title: Bombyx mori prothoracicostatic peptide receptor is allosterically activated via a Gα(i/o)-protein-biased signalling cascade by Drosophila sex peptide.
abstract: In insects, molting and metamorphosis are strictly regulated by ecdysteroids. Ecdysteroid synthesis is positively or negatively controlled by several neuropeptides. The prothoracicostatic peptide (PTSP) BmPTSP (Bombyx mori prothoracicostatic peptide), isolated from the larval brain of B. mori, has been demonstrated to inhibit ecdysteroid synthesis in the prothoracic glands (PGs) [Hua et al. (1999) J. Biol. Chem. 274, 31169-31173]. More recently, the newly recognized B. mori receptor for Drosophila melanogaster sex peptide (DmSP) has been identified as a receptor for BmPTSP. However, details on the signalling pathways and physiological functions of this receptor have remained elusive. In the present paper, we report the functional characterization of the BmPTSP receptor (BmPTSPR)/sex peptide (SP) receptor (SPR) using both mammalian and insect cells. Synthetic DmSP shows the potential to inhibit forskolin (FSK) or adipokinetic hormone (AKH)-induced cAMP-response element (CRE)-driven luciferase (Luc) activity in a manner comparable with synthetic BmPTSP1. However, DmSP displayed a much lower activity in triggering Ca²⁺ mobilization and internalization than did BmPTSP1. Additionally, 6-carboxy-fluorescein fluorophore (FAM)-labelled DmSP and BmPTSP3 were found to bind specifically to BmPTSPR/SPR. The binding of FAM-DmSP was displaced by unlabelled DmSP, but not by unlabelled BmPTSP1 and, vice versa, the binding of FAM-BmPTSP3 was blocked by unlabelled BmPTSP3, but not by unlabelled DmSP. Moreover, internalization assays demonstrated that BmPTSP1, but not DmSP, evoked recruitment of the Bombyx non-visual arrestin, Kurtz, to the activated BmPTSPR/SPR in the plasma membrane. This was followed by induction of internalization. This suggests that BmPTSP1 is probably an endogenous ligand specific for BmPTSPR/SPR. We therefore designate this receptor BmPTSPR. In contrast, DmSP is an allosteric agonist that is biased towards Gα(i/o)-dependent cAMP production and away from Ca²⁺ mobilization and arrestin recruitment.
authors.affiliation: *Institute of Biochemistry, College of Life Sciences, Zijingang Campus, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
authors.forename: Xiaobai
authors.initials: X
authors.lastname: He
authors.affiliation: *Institute of Biochemistry, College of Life Sciences, Zijingang Campus, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
authors.forename: Jiashu
authors.initials: J
authors.lastname: Zang
authors.affiliation: *Institute of Biochemistry, College of Life Sciences, Zijingang Campus, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
authors.forename: Huipeng
authors.initials: H
authors.lastname: Yang
authors.affiliation: †Zhejiang Provincial Key Laboratory of Medical Genetics, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China.
authors.forename: Haishan
authors.initials: H
authors.lastname: Huang
authors.affiliation: *Institute of Biochemistry, College of Life Sciences, Zijingang Campus, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Shi
authors.affiliation: *Institute of Biochemistry, College of Life Sciences, Zijingang Campus, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
authors.forename: Chenggang
authors.initials: C
authors.lastname: Zhu
authors.affiliation: *Institute of Biochemistry, College of Life Sciences, Zijingang Campus, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
authors.forename: Naiming
authors.initials: N
authors.lastname: Zhou
mesh_terms: D000494:Allosteric Regulation / Q000187:drug effects; D000818:Animals; D019390:Arrestins / Q000378:metabolism; D012831:Bombyx / Q000378:metabolism*; D020013:Calcium Signaling / Q000187:drug effects; D002462:Cell Membrane / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D019206:GTP-Binding Protein alpha Subunits, Gi-Go / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D007301:Insect Hormones / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D019476:Insect Proteins / Q000819:agonists* / Q000235:genetics / Q000378:metabolism; D036341:Intercellular Signaling Peptides and Proteins; D008024:Ligands; D009479:Neuropeptides / Q000819:agonists / Q000378:metabolism; D010455:Peptides / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D021381:Protein Transport / Q000187:drug effects; D018013:Receptors, Neuropeptide / Q000819:agonists* / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D061987:Sf9 Cells; D015398:Signal Transduction / Q000187:drug effects*; D009626:Terminology as Topic
chemical_list: D019390:Arrestins; D029721:Drosophila Proteins; D007301:Insect Hormones; D019476:Insect Proteins; D036341:Intercellular Signaling Peptides and Proteins; D008024:Ligands; C489175:Mst57Dc protein, Drosophila; D009479:Neuropeptides; D010455:Peptides; D018013:Receptors, Neuropeptide; D011994:Recombinant Proteins; C400522:alanyl-tryptophyl-glutaminyl-aspartyl-leucyl-asparagyl-seryl-alanyl-tryptophanamide; D019206:GTP-Binding Protein alpha Subunits, Gi-Go