Tribolium castaneum Apolipophorin-III acts as an immune response protein against Bacillus thuringiensis Cry3Ba toxic activity

J Invertebr Pathol. 2013 Jul;113(3):209-13. doi: 10.1016/j.jip.2013.04.002. Epub 2013 Apr 18.

Abstract

In this study, a 2.1-fold Apolipophorin-III mRNA up-regulation was found in Tribolium castaneum larvae challenged with Bacillus thuringiensis Cry3Ba spore-crystal mixture. Knockdown of Apolipophorin-III by RNAi resulted in increased T. castaneum larvae susceptibility following Cry3Ba spore-crystal treatment, demonstrating Apolipophorin-III involvement in insect defense against B. thuringiensis. We showed that Apolipophorin-III participates in T. castaneum immune response to B. thuringiensis activating the prophenoloxidase cascade since: (i) phenoloxidase activity significantly increased after Cry3Ba spore-crystal treatment compared to untreated or Cry1Ac spore-crystal treated larvae and (ii) phenoloxidase activity in Cry3Ba spore-crystal treated Apolipophorin-III silenced larvae was 71±14% lower than that of non-silenced intoxicated larvae.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apolipoproteins / antagonists & inhibitors
  • Apolipoproteins / genetics
  • Apolipoproteins / physiology*
  • Bacillus thuringiensis / immunology
  • Bacillus thuringiensis Toxins
  • Bacterial Proteins*
  • Endotoxins*
  • Hemolysin Proteins*
  • Immunity, Innate
  • Insecticides*
  • Larva / genetics
  • Larva / immunology
  • Larva / microbiology
  • RNA Interference
  • Toxicity Tests
  • Tribolium / genetics
  • Tribolium / immunology*
  • Tribolium / microbiology

Substances

  • Apolipoproteins
  • Bacillus thuringiensis Toxins
  • Bacterial Proteins
  • Endotoxins
  • Hemolysin Proteins
  • Insecticides
  • apolipophorin III
  • insecticidal crystal protein, Bacillus Thuringiensis