Possible role of calmodulin in the secretion of Entamoeba histolytica electron‐dense granules containing collagenase

Entamoeba histolytica cells secrete electron‐dense granules (EDGs) that have collagenase activity. To study the possible involvement of calmodulin (CaM) on EDG secretion, the effect of several CaM antagonists (TFP, R24571, W‐7, W‐5, dibucaine and DL‐propranolol) was tested on this cellular function. Except for W‐5 and dibucaine, the rest of these compounds inhibited EDG secretion. Transmission electron microscopy of collagen‐activated trophozoites showed numerous EDGs located in or near the surface membrane. In contrast, trophozoites incubated with TFP showed no EDGs. Protein kinase C inhibitors (H‐7, ML‐9) had no effect on EDG secretion, suggesting that CaM antagonists acted by selectively inhibiting CaM. These results suggest that a CaM‐dependent process is involved in EDG secretion.

[1]  R. Tovar,et al.  Antigens in electron-dense granules from Entamoeba histolytica as possible markers for pathogenicity , 1990, Journal of clinical microbiology.

[2]  C. Atkinson,et al.  Calcium and calmodulin antagonists inhibit human malaria parasites (Plasmodium falciparum): implications for drug design. , 1987, Proceedings of the National Academy of Sciences of the United States of America.

[3]  S. Wieder,et al.  Giardia lamblia: detection and characterization of calmodulin. , 1987, Experimental parasitology.

[4]  A. Martínez-Palomo,et al.  Entamoeba Histolytica : Activation and Release of Membrane Dense Bodies , 1987 .

[5]  H. Hidaka,et al.  Effect of calmodulin inhibitors on thyroid hormone secretion. , 1986, Endocrinology.

[6]  J. McKerrow,et al.  The major neutral proteinase of Entamoeba histolytica , 1986, The Journal of experimental medicine.

[7]  R. Delorenzo.  Calcium and Calmodulin Control of Neurotransmitter Synthesis and Release , 1985 .

[8]  P. Peachell,et al.  Calcium Regulation of Histamine Secretion from Mast Cells , 1985 .

[9]  A. Martínez-Palomo,et al.  Entamoeba histolytica: collagenolytic activity and virulence. , 1984, The Journal of protozoology.

[10]  H. Hidaka,et al.  Two types of calmodulin antagonists: a structurally related interaction. , 1984, Pharmacology.

[11]  J. Kuo,et al.  Modes of inhibition by acylcarnitines, adriamycin and trifluoperazine of cardiac phospholipid-sensitive calcium-dependent protein kinase. , 1983, Biochemical pharmacology.

[12]  R. Garofalo,et al.  Calmodulin antagonists inhibit secretion in Paramecium , 1983, The Journal of cell biology.

[13]  E. Kessler,et al.  Correlation of Virulence and Collagenolytic Activity in Entamoeba histolytica , 1983, Infection and immunity.

[14]  R. Schatzman,et al.  N-(6-Aminohexyl)-5-chloro-1-naphthalenesulfonamide(W-7), a calmodulin antagonist, also inhibits phospholipid-sensitive calcium-dependent protein kinase. , 1983, Biochimica et biophysica acta.

[15]  B. Weiss,et al.  Interaction of drugs with calmodulin. Biochemical, pharmacological and clinical implications. , 1982, Biochemical pharmacology.

[16]  W. Anderson,et al.  Ca2+-induced hydrophobic site on calmodulin: application for purification of calmodulin by phenyl-Sepharose affinity chromatography. , 1982, Biochemical and biophysical research communications.

[17]  M. L. Muñoz,et al.  The collagenase of Entamoeba histolytica , 1982, The Journal of experimental medicine.

[18]  H. Hidaka,et al.  Activity-structure relationship of calmodulin antagonists, Naphthalenesulfonamide derivatives. , 1981, Molecular pharmacology.

[19]  L. V. Van Eldik,et al.  Reproducible production of antiserum against vertebrate calmodulin and determination of the immunoreactive site. , 1981, The Journal of biological chemistry.

[20]  H. Hidaka,et al.  Ca2+ -calmodulin-dependent phosphorylation and platelet secretion , 1980, Nature.

[21]  Y. Nishizuka,et al.  Inhibitory action of chlorpromazine, dibucaine, and other phospholipid-interacting drugs on calcium-activated, phospholipid-dependent protein kinase. , 1980, The Journal of biological chemistry.

[22]  A. Means,et al.  Calmodulin—an intracellular calcium receptor , 1980, Nature.

[23]  B. Johnson-Wint,et al.  A quantitative collagen film collagenase assay for large numbers of samples. , 1980, Analytical biochemistry.

[24]  W. Y. Cheung,et al.  Calmodulin plays a pivotal role in cellular regulation. , 1980, Science.

[25]  H. Towbin,et al.  Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. , 1979, Proceedings of the National Academy of Sciences of the United States of America.

[26]  L S Diamond,et al.  A new medium for the axenic cultivation of Entamoeba histolytica and other Entamoeba. , 1978, Transactions of the Royal Society of Tropical Medicine and Hygiene.

[27]  M. M. Bradford.  A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. , 1976, Analytical biochemistry.

[28]  J. H. Wang,et al.  Mechanism of activation of a cyclic adenosine 3':5'-monophosphate phosphodiesterase from bovine heart by calcium ions. Identification of the protein activator as a Ca2+ binding protein. , 1973, The Journal of biological chemistry.

[29]  U. K. Laemmli,et al.  Cleavage of Structural Proteins during the Assembly of the Head of Bacteriophage T4 , 1970, Nature.

[30]  F. Lipmann,et al.  A colorimetric determination of inorganic pyrophosphate. , 1954, The Journal of biological chemistry.