Munc13 ‑4 mediates human neutrophil elastase‑induced airway mucin5AC hypersecretion by interacting with syntaxin2.

Munc13‑4 mediates human neutrophil elastase‑induced airway mucin5AC hypersecretion by interacting with syntaxin2.
Mol Med Rep. 2018 May 14;:
Authors: Xu R, Zhou J, Zhou XD, Li Q, Perelman JM, Kolosov VP
Abstract
The overexpression and hypersecretion of mucus is a hallmark of chronic pulmonary inflammatory disease. Mucin5AC (MUC5AC) is a major component of airway gel‑forming mucin. Members of the Unc13 (Munc13) protein family act as important activators of granule exocytosis from various types of mammalian cells. The present study aimed to determine the role of Munc13 family proteins in MUC5AC secretion via an in vitro study with BEAS‑2B and Calu‑3 cell lines. Reverse transcription‑quantitative polymerase chain reaction and western blotting indicated that stimulation of the cells with 100 nM human neutrophil elastase (hNE) for 1 h did not affect the expression of either unc13 homolog B (Munc13‑2) or unc13 homolog D (Munc13‑4), but immunofluorescence analysis demonstrated that hNE treatment was associated with the recruitment of Munc13‑4 to the plasma membrane. Co‑immunoprecipitation analysis indicated increased binding between Munc13‑4 and syntaxin2 followingh NE stimulation; however, Munc13‑2 formed a stable interaction with syntaxin2 with or without hNE stimulation. Subsequently, Munc13‑2 and Munc13‑4 expression levels were downregulated in BEAS‑2B and Calu‑3 cells using small interfering RNA (siRN...

Source: Molecular Medicine Reports - May 18, 2018 Category: Molecular Biology Tags: Mol Med Rep Source Type: research