PACAP key interactions with PAC1, VPAC1, and VPAC2 identified by molecular dynamics simulations

The neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) belongs to the glucagon/secretin family. PACAP interacts with the pituitary adenylate cyclase-activating polypeptide receptor type 1 (PAC1) and vasoactive intestinal peptide receptors 1 and 2 (VPAC1 and VPAC2), exhibiting functions in the immune, endocrine, and nervous systems. This peptide is upregulated in numerous instances of brain injury, acting as a neuroprotective agent. It can also suppress HIV-1 and SARS-CoV-2 viral replication in vitro. This work aimed to identify, in each peptide-receptor system, the most relevant residues for complex stability and interaction energy communication via Molecular Dynamics (MD), Free Energy calculations, and Protein-energy networks, thus revealing in detail the underlying mechanisms of activation of these receptors. Hydrogen bond formation, interaction energies, and computational alanine scanning between PACAP and its receptors showed that His1, Asp3, Arg12, Arg14, and Lys15 are crucial to the peptide's stability. Furthermore, several PACAP interactions with structurally conserved positions deemed necessary in GPCR B1 activation, including Arg2.60, Lys2.67, and Glu7.42, were significant for the peptide's stability within the receptors. According to the protein-energy network, the connection between Asp3 of PACAP and the receptors' conserved Arg2.60 represents a critical energy communication hub in all complexes. Additionally, the ECDs of the receptors were also found to function as energy communication hubs for PACAP. Although the overall binding mode of PACAP in the three receptors was found to be highly conserved, Arg12 and Tyr13 of PACAP were more prominent in complex with PAC1, while Ser2 of PACAP was with VPAC2. The detailed analyses performed in this work pave the way for using PACAP and its receptors as therapeutic targets.Communicated by Ramaswamy H. Sarma.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:42

Enthalten in:

Journal of biomolecular structure & dynamics - 42(2024), 6 vom: 01. März, Seite 3128-3144

Sprache:

Englisch

Beteiligte Personen:

Meireles, Fernando Augusto T P [VerfasserIn]
Antunes, Deborah [VerfasserIn]
Temerozo, Jairo R [VerfasserIn]
Bou-Habib, Dumith Chequer [VerfasserIn]
Caffarena, Ernesto Raul [VerfasserIn]

Links:

Volltext

Themen:

Binding mode
Free energy calculations
Journal Article
Molecular dynamics simulations
PAC1
PACAP
Pituitary Adenylate Cyclase-Activating Polypeptide
Protein energy network
Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I
Receptors, Pituitary Hormone
VPAC1
VPAC2

Anmerkungen:

Date Completed 22.03.2024

Date Revised 22.03.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1080/07391102.2023.2213349

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM357188047