A Shared Genetic Mechanism for Melanotic Encapsulation of CM–Sephadex Beads and a Malaria Parasite,Plasmodium cynomolgiB, in the Mosquito,Anopheles gambiae

• Published in: Experimental parasitology Vol. 84; no. 3; pp. 380 - 386
• Main Authors: Gorman, M.J., Cornel, A.J., Collins, F.H., Paskewitz, S.M.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.12.1996
• Subjects: Anopheles gambiae; genetics; insect immunity; malaria; melanotic encapsulation; mosquito; Plasmodium cynomolgiB; refractoriness; Sephadex beads; Sephadex beads; melanotic encapsulation; genetics; Anopheles gambiae; refractoriness; Plasmodium cynomolgiB; malaria; insect immunity; mosquito
• ISSN: 0014-4894; 1090-2449
• DOI: 10.1006/expr.1996.0126

APlasmodium-refractory strain ofAnopheles gambiaethat melanizes ookinetes and intrathoracically inoculated CM–Sephadex beads was mated to aPlasmodium-susceptible strain that does not melanize the parasite or the beads. The F1progeny were then backcrossed to the susceptible strain. Backcross progeny were given a blood meal containing infectivePlasmodium cynomolgiB, and the parasites were allowed to develop for 6–7 days, at which time the infected mosquitoes were injected with CM–Sephadex beads. The next day the mosquitoes were dissected and the beads were scored for degree of melanization while the parasites were scored for degree of encapsulation. A Spearman rank order correlation test of the degree of correlation between the bead melanization phenotype and the parasite encapsulation phenotype gave a correlation coefficient of 0.74 (P< 0.01). This strong correlation between the two melanization responses suggests that the mechanisms for differential bead and parasite melanization of these two mosquito strains share at least one major gene.