Soluble N-Ethylmaleimide-Sensitive Factor Attachment Protein Receptor-Derived Peptides for Regulation of Mast Cell Degranulation.

Yoosoo Yang,Jae Youl Cho,Jung-Mi Oh,Byoungjae Kong,Jaesung Hwang,Younghoon Jung,Joon-Bum Park,Dae-Hyuk Kweon

doi:10.3389/fimmu.2018.00725

Abstract

Vesicle-associated V-soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins and target membrane-associated T-SNAREs (syntaxin 4 and SNAP-23) assemble into a core trans-SNARE complex that mediates membrane fusion during mast cell degranulation. This complex plays pivotal roles at various stages of exocytosis from the initial priming step to fusion pore opening and expansion, finally resulting in the release of the vesicle contents. In this study, peptides with the sequences of various SNARE motifs were investigated for their potential inhibitory effects against SNARE complex formation and mast cell degranulation. The peptides with the sequences of the N-terminal regions of vesicle-associated membrane protein 2 (VAMP2) and VAMP8 were found to reduce mast cell degranulation by inhibiting SNARE complex formation. The fusion of protein transduction domains to the N-terminal of each peptide enabled the internalization of the fusion peptides into the cells equally as efficiently as cell permeabilization by streptolysin-O without any loss of their inhibitory activities. Distinct subsets of mast cell granules could be selectively regulated by the N-terminal-mimicking peptides derived from VAMP2 and VAMP8, and they effectively decreased the symptoms of atopic dermatitis in mouse models. These results suggest that the cell membrane fusion machinery may represent a therapeutic target for atopic dermatitis.

Highlights

Atopic dermatitis is a type of chronic skin disease that is associated with allergic inflammation
To search for potent peptide inhibitors that can interfere with sensitive factor attachment protein receptor (SNARE) complex formation and thereby reduce mast cell degranulation, seventeen 17-mer peptides were synthesized of which sequences were patterned after the N-terminal (N), middle (M), and C-terminal (C) regions of the SNARE motifs of SNAP-23 (SN23 and SC23), syntaxin 4 (Syn4), and VAMPs (Vp2, 4, 7, and 8) (Table 1; Figure 1)
The full-length soluble SNARE motifs of vesicle-associated membrane protein 2 (VAMP2), VAMP4, VAMP7, and VAMP8, which are known to be present in mast cell granules, were expressed and purified from E. coli

Summary

Introduction

Atopic dermatitis is a type of chronic skin disease that is associated with allergic inflammation. Upon the stimulation of the surface receptor FcεRI with crosslinked preformed IgE [2], the degranulation of mast cells is activated, and subsequently, their content of proinflammatory mediators is released via membrane fusion between preformed granules/vesicles and the outer cell membrane [3, 4]. The processes of vesicular transport, fusion, and the release of vesicle contents, including those occurring during mast cell degranulation, are mediated by the fusion machinery proteins known as the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins in all eukaryotic cells [3]. SNARE proteins are classified as vesicle-localized (V)-SNAREs and target-localized (T)-SNAREs depending on their cellular localization Both types of SNAREs mediate membrane fusion by forming a highly stable SNARE complex comprising four conserved SNARE motifs [5]

Methods

Results

Conclusion