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. 1976 Mar 1;68(3):420–429. doi: 10.1083/jcb.68.3.420

Microplicae: characteristic ridge-like folds of the plasmalemma

PMCID: PMC2109650  PMID: 828906

Abstract

Scanning electron microscopy reveals that the free surfaces of stratified squamous epithelial cells lining the alimentary tract, cornea, and conjunctiva exhibit characteristic ridge-like folds of plasmalemma. These microplicae are approximately 0.1-0.2 micronm in width, of variable height (0.2-0.8 micronm) and length, may followstraight or winding paths, often branch, and exhibit a wide variety of patterns over the surfaces of cells. Transmission electron microscopy reveals that microplicae often have a fine (100-150 A) electron-dense zone subjacent to their plasmalemma and an intracellular matrix characterized by a disorderly arrary of fine filaments (40-60 A in diameter). Microplicae appear to arise from plasmalemmal fold which once provided for intercellular interdigitation and desmosome abhesion between adjacent cells. Ruthenium red staining demonstrates that microplicae and interplical grooves are covered with a polyanionic glycocalyx. Although free surface microplicae may merely represent the renmants of intercellular interdigitations or a modified expression of microvillous-like extensions, it is also possible that they serve another specific function. In this regard it is speculated that microplical and interplical grooves may function to hold a layer of lubricating and cushioning mucin designed to protect the underlying plasmalemma from abrasive abuse.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Andrews P. M., Hackenbrock C. R. A scanning and stereographic ultrastructural analysis of the isolated inner mitochondrial membrane during change in metabolic activity. Exp Cell Res. 1975 Jan;90(1):127–136. doi: 10.1016/0014-4827(75)90365-1. [DOI] [PubMed] [Google Scholar]
  2. Andrews P. M., Porter K. R. A scanning electron microscopic study of the nephron. Am J Anat. 1974 May;140(1):81–115. doi: 10.1002/aja.1001400107. [DOI] [PubMed] [Google Scholar]
  3. Davis W. L., Goodman D. B., Martin J. H., Matthews J. L., Rasmussen H. Vasopressin-induced changes in the toad urinary bladder epithelial surface. J Cell Biol. 1974 May;61(2):544–547. doi: 10.1083/jcb.61.2.544. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Ito S. The enteric surface coat on cat intestinal microvilli. J Cell Biol. 1965 Dec;27(3):475–491. doi: 10.1083/jcb.27.3.475. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Luft J. H. Ruthenium red and violet. I. Chemistry, purification, methods of use for electron microscopy and mechanism of action. Anat Rec. 1971 Nov;171(3):347–368. doi: 10.1002/ar.1091710302. [DOI] [PubMed] [Google Scholar]
  6. Pfister R. R. The normal surface of corneal epithelium: a scanning electron microscopic study. Invest Ophthalmol. 1973 Sep;12(9):654–668. [PubMed] [Google Scholar]
  7. Price Z. H. A three-dimensional model of membrane ruffling from transmission and scanning electron microscopy of cultured monkey kidney cells (LLCMK 2 ). J Microsc. 1972 Jun;95(3):493–505. doi: 10.1111/j.1365-2818.1972.tb01053.x. [DOI] [PubMed] [Google Scholar]
  8. REYNOLDS E. S. The use of lead citrate at high pH as an electron-opaque stain in electron microscopy. J Cell Biol. 1963 Apr;17:208–212. doi: 10.1083/jcb.17.1.208. [DOI] [PMC free article] [PubMed] [Google Scholar]

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