Influence of blood feeding and L. infantum infection on the dynamics of P. perniciosus trypsins expression. (A) The graph shows PperTryp1, PperTryp2 and PperTryp3 expression as fold over the reference housekeeping gene (PpPerS7 ribosomal protein) before and after the blood feeding (6 hours, 24 hours, 72 hours and 10 days). Each column represents the mean of ten females. S, sugar fed sand flies; B, blood fed sand flies; I, blood fed and L. infantum infected sand flies. The statistically significant difference between the infected and uninfected sand flies is indicated by (*). (B) The graph shows significant difference of PperTryp3 expression in uninfected (B_24) and infected (I_24) sand flies 24 hours after blood feeding; Mann-Whitney U Test (U = 20; Z = 2.268), p = 0.023.