Studies of the physiology and biochemistry and control of salivary secretion in feeding ixodid ticks will be continued. After reception of the primary stimulus (dopamine), the salivary glands utilize cyclic AMP (cAMP) and Ca2+ to help modulate cell activity during secretion. Little is known about how Ca2+ is mobilized during salivary gland function. Therefore, a role for the metabolism of plasma membrane phosphoinositides in signal transduction in the salivary glands will be studied. The question of whether enhanced hydrolysis of plasma membrane phosphatidylinositol 4,5-trisphosphate after agonist-receptor interaction mediates mobilization of intracellular Ca2+ will be explored. The physiological agonists of salivary gland phosphoinositide metabolism will be identified. The ability of these agonists to modulate salivary secretion with and without other known agonists of secretion i.e. dopamine and cAMP will be studied. The possible relationship between agonist-stimulated turnover of phosphoinositides and production and secretion of prostaglandins will be investigated. Possible protein kinase C activity in the salivary glands and its activation by another product of phosphoinositide metabolism, diacylglycerol and phorbol esters will be investigated. The """"""""second messenger"""""""" role for cAMP has been studied but little is known about functions of phosphoproteins. Therefore, the phosphoprotein phosphorylated by cAMP-dependent protein kinase to modulate protein phosphatase activity and its relationship to inhibition of protein phosphatase by Ca2+ will be investigated. Information about how metabolic pathways regulate secretion, either directly or indirectly, should shed light on synthesis and secretion of substances that contribute to a tick's successful feeding and their ability to vector pathogens. Ultimately the results may be useful for applied biology. Interference with an essential point in a metabolic pathway controlling salivary secretion could provide a new approach to tick control or the pathogens they vector.

National Institute of Health (NIH)
National Institute of Allergy and Infectious Diseases (NIAID)
Research Project (R01)
Project #
Application #
Study Section
Tropical Medicine and Parasitology Study Section (TMP)
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Oklahoma State University Stillwater
Earth Sciences/Resources
United States
Zip Code
Qian, Y; Yuan, J; Essenberg, R C et al. (1998) Prostaglandin E2 in the salivary glands of the female tick, Amblyomma americanum (L.): calcium mobilization and exocytosis. Insect Biochem Mol Biol 28:221-8
McSwain, J L; Luo, C; deSilva, G A et al. (1997) Cloning and sequence of a gene for a homologue of the C subunit of the V-ATPase from the salivary gland of the tick Amblyomma americanum (L). Insect Mol Biol 6:67-76
Qian, Y; Essenberg, R C; Dillwith, J W et al. (1997) A specific prostaglandin E2 receptor and its role in modulating salivary secretion in the female tick, Amblyomma americanum (L.). Insect Biochem Mol Biol 27:387-95
Luo, C; McSwain, J L; Tucker, J S et al. (1997) Cloning and sequence of a gene for the homologue of the stearoyl CoA desaturase from salivary glands of the tick Amblyomma americanum. Insect Mol Biol 6:267-71
Sauer, J R; McSwain, J L; Bowman, A S et al. (1995) Tick salivary gland physiology. Annu Rev Entomol 40:245-67
Sauer, J R; McSwain, J L; Essenberg, R C (1994) Cell membrane receptors and regulation of cell function in ticks and blood-sucking insects. Int J Parasitol 24:33-52
Qureshi, A E; Essenberg, R C; Sauer, J R (1994) Protein phosphatase 1 and 2A in tick salivary glands as assessed by responses to okadaic acid. Insect Biochem Mol Biol 24:309-17
Shipley, M M; Dillwith, J W; Essenberg, R C et al. (1993) Analysis of lipids in the salivary glands of Amblyomma americanum (L.): detection of a high level of arachidonic acid. Arch Insect Biochem Physiol 23:37-52
Shipley, M M; Dillwith, J W; Bowman, A S et al. (1993) Changes in lipids of the salivary glands of the lone star tick, Amblyomma americanum, during feeding. J Parasitol 79:834-42
McSwain, J L; Essenberg, R C; Sauer, J R (1992) Oral secretion elicited by effectors of signal transduction pathways in the salivary glands of Amblyomma americanum (Acari: Ixodidae). J Med Entomol 29:41-8

Showing the most recent 10 out of 14 publications