Regulation of expression of avian slow myosin heavy-chain isoforms.
Regulation of expression of avian slow myosin heavy-chain isoforms.
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禽类慢肌球蛋白重链亚型表达的调节。
DOI：
10.1042/bj2600449
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Zak,R
中科院分区：
文献类型：
--
作者：
Reid,SK;Kennedy,JM;Shimizu,N;Stewart,A;Vrbova,G;Zak,R
鸡的慢强直性背阔肌（ALD）含有两种异肌球蛋白，即SM-1和SM-2。两种亚型的比例随年龄而变化，SM-2表达以SM-1为代价增加。在机翼上施加载荷增加了SM-1更换的速度和程度。在这里，我们已经证明，通过去除1周龄鸡翅膀的远端部分来减少负荷，其效果与过载相反，因为它减缓了肌肉生长和SM-1消除的速率。先前加权1或3周的肌肉的实验性卸载减慢了肌肉的生长速度，随之而来的相对肥大的回归，但是，它并没有导致SM-1肌球蛋白的重新表达。这表明超负荷诱导的肌球蛋白表达变化不容易逆转。神经切片产生了意想不到的结果，因为它提前了肌球蛋白表达的正常发育转变，使SM-2亚型占优势，类似于肌肉过载的效果。
The slow tonic anterior latissimus dorsi (ALD) muscle of the chicken contains two isomyosins, namely SM-1 and SM-2. The proportions of the two isoforms change with age, SM-2 expression increasing at the expense of SM-1. Applying a load on the wing increases the rate and extent of SM-1 replacement. Here we have demonstrated that decreasing the load by removal of the distal portion of the wing in 1-week-old chickens had an effect opposite to that of overloading in that it slowed muscle growth and the rate of SM-1 elimination. Experimental unloading of muscles previously weighted for 1 or 3 weeks slowed the growth rate of muscles, with consequent regression of relative hypertrophy; however, it did not lead to the reexpression of SM-1 myosin. This indicates that the overload-induced changes in myosin expression are not readily reversible. Nerve section produced unexpected results, in that it advanced the normal developmental shift in myosin expression toward predominance of the SM-2 isoform, similar to the effect of muscle overload.