查询词典 narrow passage gate

The 20S catalytic core of the 26S proteasome has the shape of a barrel made of four rings which are composed of seven differentαsubunitsα_1-α_7 at two outer rings and seven differentβsubunitsβ_1-β_7 at two inner rings at which the catalytic sites locate. Three of theβsubunits contain proteolyses sites, which are sequestered in the hollow interior of the 20S particle. Substrates enter the 20S through a narrow channel formed by theβsubunits, whose N-termini, depending on their conformation, can either obstruct or allow substrate entry and thus function as a gate. This entry channel is narrow and only permits passage of unfolded, linearized polypeptides.

哺乳动物26S蛋白酶体是由一个20S催化颗粒(catalytic particle，CP)和两个19S调节颗粒(regulatory particle，RP)组成的ATP(adenosine-triphosphate，ATP)依赖性蛋白水解酶复合体。20S CP是26S蛋白酶体的催化核心，它是由4个圆环堆叠形成的桶状复合物，其中两侧外环每个环是由α_1-α_7亚基组成，两个内环每个环是由β_1-β_7亚基组成，4个环的中央形成一个狭窄的内腔。2个β内环形成了20S CP的催化中心空腔，其内壁为催化活性位点所在地；外侧α环中心的孔道是底物到达催化中心空腔的通道，一般被α亚基上的N末端所封闭，阻止胞内非目的靶蛋白进入20S CP内被降解破坏。

Means the parent directory, so this command means to execute "toolchain.sh," which is in the current directory.

代表父目录，所以这个命令就是执行当前目录下的"toolchain.sh"。

Yes,In fact,I'm on our city ream.

是的。事实上我是我们市队的。