Midgut GPI-anchored proteins with alkaline phosphatase activity from the cotton boll weevil (Anthonomus grandis) are putative receptors for the Cry1B protein of Bacillus thuringiensis.
Cry toxins from Bacillus thuringiensis (Bt) are used for insect control. They interact with specific receptors located on the host cell surface and are activated by host proteases following receptor binding resulting in midgut epithelial cells lysis. In this work we had cloned, sequenced and expressed a cry1Ba toxin gene from the B thuringiensis S601 strain which was previously shown to be toxic to Anthonomus grandis, a cotton pest. The Cry1Ba6 protein expressed in an acrystaliferous B. thuringiensis strain was toxic to A. grandis in bioassays. The binding of Cry1Ba6 toxin to proteins located in the midgut brush border membrane of A. grandis was analyzed and we found that Cry1Ba6 binds to two proteins (62 and 65kDa) that showed alkaline phosphatase (ALP) activity. This work is the first report that shows the localization of Cry toxin receptors in the midgut cells of A. grandis.
Martins
Erica Soares
ES
Universidade de Brasília, Departamento de Biologia Celular, Brasília, DF, Brazil.
Monnerat
Rose Gomes
RG
Queiroz
Paulo Roberto
PR
Dumas
Vinicius Fiuza
VF
Braz
Shélida Vasconcelos
SV
de Souza Aguiar
Raimundo Wagner
RW
Gomes
Ana Cristina Menezes Mendes
AC
Sánchez
Jorge
J
Bravo
Alejandra
A
Ribeiro
Bergmann Morais
BM
D000469:Alkaline Phosphatase / Q000378:metabolism*; D000818:Animals; D001413:Bacillus thuringiensis / Q000378:metabolism*; D001427:Bacterial Toxins / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D001517:Coleoptera / Q000201:enzymology*; D004591:Electrophoresis, Polyacrylamide Gel; D017261:Glycosylphosphatidylinositols / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism
D001427:Bacterial Toxins; D017261:Glycosylphosphatidylinositols; D011994:Recombinant Proteins; D000469:Alkaline Phosphatase