Variation and Difference Analysis on Content and Composition of Proteins in Haemolymph of the Fifth Instar Antheraea pernyi Larvae Infected by Nosema pernyi

In order to provide evidence for probing into immune response of Antheraea pernyi to Nosema pernyi(Np) infection,changes of the content and composition of haemolymph proteins in the 5th instar female and male Antheraea pernyi larvae that were administrated with Np spores were measured and analyzed.The results showed that contents of hemolymph proteins in the 5th instar female and male Antheraea pernyi larvae infected with Np spores varied differently with larval development.The hemolymph protein contents in female and male larvae increased extremely significantly(P0.01) at 24 h and 48 h after Np administration respectively,and lasted till 96 h.What's more,the content of haemolymph proteins in female larvae was extremely significantly higher than that of the male(P0.01).At 120 h after infection,the haemolymph protein contents in both female and male larvae had no significant difference with the control group(P0.05).SDS-PAGE analysis revealed that the composition of haemolymph proteins in the 5th instar larvae infected by Np spores was similar to that of the control group,both showing 20 protein bands with molecular weights ranging from 20.1 to 97.2 kD.The protein bands of about 44 kD in haemolymph of the female and male larvae were obviously thicker at 96 h after Np infection.The protein band of about 28 kD was obviously thicker at 144 h in female larvae and at 120 h in male larvae after Np infection.Moreover,the protein band of about 42 kD in male larvae was obviously thicker at 120~168 h after Np infection,but showed no obvious difference with the control group at 192 h.These experimental results suggest that there are certain changes in contents and compositions of haemolymph proteins in the 5th instar Antheraea pernyi larvae,and the changes in female larvae are different with those in male ones.