Alahiotis S N, Onoufriou A, Fotaki M, Pelecanos M
Biochem Genet. 1983 Feb;21(1-2):199-211. doi: 10.1007/BF02395404.
Partially purified lactate dehydrogenase (LDH) from third-instar larvae displays two bands (one major and one minor) on polyacrylamide gels. Analogous preparations from pupae and adults exhibit three LDH-staining bands (one major and two minor) in a similar pattern. The migration of the major band is similar for larvae, pupae, and adults, while the two minor LDH bands of pupae and adults migrate more slowly than the minor larval band. It has been shown that larval LDH incubated with beta-nicotinamide adenine dinucleotide exhibits two additional minor bands with an electrophoretic mobility similar to that of the minor bands of both pupae and adults. The intensity of the minor larval LDH band (exhibited also by untreated preparations) is drastically reduced. This fact indicates that the life-cycle stage-dependent LDH isozymic distribution is possibly due to a posttranslational effect(s). Highly purified LDH from larvae, pupae, or adults, obtained by an affinity chromatography procedure, displays just one dispersed band, located in the area between the band 5 and the band 6 exhibited by crude extract preparations. These data, in combination with the lack of difference in catalytic properties among enzymes from larvae, pupae, and adults, suggest that LDH synthesis is controlled by the same single structural gene at all developmental stages.
从三龄幼虫中部分纯化的乳酸脱氢酶（LDH）在聚丙烯酰胺凝胶上显示出两条带（一条主带和一条次带）。来自蛹和成虫的类似制剂在类似模式下呈现出三条LDH染色带（一条主带和两条次带）。幼虫、蛹和成虫的主带迁移情况相似，而蛹和成虫的两条次要LDH带比幼虫的次要带迁移得更慢。已表明，与β-烟酰胺腺嘌呤二核苷酸孵育的幼虫LDH呈现出另外两条次要带，其电泳迁移率与蛹和成虫的次要带相似。幼虫次要LDH带的强度（未经处理的制剂也显示）大幅降低。这一事实表明，生命周期阶段依赖性的LDH同工酶分布可能是由于翻译后效应。通过亲和色谱法从幼虫、蛹或成虫中获得的高度纯化的LDH仅显示出一条分散带，位于粗提取物制剂显示的第5带和第6带之间的区域。这些数据，再加上幼虫、蛹和成虫的酶在催化特性上没有差异，表明LDH的合成在所有发育阶段都由同一个单一结构基因控制。
