDNA克隆对应于含有两个尚未剪接的间插序列的部分加工的核转录物。
Clones coding for the mouse nicotinic acetylcholine receptor (AChR) gamma subunit precursor have been selected from a cDNA library derived from a mouse myogenic cell line and sequenced. The deduced protein sequence consists of a signal peptide of 22 amino acid residues and a mature gamma subunit of 497 amino acid residues. There is a high degree of sequence conservation between this mouse sequence and published human and calf AChR gamma subunits and, after allowing for functional amino acid substitutions, also to the more distantly related chicken and Torpedo AChR gamma subunits. The degree of sequence conservation is especially high in the four putative hydrophobic membrane spanning regions, supporting the assignment of these domains. RNA blot hybridization showed that the mRNA level of the gamma subunit increases by 30 fold or more upon differentiation of the two mouse myogenic cell lines, BC3H-1 and C2C12, suggesting that the primary controls for changes in gene expression during differentiation are at the level of transcription. One cDNA clone was found to correspond to a partially processed nuclear transcript containing two as yet unspliced intervening sequences.