Insights on the heparan sulphate-dependent externalisation of transglutaminase-2 (TG2) in glucose-stimulated proximal-like tubular epithelial cells

Furini, G ORCID: https://orcid.org/0000-0001-7206-7720, Burhan, I, Huang, L, Savoca, MP ORCID: https://orcid.org/0000-0002-6465-341X, Atobatele, A ORCID: https://orcid.org/0000-0002-9182-6742, Johnson, T and Verderio, E ORCID: https://orcid.org/0000-0001-9153-8997, 2020. Insights on the heparan sulphate-dependent externalisation of transglutaminase-2 (TG2) in glucose-stimulated proximal-like tubular epithelial cells. Analytical Biochemistry. ISSN 0003-2697

Preview

Text 1312273_Verderio.pdf - Post-print Download (1MB) | Preview

Abstract

The extracellular matrix crosslinking enzyme transglutaminase 2 (TG2) is highly implicated in tissue fibrosis that precedes end-stage kidney failure. TG2 is unconventionally secreted through extracellular vesicles in a way that depends on heparan sulphate (HS) proteoglycan syndecan-4 (Sdc4), the deletion of which reduces experimental kidney fibrosis as a result of lower extracellular TG2 in the tubule-interstitium. Here we establish a model of TG2 externalisation in NRK-52E tubular epithelial cells subjected to glucose stress. HS-binding TG2 mutants had reduced extracellular TG2 in transfected NRK-52E, suggesting that TG2-externalisation depends on an intact TG2 heparin binding site. Inhibition of N-ethylmaleimide sensitive factor (NSF) vesicle-fusing ATPase, which was identified in the recently elucidated TG2 kidney membrane-interactome, led to significantly lower TG2-externalisation, thus validating the involvement of membrane fusion in TG2 secretion. As cyclin-G-associated kinase (GAK) had emerged as a further TG2-partner in the fibrotic kidney, we investigated whether glucose-induced TG2-externalisation was accompanied by TG2 phosphorylation in consensus sequences of cyclin-dependent kinase (CDK). Glucose stress led to intense TG2 phosphorylation in serine/threonine CDK-target. TG2 phosphorylation by tyrosine kinases was also increased by glucose. Although the precise role of glucose-induced TG2 phosphorylation is unknown, these novel data suggest that phosphorylation may be involved in TG2 membrane-trafficking.

Item Type:	Journal article
Publication Title:	Analytical Biochemistry
Creators:	Furini, G., Burhan, I., Huang, L., Savoca, M.P., Atobatele, A., Johnson, T. and Verderio, E.
Publisher:	Elsevier
Date:	16 February 2020
ISSN:	0003-2697
Identifiers:	Number Type 10.1016/j.ab.2020.113628 DOI S000326971931187X Publisher Item Identifier 1312273 Other
Divisions:	Schools > School of Science and Technology
Record created by:	Linda Sullivan
Date Added:	30 Mar 2020 11:18
Last Modified:	31 May 2021 15:06
URI:	https://irep.ntu.ac.uk/id/eprint/39511

Actions (login required)

Edit View

Statistics

Views

Downloads