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bioRxiv · 10.1101/2024.02.23.581834

Is myeloid-derived growth factor a ligand of the sphingosine-1-phosphate receptor 2?

Zheng, Y.-S.·Liu, Y.-L.·Xu, Z.-G.·He, C.·Guo, Z.-Y.
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Abstract

Secretory myeloid-derived growth factor (MYDGF) exerts beneficial effects on organ repair, probably via a plasma membrane receptor; however, the identity of the expected receptor has remained elusive. In a recent study, MYDGF was reported as an agonist of the sphingosine-1-phosphate receptor 2 (S1PR2), an A-class G protein-coupled receptor that mediates the functions of the signaling lipid, sphingosine-1-phosphate (S1P). In the present study, we conducted living cell-based functional assays to test whether S1PR2 is a receptor for MYDGF. In the NanoLuc Binary Technology (NanoBiT)-based {beta}-arrestin recruitment assay and the cAMP-response element (CRE)-controlled NanoLuc reporter assay, S1P could efficiently activate human S1PR2 overexpressed in human embryonic kidney (HEK) 293T cells; however, recombinant human MYDGF, overexpressed either from Escherichia coli or HEK293 cells, had no detectable effect. Thus, the results demonstrated that human MYDGF is not a ligand of human S1PR2. Considering the high conservation of MYDGF and S1PR2 in evolution, MYDGF is also probably not a ligand of S1PR2 in other vertebrates.

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Zheng, Y.-S., Liu, Y.-L., Xu, Z.-G., He, C., Guo, Z.-Y.. 2024-02-24. Is myeloid-derived growth factor a ligand of the sphingosine-1-phosphate receptor 2?. https://doi.org/10.1101/2024.02.23.581834

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