发信人: doggiebear (doggiebear), 信区: Biology
标 题: SBIG: Channels - 2
发信站: Unknown Space - 未名空间 (Fri Oct 17 00:19:26 2003) WWW-POST

http://www.hhmi.org/research/investigators/images/mackinnon_fig1_lg.gif

This is the major figure from Mackinon's classical potassium channel work.
Now it is the trademark of the potassium channel. It will be remembered by
generations of biologists, like watson's double helix image.

But what does it mean?

Look at the left figure.

It reveals the dehyration, transport and rehydration process of the whole
event. The bottom cavity is within the cell. It is water filled and supposed
to overcome membrane repulsion force against the ion. You can see the ion is
well positioned in the center of the cavity, surrounded by water molecules.
The narrow channel is the selective filter. You can see the naked
ion barely pass through it. you can see four ions. But this is not the true
image. Actually, it is the average of two configurations, each of which has
two ion and two water molecules within the selective filter.
After getting out of the filter, the ions are re-hydrated.





--
I will vote a democrat even he is a dog.
Liberalism is something to be proud of!
※ 修改:·doggiebear 於 Oct 17 00:19:26 修改本文·[FROM: 208.180.]
※ 来源:．Unknown Space - 未名空间 mitbbs.com．[FROM: 208.180.]