Expression of Hsp90, Hsp70 and Hsp60 inTrichinellaspecies exposed to oxidative shock

Abstract

AbstractStress response and phosphorylation of heat shock proteins (HSPs) 60, 70 and 90 were studied inTrichinella nativa,T. nelsoni,T. pseudospiralisandT. spiralislarvae at 30-min intervals following exposure to 20, 100 and 200 mM H2O2. There was a time- and dose-dependent differential survival for the infective stage larvae (L1) of these fourTrichinellaspecies. Immunoblotting analysis revealed that constitutive Hsp60 and Hsp70, but not Hsp90, from testTrichinellaspecies are constitutively phosphorylated on serine/threonine residues as they converted to forms with increased sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE) mobility by treatment with alkaline phosphatase. After exposure to H2O2, while there was a time-related occurrence of the three HSPs with decreased SDS–PAGE mobility, these HSPs were insensitive to alkaline phosphatase except in the case of exposure to 20 mM H2O2for Hsp60 from allTrichinellaspecies and Hsp70 fromT. spiralisandT. nelsoni. The synthesis of HSPs forms with decreased SDS–PAGE mobility is a susceptibility signal because the lower concentration of peroxide (20 mM) did not cause a decrease on HSPs SDS–PAGE mobility inT. spiralisandT. nelsoni, the two more resistant selectedTrichinellaspecies.