Human Secreted Ly-6/uPAR Related Protein-1 (SLURP-1) Is a Selective Allosteric Antagonist of α7 Nicotinic Acetylcholine Receptor
Autor: | D.S. Kulbatskii, Alexey V. Feofanov, M. V. Astapova, Victor I. Tsetlin, Morten S. Thomsen, Dmitry A. Dolgikh, Denis S. Kudryavtsev, Ekaterina N. Lyukmanova, Jens D. Mikkelsen, M L Bychkov, Mikhail P. Kirpichnikov, Zakhar O. Shenkarev, Igor E. Kasheverov, Mikhail A. Shulepko |
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Jazyk: | angličtina |
Rok vydání: | 2016 |
Předmět: |
Keratinocytes
0301 basic medicine Nicotinic Acetylcholine Receptors alpha7 Nicotinic Acetylcholine Receptor Xenopus lcsh:Medicine Biochemistry Epithelium Animal Cells Muscarinic acetylcholine receptor M5 Muscarinic acetylcholine receptor Mecamylamine Medicine and Health Sciences Antigens Ly Receptor lcsh:Science Multidisciplinary Muscarinic acetylcholine receptor M3 Muscarinic acetylcholine receptor M2 Animal Models Recombinant Proteins Cell biology Nicotinic agonist Xenopus Oocytes Vertebrates Frogs Engineering and Technology Cellular Types Anatomy Protein Binding Research Article Signal Transduction medicine.drug Cell Binding Cell Physiology Transmembrane Receptors Biology Research and Analysis Methods Cell Line Amphibians 03 medical and health sciences Model Organisms Allosteric Regulation Affinity Purification medicine Humans Animals Acetylcholine receptor lcsh:R Organisms Biology and Life Sciences Proteins Epithelial Cells Cell Biology Urokinase-Type Plasminogen Activator Biological Tissue 030104 developmental biology Acetylcholine Receptors Signal Processing Muscarinic Acetylcholine Receptors lcsh:Q Purification Techniques |
Zdroj: | PLoS ONE, Vol 11, Iss 2, p e0149733 (2016) PLoS ONE |
ISSN: | 1932-6203 |
Popis: | SLURP-1 is a secreted toxin-like Ly-6/uPAR protein found in epithelium, sensory neurons and immune cells. Point mutations in the slurp-1 gene cause the autosomal inflammation skin disease Mal de Meleda. SLURP-1 is considered an autocrine/paracrine hormone that regulates growth and differentiation of keratinocytes and controls inflammation and malignant cell transformation. The majority of previous studies of SLURP-1 have been made using fusion constructs containing, in addition to the native protein, extra polypeptide sequences. Here we describe the activity and pharmacological profile of a recombinant analogue of human SLURP-1 (rSLURP-1) differing from the native protein only by one additional N-terminal Met residue. rSLURP-1 significantly inhibited proliferation (up to ~ 40%, EC50 ~ 4 nM) of human oral keratinocytes (Het-1A cells). Application of mecamylamine and atropine,--non-selective inhibitors of nicotinic acetylcholine receptors (nAChRs) and muscarinic acetylcholine receptors, respectively, and anti-α7-nAChRs antibodies revealed α7 type nAChRs as an rSLURP-1 target in keratinocytes. Using affinity purification from human cortical extracts, we confirmed that rSLURP-1 binds selectively to the α7-nAChRs. Exposure of Xenopus oocytes expressing α7-nAChRs to rSLURP-1 caused a significant non-competitive inhibition of the response to acetylcholine (up to ~ 70%, IC50 ~ 1 μM). It was shown that rSLURP-1 binds to α7-nAChRs overexpressed in GH4Cl cells, but does not compete with 125I-α-bungarotoxin for binding to the receptor. These findings imply an allosteric antagonist-like mode of SLURP-1 interaction with α7-nAChRs outside the classical ligand-binding site. Contrary to rSLURP-1, other inhibitors of α7-nAChRs (mecamylamine, α-bungarotoxin and Lynx1) did not suppress the proliferation of keratinocytes. Moreover, the co-application of α-bungarotoxin with rSLURP-1 did not influence antiproliferative activity of the latter. This supports the hypothesis that the antiproliferative activity of SLURP-1 is related to 'metabotropic' signaling pathway through α7-nAChR, that activates intracellular signaling cascades without opening the receptor channel. |
Databáze: | OpenAIRE |
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