title: Interaction of the brain-specific protein p42IP4/centaurin-alpha1 with the peptidase nardilysin is regulated by the cognate ligands of p42IP4, PtdIns(3,4,5)P3 and Ins(1,3,4,5)P4, with stereospecificity.
abstract: The brain-specific protein p42IP4, also called centaurin-alpha1, specifically binds phosphatidylinositol 3,4,5-trisphosphate [PtdIns(3,4,5)P3] and inositol 1,3,4,5-tetrakisphosphate [Ins(1,3,4,5)P4]. Here, we investigate the interaction of p42IP4/centaurin-alpha1 with nardilysin (NRDc), a member of the M16 family of zinc metalloendopeptidases. Members of this peptidase family exhibit enzymatic activity and also act as receptors for other proteins. We found that p42IP4/centaurin-alpha1 binds specifically to NRDc from rat brain. We further detected that centaurin-alpha2, a protein that is highly homologous to p42IP4/centaurin-alpha1 and expressed ubiquitously, also binds to NRDc. In vivo interaction was demonstrated by co-immunoprecipitation of p42IP4/centaurin-alpha1 with NRDc from rat brain. The acidic domain of NRDc (NRDc-AD), which does not participate in catalysis, is sufficient for the protein interaction with p42IP4. Interestingly, preincubation of p42IP4 with its cognate ligands D-Ins(1,3,4,5)P4 and the lipid diC8PtdIns(3,4,5)P3 negatively modulates the interaction between the two proteins. D-Ins(1,3,4,5)P4 and diC8PtdIns(3,4,5)P3 suppress the interaction with virtually identical concentration dependencies. This inhibition is highly ligand specific. The enantiomer L-Ins(1,3,4,5)P4 is not effective. Similarly, the phosphoinositides diC8PtdIns(3,4)P2, diC8PtdIns(3,5)P2 and diC8PtdIns(4,5)P2 all have no influence on the interaction. Further experiments revealed that endogenous p42IP4 from rat brain binds to glutathione-S-transferase (GST)-NRDc-AD. The proteins dissociate from each other when incubated with D-Ins(1,3,4,5)P4, but not with inositol 1,4,5-trisphosphate [Ins(1,4,5)P3]. In summary, we demonstrate that p42IP4 binds to NRDc via the NRDc-AD, and that this interaction is controlled by the cognate cellular ligands of p42IP4/centaurin-alpha1. Thus, specific ligands of p42IP4 can modulate the recruitment of proteins, which are docked to p42IP4, to specific cellular compartments.
authors.affiliation: Institut für Neurobiochemie, Medizinische Fakultät der Otto-von-Guericke-Universität Magdeburg, Magdeburg, Germany.
authors.forename: Rolf
authors.initials: R
authors.lastname: Stricker
authors.forename: K Martin
authors.initials: KM
authors.lastname: Chow
authors.forename: Daniela
authors.initials: D
authors.lastname: Walther
authors.forename: Theodor
authors.initials: T
authors.lastname: Hanck
authors.forename: Louis B
authors.initials: LB
authors.lastname: Hersh
authors.forename: Georg
authors.initials: G
authors.lastname: Reiser
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000737:chemistry / Q000378:metabolism* / Q000502:physiology*; D000818:Animals; D015153:Blotting, Western; D001923:Brain Chemistry / Q000502:physiology*; D004591:Electrophoresis, Polyacrylamide Gel; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D047468:Immunoprecipitation; D066298:In Vitro Techniques; D007295:Inositol Phosphates / Q000737:chemistry / Q000502:physiology*; D008024:Ligands; D008666:Metalloendopeptidases / Q000737:chemistry / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000378:metabolism* / Q000502:physiology*; D018129:Phosphatidylinositol Phosphates / Q000737:chemistry / Q000502:physiology*; D011485:Protein Binding; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000378:metabolism; D013237:Stereoisomerism
chemical_list: C100956:ADAP1 protein, human; D048868:Adaptor Proteins, Signal Transducing; D007295:Inositol Phosphates; D008024:Ligands; D009419:Nerve Tissue Proteins; D018129:Phosphatidylinositol Phosphates; D011993:Recombinant Fusion Proteins; C060974:phosphatidylinositol 3,4,5-triphosphate; C081655:inositol-1,3,4,5-tetrakisphosphate; D005982:Glutathione Transferase; D008666:Metalloendopeptidases; C087976:nardilysin