Ribonuclease-gold labels proteoglycan-containing cytoplasmic granules and ribonucleic acid-containing organelles - A survey

• Dvorak, A. M. ^[1] ; Morgan, E.S. ^[1]
  1. [1] Departments of Pathology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
• Localización: Histology and histopathology: cellular and molecular biology, ISSN-e 1699-5848, ISSN 0213-3911, Vol. 14, Nº. 2, 1999, págs. 597-626
• Idioma: inglés
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• Resumen

  • An enzyme-affinity-gold method to detect RNA in routinely prepared ultrastructural samples is based on the affinity of the gold-coupled enzyme, ribonuclease, for its substrate, RNA. High concentrations of a known inhibitor of RNase , heparin, are uniquely located in human mast cell granules. Specific labeling for the presence of heparin in these structures was determined using the RNase-gold (R-G) reagent based on the RNase inhibitor property of heparin. This property was used to probe for the presence of proteoglycans (PG) known to be present in a wide variety of ultrastructural samples, none of which contain heparin.

    In addition to known subcellular sites of RNA, the R-G re age nt was shown to bind to PG-rich cytoplasmic granules in a wide variety of leukocytes and secretory cells of epithelial, endocrine, and neuroendocrine origin.

    This newly recognized property was used to image the changing distribution of labeled PGs during cellular maturation , secretion, and recovery from secretion of secretory cells in vivo, ex vivo, in vitro and in isolated, biochemically defined guinea pig basophil granule preparations.