Role for plastin in host defense distinguishes integrin signaling from cell adhesion and spreading.
Integrin ligation activates both cell adhesion and signal transduction, in part through reorganization of the actin cytoskeleton. Plastins (also known as fimbrins) are actin-crosslinking proteins of the cortical cytoskeleton present in all cells and conserved from yeast to mammals. Here we show that plastin-deficient polymorphonuclear neutrophils (PMN) are deficient in killing the bacterial pathogen Staphylococcus aureus in vivo and in vitro, despite normal phagocytosis. Like integrin beta2-deficient PMN, plastin-deficient PMN cannot generate an adhesion-dependent respiratory burst, because of markedly diminished integrin-dependent syk activation. Unlike beta2(-/-) PMN, plastin-deficient PMN adhere and spread normally. Deficiency of plastin thus separates the classical integrin receptor functions of adhesion and spreading from intracellular signal transduction.
Chen
Hua
H
Program in Microbial Pathogenesis and Host Defense and University of California, San Francisco, San Francisco, CA 94143, USA.
Mocsai
Attila
A
Zhang
Hong
H
Ding
Rong-Xian
RX
Morisaki
J Hiroshi
JH
White
Michael
M
Rothfork
Jacob M
JM
Heiser
Patrick
P
Colucci-Guyon
Emma
E
Lowell
Clifford A
CA
Gresham
Hattie D
HD
Allen
Paul M
PM
Brown
Eric J
EJ
D000818:Animals; D018821:CD18 Antigens / Q000502:physiology*; D002448:Cell Adhesion; D002465:Cell Movement; D004792:Enzyme Precursors / Q000502:physiology; D007113:Immunity, Innate; D047908:Intracellular Signaling Peptides and Proteins; D008562:Membrane Glycoproteins; D051379:Mice; D008810:Mice, Inbred C57BL; D008840:Microfilament Proteins; D009504:Neutrophils / Q000276:immunology* / Q000502:physiology; D010750:Phosphoproteins / Q000502:physiology*; D011505:Protein-Tyrosine Kinases / Q000502:physiology; D016897:Respiratory Burst; D015398:Signal Transduction / Q000502:physiology*; D013203:Staphylococcal Infections / Q000276:immunology; D000072377:Syk Kinase
D018821:CD18 Antigens; D004792:Enzyme Precursors; D047908:Intracellular Signaling Peptides and Proteins; D008562:Membrane Glycoproteins; D008840:Microfilament Proteins; D010750:Phosphoproteins; C026742:plastin; D011505:Protein-Tyrosine Kinases; D000072377:Syk Kinase; C000606897:Syk protein, mouse