Structure-activity studies on neuropeptide S: identification of the amino acid residues crucial for receptor activation.
Neuropeptide S (NPS) has been recently recognized as the endogenous ligand for the previous orphan G-protein-coupled receptor GPR154, now referred to as the NPS receptor (NPSR). The NPS-NPSR receptor system regulates important biological functions such as sleeping/wakening, locomotion, anxiety, and food intake. To collect information on the mechanisms of interaction between NPS and its receptor, a classical structure-activity relationship study was performed. Human (h) NPS derivatives obtained by Ala and d-scan and N- and C-terminal truncation were assessed for their ability to stimulate calcium release in HEK293 cells expressing the human recombinant NPSR. The results of this study indicate that (i) the effect of hNPS is mimicked by the fragment hNPS-(1-10); (ii) Phe(2), Arg(3), and Asn(4) are crucial for biological activity; (iii) the sequence Thr(8)-Gly(9)-Met(10) is important for receptor activation, although with non-stringent chemical requirements; and (iv) the sequence Val(6)-Gly(7) acts as a hinge region between the two above-mentioned domains. However, the stimulatory effect of hNPS given intracerebroventricularly on mouse locomotor activity was not fully mimicked by hNPS-(1-10), suggesting that the C-terminal region of the peptide maintains importance for in vivo activity. In conclusion, this study identified the amino acid residues of this peptide most important for receptor activation.
Roth
Adelheid L
AL
Department of Biology, Psychiatry Center of Excellence for Drug Discovery, GlaxoSmithKline Pharmaceuticals, Via Alessandro Fleming 2, 37135 Verona, Italy.
Marzola
Erika
E
Department of Pharmaceutical Science and Biotechnology Center, University of Ferrara, Via Fossato di Mortara 19, 44100 Ferrara, Italy.
Rizzi
Anna
A
Department of Experimental and Clinical Medicine, Section of Pharmacology and Neuroscience Center, University of Ferrara, Via Fossato di Mortara 19, 44100 Ferrara, Italy.
Arduin
Marika
M
Department of Pharmaceutical Science and Biotechnology Center, University of Ferrara, Via Fossato di Mortara 19, 44100 Ferrara, Italy.
Trapella
Claudio
C
Department of Pharmaceutical Science and Biotechnology Center, University of Ferrara, Via Fossato di Mortara 19, 44100 Ferrara, Italy.
Corti
Corrado
C
Department of Biology, Psychiatry Center of Excellence for Drug Discovery, GlaxoSmithKline Pharmaceuticals, Via Alessandro Fleming 2, 37135 Verona, Italy.
Vergura
Raffaella
R
Department of Experimental and Clinical Medicine, Section of Pharmacology and Neuroscience Center, University of Ferrara, Via Fossato di Mortara 19, 44100 Ferrara, Italy.
Martinelli
Prisca
P
Department of Biology, Psychiatry Center of Excellence for Drug Discovery, GlaxoSmithKline Pharmaceuticals, Via Alessandro Fleming 2, 37135 Verona, Italy.
Salvadori
Severo
S
Department of Pharmaceutical Science and Biotechnology Center, University of Ferrara, Via Fossato di Mortara 19, 44100 Ferrara, Italy.
Regoli
Domenico
D
Department of Experimental and Clinical Medicine, Section of Pharmacology and Neuroscience Center, University of Ferrara, Via Fossato di Mortara 19, 44100 Ferrara, Italy.
Corsi
Mauro
M
Department of Biology, Psychiatry Center of Excellence for Drug Discovery, GlaxoSmithKline Pharmaceuticals, Via Alessandro Fleming 2, 37135 Verona, Italy.
Cavanni
Paolo
P
Department of Biology, Psychiatry Center of Excellence for Drug Discovery, GlaxoSmithKline Pharmaceuticals, Via Alessandro Fleming 2, 37135 Verona, Italy.
Caló
Girolamo
G
Department of Experimental and Clinical Medicine, Section of Pharmacology and Neuroscience Center, University of Ferrara, Via Fossato di Mortara 19, 44100 Ferrara, Italy. Electronic address: g.calo@unife.it.
Guerrini
Remo
R
Department of Pharmaceutical Science and Biotechnology Center, University of Ferrara, Via Fossato di Mortara 19, 44100 Ferrara, Italy.
D000595:Amino Acid Sequence; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000737:chemistry*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D051381:Rats; D043562:Receptors, G-Protein-Coupled / Q000737:chemistry; D011994:Recombinant Proteins / Q000737:chemistry; D013329:Structure-Activity Relationship
C484532:NPSR1 protein, human; D009479:Neuropeptides; D043562:Receptors, G-Protein-Coupled; D011994:Recombinant Proteins; C506531:neuropeptide S, human; D002118:Calcium