Strahler J R, Meisler M
Genetics. 1982 May;101(1):91-102. doi: 10.1093/genetics/101.1.91.
The genetic determinants of pancreatic amylase expression in YBR mice differ in two respects from those of other inbred strains. First, there are two nonallelic amylase isozymes present in YBR pancreas, while most mouse strains express a single pancreatic amylase protein. In addition, the in vivo rate of total pancreatic amylase synthesis is 50% of that in other strains. Both these traits are determined by genetic sites in the region of the Amy-2 locus on mouse chromosome 3. To determine the molecular basis for the presence of two isozymes in this strain, we have compared portions of their amino acid sequences. Two differences between isozymes A1 and B1 were identified among the 77 residues compared. This result demonstrates that two distinct amylase genes are expressed in YBR pancreas.
YBR小鼠胰腺淀粉酶表达的遗传决定因素在两个方面与其他近交系不同。首先,YBR小鼠胰腺中存在两种非等位淀粉酶同工酶,而大多数小鼠品系只表达一种胰腺淀粉酶蛋白。此外,胰腺淀粉酶的总合成体内速率是其他品系的50%。这两个性状均由小鼠3号染色体上Amy-2位点区域的基因位点决定。为了确定该品系中存在两种同工酶的分子基础,我们比较了它们的部分氨基酸序列。在比较的77个残基中,鉴定出同工酶A1和B1之间存在两个差异。这一结果表明,YBR小鼠胰腺中表达了两个不同的淀粉酶基因。