Tosi M, Bovey R, Astolfi S, Bodary S, Meisler M, Wellauer P K
EMBO J. 1984 Dec 1;3(12):2809-16. doi: 10.1002/j.1460-2075.1984.tb02213.x.
The number of active Amy-2 genes has been estimated in strain CE/J mice which produce four distinct electrophoretic forms of alpha-amylase in their pancreas. cDNA cloning and DNA sequence analysis discloses five distinct mRNA sequences which differ by approximately 1% of their nucleotides. Two of these mRNAs specify the same protein. Changes in the nucleotide sequences result in amino acid replacements that alter the net charges of the deduced proteins. This has allowed a tentative assignment of individual mRNAs to isozymes detected by electrophoresis. Quantitative Southern blot hybridization using a DNA probe specific for the first exon of Amy-2 reveals the presence of greater than 10 Amy-2 related sequences per haploid CE/J genome. Models which could account for the mouse strain-specific differences with respect to the number of pancreatic alpha-amylase isozymes and their variable but genetically determined quantitative ratios are discussed.
已对CE/J品系小鼠中活性Amy-2基因的数量进行了估计，该品系小鼠的胰腺中可产生四种不同电泳形式的α-淀粉酶。cDNA克隆和DNA序列分析揭示了五种不同的mRNA序列，它们的核苷酸约有1%的差异。其中两种mRNA编码相同的蛋白质。核苷酸序列的变化导致氨基酸替换，从而改变了推导蛋白质的净电荷。这使得可以初步将各个mRNA与通过电泳检测到的同工酶进行对应。使用针对Amy-2第一个外显子的DNA探针进行定量Southern印迹杂交，结果显示每个单倍体CE/J基因组中存在超过10个与Amy-2相关的序列。文中讨论了一些模型，这些模型可以解释小鼠品系在胰腺α-淀粉酶同工酶数量及其可变但由基因决定的定量比例方面的特异性差异。
