Molecular characterization of enolase fromHaemaphysalis longicornistick

Abstract

ABSTRACTEnolase is responsible for reversible conversion of D-2-phosphoglycerate and phosphoenolpyruvate in the glycolysis and gluconeogenesis important for cellular function. Here, we cloned a complete open reading frame (ORF) of enolase from theHaemaphysalis longicornistick and characterized its transcriptional and functional status. The ORF of enolase possesses 1,296 nucleotides encoding a mature protein of 432 amino acid residues. The molecular mass of enolase is 46,850.31 Da and the isoelectric point is 5.91. Enolase of the Jeju strainH. longicornishad the highest sequence similarity with the enolase ofH. flava(98%), followed byDermacentor silvarum(82%). We found motifs for enolase N-terminal, enolase C-terminal, magnesium binding site, and several phosphorylation sites such as casein kinase II phosphorylation, protein kinase C phosphorylation, and tyrosine kinase phosphorylation. RT-PCR showed enolase mRNA present in all developmental stages and most of the vital organelles ofH. longicornis. Notably, a higher transcript level was observed in synganglia compared with other areas based on real-time PCR, indicating that the role of enolase in the tick salivary gland is controlled by nerves arising in the synganglion. The functional status of enolase was characterized using RNA interference (RNAi) and caused significant (P < 0.05) reduction in feeding and reproduction as well as an abnormality in eggs and hatching. Taken together, these results indicate enolase as an important candidate for multiple vaccine antigens for controlling the tick population.Summary StatementWe identified enolase inHaemaphysalis longicornisticks in Jeju strain which has crucial role during blood engorgement, feeding duration, egg hatching, embryonic development physiological changes.