Blood meal digestion in Ae. aegpti mosquitoes requires the synthesis and secretion of numerous proteases, the best characterized of which are serine proteases. The early trypsin protease (AeET) is synthesized from pre-existing mRNA and secreted into the lumen within the first 6 hr PBM, whereas the late phase serine proteases AaSPVI, AaSPVII, and AaLT, are transcribed, translated, and secreted between 18-30 hr PBM [31] . To determine if alpha-COPI functions are required for the synthesis and secretion of early and late phase serine proteases, we injected mosquitoes with Fluc and alpha-COPI dsRNA 3 days prior to blood feeding and used Western blotting to detect protease protein expression at 3 hr PBM (AeET) and 24 hr PBM (AaSPVI, AaSPVII, AaLT). As shown in Figure 9A , the pattern of AeET protein expression is similar in Fluc and alpha-COPI dsRNA injected mosquitoes, suggesting that alpha-COPI functions are not required for early phase blood meal digestion. However, as shown in Figure 9B , 100-400 ng of alpha-COPI dsRNA blocks expression of all three abundant late phase proteases at 24 hr PBM in a dose-dependent manner. Lack of late phase serine protease expression in alpha-COPI deficient mosquitoes was associated with ejection of the undigested blood meal between 12-30 hr PBM (data not shown).