Valosin-containing protein from the hard tick Haemaphysalis longicornis: effects of dsRNA-mediated HlVCP gene silencing.

We report the cloning and characterization of a cDNA encoding the valosin-containing protein (VCP) from the Haemaphysalis longicornis tick (HlVCP). The full-length HlVCP is 2782 bp and codes for 808 amino acids of a deduced protein with a predicted molecular mass of 89.9 kDa. The domain structure analysis revealed that the deduced protein has 2 Walker A domains, 2 Walker B domains, a Cdc48 domain, and a polyQ-binding domain. The mouse anti-HlVCP serum recognized a 97 kDa native protein in the salivary glands, midgut, and synganglion. RT-PCR analysis revealed that the native VCP was expressed throughout the developing stages and in tick organs. HlVCP silencing resulted in a decrease in tick body mass after blood feeding. This study not only contributes to a growing understanding of the ATPase gene family but also lays the groundwork for future studies on protein secretion and host-tick interaction. This study is the first report of the VCP gene from Chelicerata, which include spiders, scorpions, and ticks.