Ticks are obligatory hematophagous ectoparasites, which can transmit various pathogens including bacteria, protozoa, and viruses via salivary secretion during feeding. Dopamine is known to be the most potent molecule for tick salivary secretion during blood feeding. Two dopamine receptors were recently characterized in tick salivary glands: dopamine receptor (D1) and invertebrate specific D1-like dopamine receptor (InvD1L). Dopamine’s action controlls the salivary glands by two distinct physiological actions: 1) inward fluid transport into the lumen of salivary glands acini via D1 receptor, 2) emptying lumen solute into salivary duct by pumping and gating via InvD1L. Between blood feeding, ticks can survive long period of time without blood feeding because of their highly developed osmoregulatory mechanisms. Off host ticks can maintain water balance by obtaining atmospheric water vapor via salivary glands. Understanding osmoregulation in ticks is crucial for the development of novel methods to prevent tick-borne disease transmission. S3-5

• Donghun Kim(Department of Applied Biology, Kyungpook National University)