Identification of midgut membrane proteins from different instars of Helicoverpa armigera (Lepidoptera: Noctuidae) that bind to Cry1Ac toxin
Por:
Sena Da Silva, Igor Henrique, Gomez, Isabel, Sanchez, Jorge, Martinez de Castro, Diana L., Valicente, Fernando Hercos, Soberon, Mario, Polanczyk, Ricardo Antonio, Bravo, Alejandra
Publicada:
6 dic 2018
Resumen:
Helicoverpa armigera is a polyphagous pest sensitive to Cry1Ac protein
from Bacillus thuringiensis (Bt). The susceptibility of the different
larval instars of H. armigera to Cry1Ac protoxin showed a significant
45-fold reduction in late instars compared to early instars. A possible
hypothesis is that gut surface proteins that bind to Cry1Ac differ in
both instars, although higher Cry toxin degradation in late instars
could also explain the observed differences in susceptibility. Here we
compared the Cry1Ac-binding proteins from second and fifth instars by
pull-down assays and liquid chromatography coupled to mass spectrometry
analysis (LC-MS/MS). The data show differential protein interaction
patterns of Cry1Ac in the two instars analyzed. Alkaline phosphatase,
and other membrane proteins, such as prohibitin and an anion selective
channel protein were identified only in the second instar, suggesting
that these proteins may be involved in the higher toxicity of Cry1Ac in
early instars of H. armigera. Eleven Cry1Ac binindg proteins were
identified exclusively in late instar larvae, like different proteases
such as trypsin-like protease, azurocidin-like proteinase, and
carboxypeptidase. Different aminopeptidase N isofroms were identified in
both instar larvae. We compared the Cry1Ac protoxin degradation using
midgut juice from late and early instars, showing that the midgut juice
from late instars is more efficient to degrade Cry1Ac protoxin than that
of early instars, suggesting that increased proteolytic activity on the
toxin could also explain the low Cry1Ac toxicity in late instars.
Filiaciones:
Sena Da Silva, Igor Henrique:
Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Fitossanidade, Jaboticabal, SP, Brazil
Gomez, Isabel:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
Sanchez, Jorge:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
Martinez de Castro, Diana L.:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
Valicente, Fernando Hercos:
Embrapa Milho & Sorgo, Sete Lagoas, MG, Brazil
Soberon, Mario:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
Polanczyk, Ricardo Antonio:
Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Fitossanidade, Jaboticabal, SP, Brazil
Bravo, Alejandra:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
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