Inhibition of Calcium-Triggered Secretion by Hydrocarbon-Stapled Peptides

Authors

Ying Lai
Giorgio Fois
Jose R Flores
Michael J Tuvim
Qiangjun Zhou
Kailu Yang
Jeremy Leitz
John Peters
Yunxiang Zhang
Richard A Pfuetzner
Luis Esquivies
Philip Jones
Manfred Frick
Burton F Dickey
Axel T Brunger

Publication Date

3-1-2022

Journal

Nature

Abstract

Membrane fusion triggered by Ca2+ is orchestrated by a conserved set of proteins to mediate synaptic neurotransmitter release, mucin secretion and other regulated exocytic processes1-4. For neurotransmitter release, the Ca2+ sensitivity is introduced by interactions between the Ca2+ sensor synaptotagmin and the SNARE complex5, and sequence conservation and functional studies suggest that this mechanism is also conserved for mucin secretion6. Disruption of Ca2+-triggered membrane fusion by a pharmacological agent would have therapeutic value for mucus hypersecretion as it is the major cause of airway obstruction in the pathophysiology of respiratory viral infection, asthma, chronic obstructive pulmonary disease and cystic fibrosis7-11. Here we designed a hydrocarbon-stapled peptide that specifically disrupts Ca2+-triggered membrane fusion by interfering with the so-called primary interface between the neuronal SNARE complex and the Ca2+-binding C2B domain of synaptotagmin-1. In reconstituted systems with these neuronal synaptic proteins or with their airway homologues syntaxin-3, SNAP-23, VAMP8, synaptotagmin-2, along with Munc13-2 and Munc18-2, the stapled peptide strongly suppressed Ca2+-triggered fusion at physiological Ca2+ concentrations. Conjugation of cell-penetrating peptides to the stapled peptide resulted in efficient delivery into cultured human airway epithelial cells and mouse airway epithelium, where it markedly and specifically reduced stimulated mucin secretion in both systems, and substantially attenuated mucus occlusion of mouse airways. Taken together, peptides that disrupt Ca2+-triggered membrane fusion may enable the therapeutic modulation of mucin secretory pathways.

Keywords

Animals, Calcium, Hydrocarbons, Membrane Fusion, Mice, Mucins, Neurotransmitter Agents, Peptides, Respiratory Mucosa, SNARE Proteins

DOI

10.1038/s41586-022-04543-1

PMID

35322233

PMCID

PMC8967716

PubMedCentral® Posted Date

3-23-2022

PubMedCentral® Full Text Version

Post-print

Published Open-Access

yes