Massive endocytosis driven by lipidic forces originating in the outer plasmalemmal monolayer: a new approach to membrane recycling and lipid domains.
Massive endocytosis driven by lipidic forces originating in the outer plasmalemmal monolayer: a new approach to membrane recycling and lipid domains.
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由脂质力驱动的大量内吞作用，该脂质力源自外部浆膜单层：一种新的膜回收和脂质结构域的方法。
DOI：
10.1085/jgp.201010469
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发表时间：
2011-02
期刊：
影响因子：
--
通讯作者：
Hilgemann DW
中科院分区：
文献类型：
--
作者：
Fine M;Llaguno MC;Lariccia V;Lin MJ;Yaradanakul A;Hilgemann DW
脂类在内吞作用中所起的作用是争论的主题。我们用电学和成像的方法，描述了当非离子去污剂Triton X-100(TX100)和NP-40干扰外质膜单层时，新生仓鼠肾(BHK)和HEK293细胞的大量内吞(MEND)。一些烷烃洗涤剂、两亲性药物艾德福辛和他莫昔芬以及磷脂酶抑制剂U73122也有效。膜示踪剂FM4-被囊泡摄取和可逆FM4-结合的丧失证实了40%-75%的细胞表面被内化。正在进行的修复在2-4 S中停止，当双路被移除时，从胞质侧看，双路不起作用。因此，外层单层的膨胀是至关重要的。对于钙激活的修复，形成的囊泡直径为100 nm，膜皱纹消失，β-环糊精处理具有抑制作用。然而，安非他命激活的MEND不需要钙瞬变、三磷酸腺苷(ATP)水解、G蛋白循环、动力素或肌动蛋白细胞骨架重构。随着细胞质中ATP浓度的升高，MEND可以完全逆转，并在BHK和HEK293细胞中重复多次，但不能在心肌细胞中重复。逆转可被N-乙基马来酰亚胺和一氧化氮供体硝普钠阻断。成分性表达的Na/Ca交换器内化大致与表面膜成比例，而Na/K泵活性则过度降低。十二烷基硫酸钠和十二烷基葡萄糖苷在使用过程中不会引起修复，但当它们被移除时，修复会迅速发生。根据电容监测，这些洗涤剂的结合量随着Mend的增加而减少，而TX100的结合量不会减少。综上所述，非离子洗涤剂可以在体内分离质膜，形成的囊泡立即连接到生理膜转运机制。我们认为，质膜的横向和跨双层不均一性提供了潜在的能量，当不受触发因素的限制时，可以通过脂类力量驱动内吞作用。
The roles that lipids play in endocytosis are the subject of debate. Using electrical and imaging methods, we describe massive endocytosis (MEND) in baby hamster kidney (BHK) and HEK293 cells when the outer plasma membrane monolayer is perturbed by the nonionic detergents, Triton X-100 (TX100) and NP-40. Some alkane detergents, the amphipathic drugs, edelfosine and tamoxifen, and the phospholipase inhibitor, U73122, are also effective. Uptake of the membrane tracer, FM 4–64, into vesicles and loss of reversible FM 4–64 binding confirm that 40–75% of the cell surface is internalized. Ongoing MEND stops in 2–4 s when amphipaths are removed, and amphipaths are without effect from the cytoplasmic side. Thus, expansion of the outer monolayer is critical. As found for Ca-activated MEND, vesicles formed are <100 nm in diameter, membrane ruffles are lost, and β-cyclodextrin treatments are inhibitory. However, amphipath-activated MEND does not require Ca transients, adenosine triphosphate (ATP) hydrolysis, G protein cycling, dynamins, or actin cytoskeleton remodeling. With elevated cytoplasmic ATP (>5 mM), MEND can reverse completely and be repeated multiple times in BHK and HEK293 cells, but not cardiac myocytes. Reversal is blocked by N-ethylmaleimide and a nitric oxide donor, nitroprusside. Constitutively expressed Na/Ca exchangers internalize roughly in proportion to surface membrane, whereas Na/K pump activities decrease over-proportionally. Sodium dodecyl sulfate and dodecylglucoside do not cause MEND during their application, but MEND occurs rapidly when they are removed. As monitored capacitively, the binding of these detergents decreases with MEND, whereas TX100 binding does not decrease. In summary, nonionic detergents can fractionate the plasma membrane in vivo, and vesicles formed connect immediately to physiological membrane-trafficking mechanisms. We suggest that lateral and transbilayer inhomogeneities of the plasma membrane provide potential energies that, when unbridled by triggers, can drive endocytosis by lipidic forces.
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影响因子：
4.8
作者：
Donaldson, Julie G.;Porat-Shliom, Natalie;Cohen, Lee Ann
通讯作者：
Cohen, Lee Ann
影响因子：
4.8
作者：
Garcia-Saez, Ana J.;Chiantia, Salvatore;Schwille, Petra
通讯作者：
Schwille, Petra
影响因子：
64.8
作者：
Matheny, SA;Chen, CY;White, MA
通讯作者：
White, MA
DOI：
10.1073/pnas.92.24.11220
发表时间：
1995-11-21
影响因子：
11.1
作者：
LU, CC;KABAKOV, A;HILGEMANN, DW
通讯作者：
HILGEMANN, DW
影响因子：
3.4
作者：
Sarasij, R. C.;Mayor, Satyajit;Rao, Madan
通讯作者：
Rao, Madan