Genome sequence of Anopheles sinensis provides insight into genetics basis of mosquito competence for malaria parasites

Abstract

Background: Anopheles sinensis is an important mosquito vector of Plasmodium vivax, which is the most frequent and widely distributed cause of recurring malaria throughout Asia, and particularly in China, Korea, and Japan.

Results: We performed 454 next-generation sequencing and obtained a draft sequence of A. sinensis assembled into scaffolds spanning 220.8 million base pairs. Analysis of this genome sequence, we observed expansion and contraction of several immune-related gene families in anopheline relative to culicine mosquito species. These differences suggest that species-specific immune responses to Plasmodium invasion underpin the biological differences in susceptibility to Plasmodium infection that characterize these two mosquito subfamilies.

Conclusions: The A. sinensis genome produced in this study, provides an important resource for analyzing the genetic basis of susceptibility and resistance of mosquitoes to Plasmodium parasites research which will ultimately facilitate the design of urgently needed interventions against this debilitating mosquito-borne disease.

Figure 1

Repetitive elements in A. sinensis .

Figure 2

D. melanogaster protein length plotted against the orthologous protein length for A. sinensis. The red dashed line shows the results of a linear regression. The concordance of the two variables is presented with 95% confidence intervals. Perfect concordance (1.0) would indicate that all points fall on the line where x = y, depicted by the edge of the grey shading.

Figure 3

Gene ontology classifications for A. sinensis at level two. Gene ontology classifications included three components: biological processes, cellular components and molecular functions.

Figure 4

Ortholog delineation among the protein-coding gene repertoires of the four mosquito species and D. melanogaster. Membership of the categories of orthologous groups are depicted as follows: (i) 1:1:1:1:1 indicates single-copy orthologs in all species; (ii) N:N:N:N:N indicates multi-copy orthologs in all species; (iii) N in 1, N in 2, etc. indicates multi-copy orthologs in one or two species, etc; (iv) x:x:x:x:0, x:0:x:x:x, x:x:0:x:0 etc. indicates (by a 0) which of the five species, in the order listed above, did not contain single-copy or multi-copy orthologs. The remaining proportion of the sequence for each species exhibited no orthologs with genes in the other species (depicted as specific-specific in the figure).

Figure 5

The coverage of the microsynteny block of A. sinensis on the chromosome of A. gambiae .

Figure 6

The inferred supertree for four mosquito species and D. melanogaster. The topology of the supertree was evaluated by bootstrap percentages. Distances are in millions of years.