Atomic force microscopy and dissection of gap junctions.

J H Hoh; R Lal; S A John; J P Revel; M F Arnsdorf

doi:10.1126/science.1910206

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PubMed · 1910206

Atomic force microscopy and dissection of gap junctions.

J H Hoh·R Lal·S A John·J P Revel·M F Arnsdorf

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Abstract

An atomic force microscope (AFM) was used to study the structure of isolated hepatic gap junctions in phosphate-buffered saline (PBS). The thickness of these gap junctions appears to be 14.4 nanometers, close to the dimensions reported by electron microscopy (EM). When an increasing force is applied to the microscope tip, the top membrane of the gap junction can be "dissected" away, leaving the extracellular domains of the bottom membrane exposed. When such "force dissection" is performed on samples both trypsinized and fixed with glutaraldehyde, the hexagonal array of gap junction hemichannels is revealed, with a center-to-center spacing of 9.1 nanometers.

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Animals Fourier Analysis Glutaral Intercellular Junctions Liver Microscopy Microscopy, Electron Rats Trypsin Comparative Study Journal Article Research Support, U.S. Gov't, P.H.S.

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J H Hoh, R Lal, S A John, J P Revel, M F Arnsdorf. 1991-09-20. Atomic force microscopy and dissection of gap junctions.. https://doi.org/10.1126/science.1910206

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