Porocytosis: secretion from small and medium-diameter vesicles and vesicle arrays without membrane fusion.
Porocytosis: secretion from small and medium-diameter vesicles and vesicle arrays without membrane fusion.
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孔细胞增多症：中小直径囊泡和囊泡阵列的分泌，无膜融合。
DOI：
10.1023/b:neur.0000010086.07636.df
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发表时间：
2003
期刊：
影响因子：
--
通讯作者：
Pappas,GeorgeD
中科院分区：
文献类型：
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作者：
Silver,RobertB;Kriebel,MahlonE;Keller,Bruce;Pappas,GeorgeD
我们最近提出了一种机制来描述分泌，这是所有细胞的基本过程。这个假说被称为胞浆细胞增多症，它包含了所有可用的数据，并包括两种形式的分泌，即，泡状和结构性的。目前公认的胞吐分泌涉及囊泡和质膜的物理融合。然而，该假设的机制并不适合所有可用的生理数据（Silveret等人，2001; Kriebelet等人，2001年）。并置的脂质双层的能量学不支持非易化融合。钙离子水平在微区中以10 - 4-10 - 3 M的水平升高1 ms或更短，其中钙离子在分泌位点显示出有限的侧向移动性（Llinaset al.，1992年，Silveret等人，1994年）。我们认为，钙离子，其流动性在空间和时间上受到限制，建立相邻的脂质分子之间的“盐桥”，并建立跨越囊泡和质膜脂质双层的瞬时孔;该瞬时孔的寿命完全取决于足够的钙离子水平的持续时间。
We have recently proposed a mechanism to describe secretion, a fundament process in all cells. That hypothesis, calledporocytosis, embodies all available data, and encompasses both forms of secretion,i.e., vesicular and constitutive. The current accepted view of exocytotic secretion involves the physical fusion of vesicle- and plasma membranes. However, that hypothesized mechanism does not fit all available physiological data (Silveret al., 2001; Kriebelet al., 2001). Energetics of apposed lipid bilayers do not favor unfacilitated fusion. Calcium ion levels are elevated in microdomains at levels of 10−4–10−3M for 1 ms or less, with the calcium ions showing limited lateral mobility at the site of secretion (Llinaset al., 1992, Silveret al., 1994). We consider that calcium ions, whose mobility is restricted in space and time, establish “salt-bridges” among adjacent lipid molecules, and establishes transient pores that span the vesicle and plasma membrane lipid bilayers; the lifetime of that transient pore being completely dependent on duration of sufficient calcium ion levels.