title: Expression profile of prophenoloxidase-encoding (acppo6) gene of Plasmodium vivax-refractory strain of Anopheles culicifacies.
abstract: Anopheles culicifacies is the main vector for transmission of Plasmodium vivax malaria in the Indian subcontinent. A strain of An. culicifacies isolated from its natural niche displayed complete refractoriness to P. vivax by melanotic encapsulation of ookinetes. Prophenoloxidases are key components of the phenoloxidase cascade that leads to recognition and melanization of invading organisms. We isolated and cloned prophenoloxidase-encoding acppo6 gene of An. culicifacies and analyzed its expression profile under various regimens of immune challenge. The acppo6 was differentially expressed during various stages of larval development. The acppo6 transcription was also up-regulated in response to bacteria and Plasmodium vinckei petteri challenge. The transcript levels of the acppo6 gene were higher in naive adult refractory female mosquitoes as compared with female susceptible mosquitoes. Furthermore, the induction of acppo6 in the susceptible strain upon Plasmodium infection was negligible as compared with that of the refractory strain. The observation is suggestive of the role of acppo6 in effectuating a melanotic response in Plasmodium-incompetent naturally occurring refractory An. culicifacies strain.
authors.affiliation: Insect Resistance Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India.
authors.forename: Anil
authors.initials: A
authors.lastname: Sharma
authors.forename: Janneth
authors.initials: J
authors.lastname: Rodrigues
authors.forename: Mayur K
authors.initials: MK
authors.lastname: Kajla
authors.forename: Neema
authors.initials: N
authors.lastname: Agrawal
authors.forename: T
authors.initials: T
authors.lastname: Adak
authors.forename: Raj K
authors.initials: RK
authors.lastname: Bhatnagar
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000852:Anopheles / Q000201:enzymology* / Q000235:genetics* / Q000469:parasitology; D004156:Catechol Oxidase / Q000235:genetics* / Q000378:metabolism*; D004792:Enzyme Precursors / Q000235:genetics* / Q000378:metabolism*; D005260:Female; D020869:Gene Expression Profiling; D015971:Gene Expression Regulation, Enzymologic; D006790:Host-Parasite Interactions / Q000235:genetics; D008969:Molecular Sequence Data; D010966:Plasmodium vivax / Q000502:physiology*
chemical_list: D004792:Enzyme Precursors; C038451:pro-phenoloxidase; D004156:Catechol Oxidase