Myristoylated Alanine-Rich C-Kinase Substrate (MARCKS) Protein Regulation of Human Neutrophil Migration

Abstract

Neutrophil migration into infected tissues is essential for host defense, but products of activated neutrophils can be quite damaging to host cells. Neutrophil influx into the lung and airways and resultant inflammation characterizes diseases such as chronic obstructive pulmonary disease, bronchiectasis, and cystic fibrosis. To migrate, neutrophils must reorganize the actin cytoskeleton to establish a leading edge pseudopod and a trailing edge uropod. The actin-binding protein myristoylated alanine-rich C-kinase substrate (MARCKS) has been shown to bind and cross-link actin in a variety of cell types and to co-localize with F-actin in the leading edge lamellipodium of migrating fibroblasts. The hypothesis that MARCKS has a role in the regulation of neutrophil migration was tested using a cell-permeant peptide derived from the MARCKS myristoylated aminoterminus (MANS peptide). Treatment of isolated human neutrophils with MANS significantly inhibited both their migration and b2 integrin-dependent adhesion in response to N-formyl-methionyl-leucyl-phenylalanine (fMLF), IL-8, or leukotriene (LT)B 4 . The IC 50 for fMLF-induced migration and adhesion was 17.1 mM and 12.5 mM, respectively. MANS significantly reduced the F-actin content in neutrophils 30 seconds after fMLF stimulation, although the peptide did not alter the ability of cells to polarize or spread. MANS did not alter fMLF-induced increases in surface b2 integrin expression. These results suggest that MARCKS, via its myristoylated aminoterminus, is a key regulator of neutrophil migration and adhesion.

Mesenchymal Stem Cells Require MARCKS Protein for Directed Chemotaxis In Vitro

“…The synthetic MANS peptide used in these studies is identical to the myristoylated 24-amino acid domain on the N-terminus of MARCKS, and has been shown previously to attenuate degranulation in airway epithelium (30) and leukocytes (17) and also to inhibit migration of inflammatory cells in vitro (18).…”

“…Stimulation of other cell activities by RNS has been seen previously and could simply be a nonspecific response to a peptide. Nonetheless, RNS does serve as a useful negative control for MANS in a number of experimental settings (17,18,30). Since the function of the MARCKS amino terminus is thought to center on membrane binding, the inhibitory effects of MANS on MSC migration could be related to its interfering with MARCKS interaction with the cytoskeleton at the leading edge of the membrane in migrating cells.…”

“…MARCKS has previously been shown to bind F-actin filaments (13) and has been identified at the leading edge of polarized cells (12,14), and disruption of MARCKS can affect cell movement in vitro (15). In a number of in vivo and in vitro studies, a synthetic peptide identical to the Nterminus of MARCKS, named the MANS (myristoylated Nterminal sequence) peptide, has been shown to affect MARCKS function, resulting in disruption of MARCKS-dependent vesicular transport within cells as well as cell migration (16)(17)(18). Here, we sought to determine if MARCKS also is involved in directed chemotaxis of MSCs.…”

An Inhaled Inhibitor of Myristoylated Alanine-Rich C Kinase Substrate Reverses LPS-Induced Acute Lung Injury in Mice

“…BIO-11006 was synthesized by PolyPeptide (Torrence, CA). A concentration of 50 µM for N-terminal MARCKS inhibitors was shown to have optimal effects on attenuating neutrophil motility in vitro (4,5), and showed efficacy in preliminary in vivo studies in LPSinjured mice, so this concentration of BIO-11006 (equivalent to z0.75 mg/kg) was chosen for time-related studies detailed subsequently here.…”

Over-expression of phosphorylated MARCKS in the nicotine-derived nitrosamine ketone induced lung cancer mice

“…It was reported that the phosphorylation of MARCKS by protein kinase C results in the detachment of MARCKS from the membrane and suppress PIP2 by sequester manner (Gambhir et al, 2004;McLaughlin and Murray, 2005). At the same time it was also identified that in lungs, MARCKS especially phosphorylated MARCKS, plays a crucial role in controlling mucin secretion and inflammation (Eckert et al, 2010;Green et al, 2011;Li et al, 2001;Park et al, 2007;Singer et al, 2004). In addition, it was reported that phosphorylated MARCKS specifically regulate the cancer migration and metastasis (Chen et al, 2014;Chen and Rotenberg, 2010;Ghoul et al, 2006;Reddy et al, 2010;Techasen et al, 2010).…”