发信人: space (排骨教主), 信区: Biology
标 题: Re: SBIG: Channels
发信站: Unknown Space - 未名空间 (Thu Oct 16 21:44:22 2003), 转信

我看了那个图象,通道不对称. cavity在靠近细胞内的一面. 所以我才问方向的
问题. 可如果这完全是单向的,那么最终细胞内K+浓度会减少到很低的水平. 必须
有反向的流动才能维持平衡.

另外,细胞内K+浓度比外面高了30倍.这是靠什么维持的呢?



【 在 doggiebear (doggiebear) 的大作中提到: 】
: The directinality of the channel is a good question.
: I do not know. (though I can search for answer)
: I say it is imporant becasue it verify the role of the helix term and the
: cavity. Based on this principle, I will say the channel should have
: directionality. That means, ion can only come out from the cell, not the
: opposite, or the stabilization effect will not be there.
: I bet ppl has done experiment on it. This is kind of classical
: electriphysiology research.
: I think dehydration is the the critical step for ion selection. The selective
: filter is small enough to for only dehydrated ion. Therefore, when an hydrated
: ion comes in, it is recognized by charged groups on the selective filter and
: tranfered from water molecules to the interation partners of the filter and
: start the transfering process.
: 【 在 space (排骨教主) 的大作中提到: 】
: : 我这几天脖子给拧了,没好好看文章. 今天在医院把K+ channel匆匆看了一下,很不得
: : 要领,和我缺乏生物知识有关系.首先我就没搞清楚K+ channel是不是双向的, 其次
: : 我也没搞清楚hydration和dehydration在这里面的角色是什么, 最后我也不清楚
: : 这channel尺寸(宽度和高度)怎么样. 我先看看你们的讨论学习学习吧.
: from
: charges
: field
: The
: cavity.
: energy
: membrane
: C-term
: cavity.
: axial
: happens.
: shows,
: is
: job,


--
乌鸦大兄.

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