AmSNARES expression in Amblyomma maculatum feeding and pathogen transmission

Rickettsia parkeri, one of the causes of Spotted Fever Group Rickettsiosis, is carried by the Gulf Coast Tick (GCT), Amblyomma maculatum.  Pathogen transmission is thought to occur through a transcytotic mechanism in which the pathogen utilizes the protein machinery involved in vesicle docking. Tick salivary gland exocytosis processes appear to be essential to tick feeding success and may be important for pathogen trafficking. Our work to date has demonstrated the role of highly conserved vesicle and plasma membrane-bound protein receptors (SNAREs) in regulating protein secretions in tick salivary gland cells.  SNAP-25 participates in the assembly while NSF participates in the disassembly of the SNARE complex.  Gene expression of NSF  and SNAP -25 follows a cyclic regulation pattern with up and down regulation of the transcript during each of the three feeding phase. RNA interference demonstrates that NSF and SNAP-25 play an important role in prolonged tick feeding, since engorged tick weight was lower than control ticks.  In this study, we used next generation sequencing to investigate differential gene expression of AmSNAREs in A. maculatum infected with R. parkeri.