To investigate the role of PGRP-LD in parasites defense, we knocked down its expression in vivo via microinjection of gene-specific double stranded RNA and then analyzed the susceptibility of treated mosquitoes to infection with P. berghei. The level of pgrp-ld was reduced by approximately 67% 2-days post dsRNA treatment compared to dsGFP controls (Fig 1A), and we observed no significant cross reactivity with other long PGRPs, including PGRP-LA, -LB, -LC (Fig 1B). The gene discussed is PGLYRP1; the disease is infection.