Extracellular region of TRAIL has protein-enzyme site and forms a soluble molecule upon cleavage .

胞膜外区有蛋白酶作用位点，可以被从膜上剪切下来，形成可溶性分子。

youdao

So, this is called the extracellular region or domain, this is the trans-membrane region or domain, and this is the cytoplasmic region or domain.

因此,这部分叫做胞外区,中间这部分叫做跨膜区,内部这一段叫做胞质区

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