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NASA NTRS · 20040087762

The endomembrane requirement for cell surface repair

McNeil, Paul L.·Miyake, Katsuya·Vogel, Steven S.
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Abstract

The capacity to reseal a plasma membrane disruption rapidly is required for cell survival in many physiological environments. Intracellular membrane (endomembrane) is thought to play a central role in the rapid resealing response. We here directly compare the resealing response of a cell that lacks endomembrane, the red blood cell, with that of several nucleated cells possessing an abundant endomembrane compartment. RBC membrane disruptions inflicted by a mode-locked Ti:sapphire laser, even those initially smaller than hemoglobin, failed to reseal rapidly. By contrast, much larger laser-induced disruptions made in sea urchin eggs, fibroblasts, and neurons exhibited rapid, Ca(2+)-dependent resealing. We conclude that rapid resealing is not mediated by simple physiochemical mechanisms; endomembrane is required.

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NASA Discipline Cell BiologyNon-NASA CenterCell Membrane/physiologyIntracellular Membranes/physiologyFluorescent DyesFibroblasts/cytology/physiologyStress, MechanicalOocytes/cytology/physiologyCalcium/metabolismMicroscopy, ElectronErythrocytes/cytology/physiologyIn VitroCell Survival/physiologyFemaleAnimalsCell Membrane PermeabilityOsmotic PressureSupport, U.S. Gov't, Non-P.H.SSea UrchinsPyridinium CompoundsSupport, U.S. Gov't, P.H.SRatsAmmonium CompoundsNeurons/cytology/physiology

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McNeil, Paul L., Miyake, Katsuya, Vogel, Steven S.. 2003-04-15. The endomembrane requirement for cell surface repair. https://ntrs.nasa.gov/citations/20040087762

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