title: Analyses of α-amylase and α-glucosidase in the malaria vector mosquito, Anopheles gambiae, as receptors of Cry11Ba toxin of Bacillus thuringiensis subsp. jegathesan.
abstract: Bacillus thuringiensis subsp. jegathesan produces Cry11Ba crystal protein with high toxicity to mosquito larvae. The Cry11Ba toxicity is dependent on its receptors on mosquito larval midgut epithelial cells. Previously, a cadherin-like protein (AgCad2), aminopeptidase (AgAPN2) and alkaline phosphatase (AgALP1) were reported to be involved in regulation of Cry11Ba toxicity on Anopheles gambiae larvae. Here, the cDNAs encoding α-amylase (AgAmy1) and α-glucosidase (Agm3) were cloned from A. gambiae larva midgut. Both are glycophosphatidylinositol (GPI) anchored proteins on brush border membranes (BBMV). Immunohistochemistry revealed their localization on different regions of the larval midgut. AgAmy1 and Agm3 bound Cry11Ba with high affinity, 37.6 nM and 21.1 nM respectively. Cry11Ba toxicity against A. gambiae larvae was neutralized by both AgAmy1 and Agm3. The results provide evidence that both AgAmy1 and Agm3 function as receptors of Cry11Ba in A. gambiae.
authors.affiliation: Department of Entomology, University of Georgia, Athens, GA 30602-2603, USA.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.forename: Gang
authors.initials: G
authors.lastname: Hua
authors.forename: Krishnareddy
authors.initials: K
authors.lastname: Bayyareddy
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Adang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000852:Anopheles / Q000187:drug effects / Q000201:enzymology*; D000918:Antibody Specificity; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000378:metabolism* / Q000633:toxicity; D004731:Endotoxins / Q000378:metabolism* / Q000633:toxicity; D006460:Hemolysin Proteins / Q000378:metabolism* / Q000633:toxicity; D007303:Insect Vectors / Q000201:enzymology; D007814:Larva / Q000201:enzymology; D008288:Malaria / Q000201:enzymology / Q000635:transmission; D008871:Microvilli / Q000201:enzymology; D008969:Molecular Sequence Data; D000516:alpha-Amylases / Q000378:metabolism*; D000520:alpha-Glucosidases / Q000378:metabolism*
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis; D000516:alpha-Amylases; D000520:alpha-Glucosidases
keywords: Agm3; Amyl; Amylase; Anopheles gambiae glucosidase; BBMV; BSA; Bacillus thuringiensis; Bt; CRD; Cry toxin; Glucosidase; Mosquitocidal; PCR; PMF; amylase; bovine serum albumin; brush border membrane vesicles; cross-reacting determinant; peptide mass fingerprinting; polymerase chain reaction