title: 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 beta2 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 microM and 12.5 microM, 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 beta2 integrin expression. These results suggest that MARCKS, via its myristoylated aminoterminus, is a key regulator of neutrophil migration and adhesion.
authors: Department of Clinical Sciences, College of Veterinary Medicine, North Caroline State University, Raleigh, North Carolina, USA.
authors: Rachael E
authors: RE
authors: Eckert
authors: Laura E
authors: LE
authors: Neuder
authors: Joungjoa
authors: J
authors: Park
authors: Kenneth B
authors: KB
authors: Adler
authors: Samuel L
authors: SL
authors: Jones
mesh_terms: D000199:Actins / Q000378:metabolism; D018821:CD18 Antigens / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D016764:Cell Polarity / Q000187:drug effects; D002630:Chemotactic Factors / Q000494:pharmacology; D002634:Chemotaxis, Leukocyte / Q000187:drug effects; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D000076250:Myristoylated Alanine-Rich C Kinase Substrate; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D010455:Peptides / Q000494:pharmacology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D000199:Actins; D018821:CD18 Antigens; D002630:Chemotactic Factors; D047908:Intracellular Signaling Peptides and Proteins; C000619710:MARCKS protein, human; D008565:Membrane Proteins; D010455:Peptides; D000076250:Myristoylated Alanine-Rich C Kinase Substrate; D009240:N-Formylmethionine Leucyl-Phenylalanine; D013755:Tetradecanoylphorbol Acetate