Exploiting functional domains of GRK2/3 to alter the competitive balance of pro- and anticontractile signaling in airway smooth muscle.
Publication/Presentation Date
2-1-2014
Abstract
To clarify the potential utility of targeting GRK2/3-mediated desensitization as a means of manipulating airway smooth muscle (ASM) contractile state, we assessed the specificity of GRK2/3 regulation of procontractile and relaxant G-protein-coupled receptors in ASM. Functional domains of GRK2/3 were stably expressed, or siRNA-mediated GRK2/3 knockdown was performed, in human ASM cultures, and agonist-induced signaling was assessed. Regulation of contraction of murine tracheal rings expressing GRK2 C terminus was also assessed. GRK2/3 knockdown or expression of the GRK2 C terminus caused a significant (∼ 30-90%) increase in maximal β-agonist and histamine [phosphoinositide (PI) hydrolysis] signaling, without affecting the calculated EC50. GRK2 C-terminal expression did not affect signaling by methacholine, thrombin, or LTD4. Expression of the GRK2 N terminus or kinase-dead holo-GRK2 diminished (∼ 30-70%) both PI hydrolysis and Ca(2+) mobilization by every Gq-coupled receptor examined. Under conditions of GRK2 C-terminal expression, β-agonist inhibition of methacholine-stimulated PI hydrolysis was greater. Finally, transgenic expression of the GRK2 C terminus in murine ASM enabled ∼ 30-50% greater β-agonist-mediated relaxation of methacholine-induced contraction. Collectively these data demonstrate the relative selectivity of GRKs for the β2AR in ASM and the ability to exploit GRK2/3 functional domains to render ASM hyporesponsive to contractile agents while increasing responsiveness to bronchodilating β-agonist.
Volume
28
Issue
2
First Page
956
Last Page
965
ISSN
1530-6860
Published In/Presented At
Deshpande, D. A., Yan, H., Kong, K. C., Tiegs, B. C., Morgan, S. J., Pera, T., Panettieri, R. A., Eckhart, A. D., & Penn, R. B. (2014). Exploiting functional domains of GRK2/3 to alter the competitive balance of pro- and anticontractile signaling in airway smooth muscle. FASEB journal : official publication of the Federation of American Societies for Experimental Biology, 28(2), 956–965. https://doi.org/10.1096/fj.13-240226
Disciplines
Business Administration, Management, and Operations | Health and Medical Administration | Management Sciences and Quantitative Methods
PubMedID
24132623
Department(s)
Administration and Leadership
Document Type
Article