Martinez I, Christiansen J S, Ofstad R, Olsen R L
Institute of Fisheries Technology Research, Tromsø, Norway.
Eur J Biochem. 1991 Feb 14;195(3):743-53. doi: 10.1111/j.1432-1033.1991.tb15762.x.
The expression of myosin isoforms and their subunit composition in the white skeletal body musculature of Arctic charr (Salvelinus alpinus) of different ages (from 77-day embryos until about 5 years old) was studied at the protein level by means of electrophoretic techniques. Myosin from the white muscle displayed three types of light chain during all the developmental stages examined: two myosin light chains type 1 (LC1F) differing in both apparent molecular mass and pI, one myosin light chain type 2 (LC2F) and one myosin light chain type 3 (LC3F). The fastest-migrating form of LC1F seemed to be predominant during the embryonic and eleutheroembryonic periods. The slowest-migrating form of LC1F was predominant in the 5-year-old fish. Between 1 year and 4 years, both types of LC1F were present in similar amounts. Cardiac as well as red muscle myosin from 3-year-old fish had two types of light chain. The myosin light chains from atria and ventriculi were indistinguishable by two-dimensional electrophoresis, but were different from the myosin light chains from red muscle. Neither the light chains from cardiac nor red muscle were coexpressed with the myosin light chains of white muscle at any of the developmental stages examined. Two myosin heavy chain bands were resolved by SDS/glycerol/polyacrylamide gel electrophoresis of the extract from embryos. One of the bands was present in minor amounts. The other, and most abundant, band comigrated with the only band found in the extracts of white muscle myosin from older fish. One-dimensional Staphylococcus aureus V8 protease peptide mapping of these bands revealed some differences during development of the white muscle tentatively interpreted as follows. The myosin heavy chain band present in minor amounts in the embryos may represent an early embryonic form that is replaced by a late embryonic or foetal form in the eleutheroembryos. The foetal myosin heavy chain appears to be present until the resorption of the yolk sack and beginning of the free-swimming stage. A new form of myosin heavy chain, termed neonatal and probably expressed around hatching, is present until about 1 year of age.(ABSTRACT TRUNCATED AT 400 WORDS)
运用电泳技术，在蛋白质水平上研究了不同年龄（从77天的胚胎直至约5岁）的北极红点鲑（Salvelinus alpinus）白色骨骼肌中肌球蛋白同工型的表达及其亚基组成。在所检测的所有发育阶段，白色肌肉中的肌球蛋白均显示出三种类型的轻链：两种1型肌球蛋白轻链（LC1F），其表观分子量和pI均不同；一种2型肌球蛋白轻链（LC2F）和一种3型肌球蛋白轻链（LC3F）。迁移速度最快的LC1F形式在胚胎期和孵化后胚胎期似乎占主导地位。迁移速度最慢的LC1F形式在5岁的鱼中占主导地位。在1岁至4岁之间，两种类型的LC1F含量相似。3岁鱼的心脏和红色肌肉肌球蛋白有两种类型的轻链。心房和心室的肌球蛋白轻链通过二维电泳无法区分，但与红色肌肉的肌球蛋白轻链不同。在任何检测的发育阶段，心脏和红色肌肉的轻链均未与白色肌肉的肌球蛋白轻链共表达。通过对胚胎提取物进行SDS/甘油/聚丙烯酰胺凝胶电泳，分辨出两条肌球蛋白重链带。其中一条带含量较少。另一条也是含量最多的带与 older fish 白色肌肉肌球蛋白提取物中唯一发现的带迁移位置相同。对这些带进行一维金黄色葡萄球菌V8蛋白酶肽图谱分析，发现在白色肌肉发育过程中存在一些差异，初步解释如下。胚胎中含量较少的肌球蛋白重链带可能代表一种早期胚胎形式，在孵化后胚胎中被晚期胚胎或胎儿形式所取代。胎儿肌球蛋白重链似乎一直存在，直到卵黄囊吸收和自由游动阶段开始。一种新的肌球蛋白重链形式，称为新生儿型，可能在孵化前后表达，一直存在到约1岁。（摘要截断于400字）
