Cargando…

MMP activation–associated aminopeptidase N reveals a bivalent 14-3-3 binding motif

Aminopeptidase N (APN, CD13) is a transmembrane ectopeptidase involved in many crucial cellular functions. Besides its role as a peptidase, APN also mediates signal transduction and is involved in the activation of matrix metalloproteinases (MMPs). MMPs function in tissue remodeling within the extra...

Descripción completa

Detalles Bibliográficos
Autores principales: Kiehstaller, Sebastian, Ottmann, Christian, Hennig, Sven
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Society for Biochemistry and Molecular Biology 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7939381/
https://www.ncbi.nlm.nih.gov/pubmed/33109610
http://dx.doi.org/10.1074/jbc.RA120.014708
_version_ 1783661741450723328
author Kiehstaller, Sebastian
Ottmann, Christian
Hennig, Sven
author_facet Kiehstaller, Sebastian
Ottmann, Christian
Hennig, Sven
author_sort Kiehstaller, Sebastian
collection PubMed
description Aminopeptidase N (APN, CD13) is a transmembrane ectopeptidase involved in many crucial cellular functions. Besides its role as a peptidase, APN also mediates signal transduction and is involved in the activation of matrix metalloproteinases (MMPs). MMPs function in tissue remodeling within the extracellular space and are therefore involved in many human diseases, such as fibrosis, rheumatoid arthritis, tumor angiogenesis, and metastasis, as well as viral infections. However, the exact mechanism that leads to APN-driven MMP activation is unclear. It was previously shown that extracellular 14-3-3 adapter proteins bind to APN and thereby induce the transcription of MMPs. As a first step, we sought to identify potential 14-3-3–binding sites in the APN sequence. We constructed a set of phosphorylated peptides derived from APN to probe for interactions. We identified and characterized a canonical 14-3-3–binding site (site 1) within the flexible, structurally unresolved N-terminal APN region using direct binding fluorescence polarization assays and thermodynamic analysis. In addition, we identified a secondary, noncanonical binding site (site 2), which enhances the binding affinity in combination with site 1 by many orders of magnitude. Finally, we solved crystal structures of 14-3-3σ bound to mono- and bis-phosphorylated APN-derived peptides, which revealed atomic details of the binding mode of mono- and bivalent 14-3-3 interactions. Therefore, our findings shed some light on the first steps of APN-mediated MMP activation and open the field for further investigation of this important signaling pathway.
format Online
Article
Text
id pubmed-7939381
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher American Society for Biochemistry and Molecular Biology
record_format MEDLINE/PubMed
spelling pubmed-79393812021-06-08 MMP activation–associated aminopeptidase N reveals a bivalent 14-3-3 binding motif Kiehstaller, Sebastian Ottmann, Christian Hennig, Sven J Biol Chem Signal Transduction Aminopeptidase N (APN, CD13) is a transmembrane ectopeptidase involved in many crucial cellular functions. Besides its role as a peptidase, APN also mediates signal transduction and is involved in the activation of matrix metalloproteinases (MMPs). MMPs function in tissue remodeling within the extracellular space and are therefore involved in many human diseases, such as fibrosis, rheumatoid arthritis, tumor angiogenesis, and metastasis, as well as viral infections. However, the exact mechanism that leads to APN-driven MMP activation is unclear. It was previously shown that extracellular 14-3-3 adapter proteins bind to APN and thereby induce the transcription of MMPs. As a first step, we sought to identify potential 14-3-3–binding sites in the APN sequence. We constructed a set of phosphorylated peptides derived from APN to probe for interactions. We identified and characterized a canonical 14-3-3–binding site (site 1) within the flexible, structurally unresolved N-terminal APN region using direct binding fluorescence polarization assays and thermodynamic analysis. In addition, we identified a secondary, noncanonical binding site (site 2), which enhances the binding affinity in combination with site 1 by many orders of magnitude. Finally, we solved crystal structures of 14-3-3σ bound to mono- and bis-phosphorylated APN-derived peptides, which revealed atomic details of the binding mode of mono- and bivalent 14-3-3 interactions. Therefore, our findings shed some light on the first steps of APN-mediated MMP activation and open the field for further investigation of this important signaling pathway. American Society for Biochemistry and Molecular Biology 2021-01-13 /pmc/articles/PMC7939381/ /pubmed/33109610 http://dx.doi.org/10.1074/jbc.RA120.014708 Text en © 2020 © 2020 Kiehstaller et al. https://creativecommons.org/licenses/by/4.0/This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Signal Transduction
Kiehstaller, Sebastian
Ottmann, Christian
Hennig, Sven
MMP activation–associated aminopeptidase N reveals a bivalent 14-3-3 binding motif
title MMP activation–associated aminopeptidase N reveals a bivalent 14-3-3 binding motif
title_full MMP activation–associated aminopeptidase N reveals a bivalent 14-3-3 binding motif
title_fullStr MMP activation–associated aminopeptidase N reveals a bivalent 14-3-3 binding motif
title_full_unstemmed MMP activation–associated aminopeptidase N reveals a bivalent 14-3-3 binding motif
title_short MMP activation–associated aminopeptidase N reveals a bivalent 14-3-3 binding motif
title_sort mmp activation–associated aminopeptidase n reveals a bivalent 14-3-3 binding motif
topic Signal Transduction
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7939381/
https://www.ncbi.nlm.nih.gov/pubmed/33109610
http://dx.doi.org/10.1074/jbc.RA120.014708
work_keys_str_mv AT kiehstallersebastian mmpactivationassociatedaminopeptidasenrevealsabivalent1433bindingmotif
AT ottmannchristian mmpactivationassociatedaminopeptidasenrevealsabivalent1433bindingmotif
AT hennigsven mmpactivationassociatedaminopeptidasenrevealsabivalent1433bindingmotif