Well, they share that protein and it's very different from anything our bodies make.

它们都含有这种蛋白质，但与我们人体制造原肌球蛋白不同。

Specifically, that club-headed myosin wants to get all up-close-and-personal with the actin.

具体说，棒状头肌球蛋白想近距离接触肌动蛋白。

Like the actin and myosin in our muscles that enable us to move.

就像我们肌肉中肌动蛋白和肌球蛋白一样，它们使我们能够移动。

Actin and myosin, the proteins of muscles, permit those bodies to move around.

肌动蛋白和肌球蛋白， 肌肉蛋白质， 允许这些身体四处移动。

Now shrimp shellfish and dust mites are all invertebrates and all of them trigger allergies thanks to a protein called tropomyosin.

虾等甲壳类动和尘螨都是无脊椎动，它们之所以会触发过敏反应是因为一种叫做原肌球蛋白质。

They've got their own famous coupling — a pretty pair of tiny protein strands called actin and myosin.

它们有自己著名联结——一对漂亮微小蛋白质链，叫做肌动蛋白和肌球蛋白。

Then comes a brief period of contraction, when the myosin heads are binding, and pulling, and releasing, over and over, and the muscle fibers contract.

然后是短暂收缩，这时肌球蛋白头一遍又一遍地结合、拉动和释放，肌肉纤维收缩。

But the only myosin heads that can bind to those newly exposed sites are ones that are ready for action.

但是唯一能与这些新暴露结合肌球蛋白头是那些准备好行动。

When it unbinds, the resulting shape-change puts the tropomyosin bodyguards back into place.

当它解绑时，由此产生形状变化使原肌球蛋白保镖恢复原。

Namely, actin is blocked by a couple of protein bodyguards — called tropomyosin and troponin — which keep getting in the way.

也就是说，肌动蛋白会被蛋白质保镖阻断——原肌球蛋白和肌钙蛋白——它们一直碍事。

They're divided lengthwise into segments called sarcomeres, which contain two even tinier strands of protein — two different kinds of myofilaments called actin and myosin.

它们在纵向上被分成称为肌节分，其中包含两股更小蛋白质——两种不同肌丝称为肌动蛋白和肌球蛋白。

At this point, the myosin is totally stoked, because the bodyguards that have been frustrating it are in for a big, irresistible distraction.

在这一点上，肌球蛋白完全兴奋起，因为一直让它沮丧保镖会有一个巨大、不可抗拒分心。

A sarcomere contains both thin filaments, made up mostly of two light and twisty actin strands, and thick filaments, composed of thicker, lumpy-looking myosin strands.

肌节既包含细丝，主要由两条轻盈而扭曲肌动蛋白链组成，也包含粗丝，由更厚、看起块状肌球蛋白链组成。

When those channels are thrown open, the calcium stored inside rushes into the rest of the cell, and finally myosin is like, YES! Here we go!

当这些通道打开时，储存在其中钙会涌入细胞其余分，最后肌球蛋白就像，是！开始了！

So after all that, with the myosin primed for action and the bodyguards out of the way, the myosin finally binds to actin, and it is beautiful.

经过这一切，当肌球蛋白准备好行动，保镖离开，肌球蛋白最终与肌动蛋白结合，这真是太美了。

That tension means myosin and the calcium pumps are burning up the muscle cells' ATP, and the finite supply of ATP is what makes it impossible to maintain vigorous muscle activity indefinitely.

这种张力意味着肌球蛋白和钙泵正在燃烧肌肉细胞三磷酸腺苷，而三磷酸腺苷有限供应使得肌肉活动不可能无限期地保持旺盛。

But soon the fiber slides back down into the relaxation period, when the calcium gets pumped back into the sarcoplasmic reticulum, and the actin and myosin stop the binding cycle, and the muscle relaxes.

但很快，纤维滑回松弛期，此时钙被泵入肌浆网，肌动蛋白和肌球蛋白停止结合循环，肌肉放松。

We've learned a lot about skeletal muscle tissue — how it's striated, and contracts using the actin-myosin sliding filament dance you've heard so much about.

我们已经了解了很多关于骨骼肌组织知识——它是如何形成条纹，以及如何使用肌动蛋白-肌球蛋白滑动学说舞蹈进行收缩，你已经听说过很多了。

If another action potential travels down before that can happen, even more calcium gets released, which ends up exposing more actin for myosin to bind to, and that means more force in that fiber.

如果另一个动作电在此之前下降，更多钙被释放，最终暴露更多肌动蛋白结合肌球蛋白，这意味着纤维中有更多力量。

You'd also re-learn that your skeletal muscles are constructed like a rope made of bundles of protein fibers, and that the smallest strands are your actin and myosin myofilaments.

你还会重新了解到你骨骼肌就像一根由成束蛋白质纤维组成绳子，最小链是你肌动蛋白和肌球蛋白肌丝。