Functional Research Of The Fatty Acid Binding Proteins In Haemaphysalis Flava

Fatty acid binding proteins（FABP）are small proteins that exist widely and play an important role in the transport and metabolism of Fatty acids in cells,and are essential to parasites that cannot synthesize most of their own lipids.The structure,function and mechanism of tick FABP are unknown,so the author conducted the following three studies:1.Primers were designed based on the transcript library of Haemaphysalis flava.The 5’and 3’ Contig879 sequences were amplified by RACE method to obtain the full length of the Hf FABP gene.The full length of Hf FABP gene was 1446 bp.The ORF was 399 bp in size and encoded 132 amino acids.RT-PCR showed that Hf FABP gene expression level was higher in adult tick stage,1/4 full blood state and ovarian organ.The expression level of Hf FABP increased gradually during egg hatching.2.HfFABP dsRNA was synthesized using the T7 RiboMAX^TM Express RNAi System and injected into the newly fully engorged female adult ticks through the spiracle.Compared with the control group,female ticks in the experimental group laid less eggs,decreased by about 62.25%,and had 30.96±6.25% egg deformity.The hatching rate of tick eggs in experimental group decreased significantly,and was only 40.27±6.15%.3.Fresh tick egg protein components were analyzed by LC/MS/MS method,and 112 and 113 high confidence proteins（peptides≥2）were identified respectively.Twenty of them were selected and the influence of interference was measured by PRM method.The results showed that,Neutrophil Elastase inhibitor,Aspartic Protease,heme-binding aspartic Proteinase,Midgut cysteine The abundance of Proteinase,Vitellogenin,Ferritin-2 and Heat shock protein 83 decreased significantly,suggesting that Hf FABP is involved in the synthesis or transport of inhibitors,proteases,Vg and other proteins.