Cholera toxin: Difference between revisions
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== Function == | == Function == | ||
Cholera toxin, after being secreted from the ''Vibrio cholerae'', binds to the enterocytes (intestinal cells) by the interaction between the subunit B and GM1 ganglioside[http://en.wikipedia.org/wiki/GM1] receptor on enterocytes, which then promotes the toxin endocytosis. Next, A1 turns to an active enzyme after separating with the A2 domain. After the A1 domain of subunit A of the toxin enters the cytosol, it activates adenylate cyclase to produce cAMP through G proteins, which triggers the activation of cystic fibrosis transmembrane conductance regulator (CFTR), leading to watery diarrhea: the efflux of water and ions from cells <ref>Jennifer McDowall, Cholera Toxin, EMBL-EMI, Interpro</ref>. | Cholera toxin, after being secreted from the ''Vibrio cholerae'', binds to the enterocytes (intestinal cells) by the interaction between the subunit B and GM1 ganglioside[http://en.wikipedia.org/wiki/GM1] receptor on enterocytes, which then promotes the toxin endocytosis. Next, A1 turns to an active enzyme after separating with the A2 domain. After the A1 domain of subunit A of the toxin enters the cytosol, it activates adenylate cyclase to produce cAMP through G proteins, which triggers the activation of cystic fibrosis transmembrane conductance regulator (CFTR), leading to watery diarrhea: the efflux of water and ions from cells <ref>Jennifer McDowall, Cholera Toxin, EMBL-EMI, Interpro</ref>. | ||
[[Image:Picture1.png| | [[Image:Picture1.png|left|300px|thumb|Structure Notation of the RNA of CTX A, CLC RNA Workbench]] | ||
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== Evolution == | == Evolution == | ||
CTXφ Bacteriophage which is carried by ''Vibrio cholerae'' produces Cholera toxin. Cholera toxin is encoded by the ctxA and ctxB genes that are introduced into V. cholerae strains by horizontal gene transfer <ref>Davis B, Waldor M (2003). "Filamentous phages linked to virulence of Vibrio cholerae". Curr Opin Microbiol 6 (1): 35–42. doi:10.1016/S1369-5274(02)00005-X. PMID 12615217.</ref>. | CTXφ Bacteriophage which is carried by ''Vibrio cholerae'' produces Cholera toxin. Cholera toxin is encoded by the ctxA and ctxB genes that are introduced into V. cholerae strains by horizontal gene transfer <ref>Davis B, Waldor M (2003). "Filamentous phages linked to virulence of Vibrio cholerae". Curr Opin Microbiol 6 (1): 35–42. doi:10.1016/S1369-5274(02)00005-X. PMID 12615217.</ref>. | ||