PMID: 10309Oct 1, 1976

The microsporidian spore invasion tube. The ultrastructure, isolation, and characterization of the protein comprising the tube

The Journal of Cell Biology
E Weidner


The extrusion apparatus of the microsporidian parasitic protozoan Nosema michaelis discharges an invasion (or polar) tube with a velocity suitalbe for piercing cells and injecting infective sporoplasm. The tube is composed of a polar tube protein (PTP) which consists of a single, low molecular weight polypeptide slightly smaller than chymotrypsinogen-A. Assembled PTP tubes resist dissociation in sodium dodecyl sulfate and brief exposures in media at extreme ends of the pH range; however, the tubes are reduced by mercaptoethanol and dithiothreitol. When acidified, mercaptoethanol-reduced PTP self-assembles into plastic, two-dimensional monolayers. Dithiothreitol-reduced PTP will not reassemble when acidified. Evidence is presented which indicates that PTP is assembled as a tube within the spore; that the ejected tube has plasticity during sporoplasm passage; and, finally, that the subunits within the tube polymer are bound together, in part, by interprotein disulfide linkages.


Feb 1, 1975·The Journal of protozoology·A H Undeen
Feb 1, 1975·The Journal of Cell Biology·D Alder, M A Gorovsky
May 1, 1973·Proceedings of the National Academy of Sciences of the United States of America·G C KooM P Lardis
Nov 14, 1971·Journal of Molecular Biology·L P Everhart
Apr 1, 1964·Biochemistry·W W CLELAND


Jun 18, 2010·Parasitology Research·Boumediene Bouzahzah, Louis M Weiss
Aug 1, 1996·Molecular and Biochemical Parasitology·E M KeohaneLouis M Weiss
Jun 22, 2002·Molecular and Biochemical Parasitology·I PeuvelF Delbac
Jun 1, 1982·The Journal of Cell Biology·E Weidner
May 9, 2006·Antioxidants & Redox Signaling·Donald L Coppock, Colin Thorpe
Aug 11, 1993·Nucleic Acids Research·X ZhuLouis M Weiss
May 1, 1996·The Journal of Eukaryotic Microbiology·S K HalonenJ F Siebenaller
Jan 1, 1996·The Journal of Eukaryotic Microbiology·E M KeohaneLouis M Weiss
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Apr 3, 1999·The Journal of Eukaryotic Microbiology·E M KeohaneLouis M Weiss
Sep 16, 1999·Journal of Invertebrate Pathology·J R FuxaL R LaMotte
Jan 1, 1992·Critical Reviews in Microbiology·V SpragueE I Hazard
Jul 12, 2005·International Journal for Parasitology·Yanji Xu, Louis M Weiss
Mar 7, 2001·Acta Tropica·Louis M Weiss
Jul 24, 2019·The Journal of Eukaryotic Microbiology·Peter M TakvorianLouis M Weiss
Oct 20, 2018·Expert Opinion on Therapeutic Targets·Bing Han, Louis M Weiss
Nov 18, 2018·Current Protocols in Microbiology·Bing HanLouis M Weiss
Mar 6, 2020·Frontiers in Microbiology·Bing HanLouis M Weiss
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