β2-adrenoceptor-induced modulation of transglutaminase 2 transamidase activity in cardiomyoblasts

Tools

Vyas, F.S., Nelson, C.P. ORCID: 0000-0003-1034-140X, Freeman, F. ORCID: 0000-0002-9816-266X, Boocock, D.J. ORCID: 0000-0002-7333-3549, Hargreaves, A.J. ORCID: 0000-0001-9754-5477 and Dickenson, J.M. ORCID: 0000-0002-9683-969X, 2017. β2-adrenoceptor-induced modulation of transglutaminase 2 transamidase activity in cardiomyoblasts. European Journal of Pharmacology. ISSN 0014-2999

Preview

Text
PubSub9005_Nelson.pdf - Post-print
Download (2MB) | Preview

Official URL: http://doi.org/10.1016/j.ejphar.2017.07.043

Abstract

Tissue transglutaminase 2 (TG2) is modulated by protein kinase A (PKA) mediated phosphorylation: however, the precise mechanism(s) of its modulation by G-protein coupled receptors coupled to PKA activation are not fully understood. In the current study we investigated the potential regulation of TG2 activity by the β2-adrenoceptor in rat H9c2 cardiomyoblasts. Transglutaminase transamidation activity was assessed using amine-incorporating and protein cross-linking assays. TG2 phosphorylation was determined via immunoprecipitation and Western blotting. The long acting β2-adrenoceptor agonist formoterol induced time- and concentration-dependent increases in TG2 transamidation. Increases in TG2 activity were reduced by the TG2 inhibitors Z-DON (Benzyloxycarbonyl-(6-Diazo-5-oxonorleucinyl)-L-valinyl-L-prolinyl-L-leucinmethylester) and R283 (1,3,dimethyl-2[2-oxo-propyl]thio)imidazole chloride). Responses to formoterol were blocked by pharmacological inhibition of PKA, extracellular signal-regulated kinase 1 and 2 (ERK1/2), or phosphatidylinositol 3-kinase (PI-3K) signalling. Furthermore, the removal of extracellular Ca2+ also attenuated formoterol-induced TG2 activation. Fluorescence microscopy demonstrated TG2-induced biotin-X-cadaverine incorporation into proteins. Formoterol increased the levels of TG2-associated phosphoserine and phosphothreonine, which were blocked by inhibition of PKA, ERK1/2 or PI-3K signalling. Subsequent proteomic analysis identified known (e.g. lactate dehydrogenase A chain) and novel (e.g. Protein S100-A6) protein substrates for TG2. Taken together, the data obtained suggest that β2-adrenoceptor-induced modulation of TG2 represents a novel paradigm in β2-adrenoceptor cell signalling, expanding the repertoire of cellular functions responsive to catecholamine stimulation.

Item Type:

Journal article

Publication Title:

European Journal of Pharmacology

Creators:

Vyas, F.S., Nelson, C.P., Freeman, F., Boocock, D.J., Hargreaves, A.J. and Dickenson, J.M.

Publisher:

Elsevier B.V.

Date:

25 July 2017

ISSN:

0014-2999