MacMARCKS is not essential for phagocytosis in macrophages.
MacMARCKS (also known as myristoylated alanine-rich protein kinase C substrate (MARCKS)-related protein) is a member of the MARCKS family of protein kinase C substrates. MacMARCKS contains within it a basic effector domain that contains the serine residues that are phosphorylated by protein kinase C, as well as a calcium/calmodulin and actin-binding site. Two previous reports demonstrated that a macrophage cell line expressing a mutant form of MacMARCKS that lacks the effector domain is defective in phagocytosis and cell adhesion (Zhu, Z., Bao, Z., and Li, J. (1995) J. Biol. Chem. 270, 17652-17655; Li, J., Zhu, Z., and Bao, Z. (1996) J. Biol. Chem. 271, 12985-12990). We report here that macrophages from MacMARCKS null mice phagocytose and spread normally. Thus, although MacMARCKS is recruited to phagosomes, it is not absolutely required for phagocytosis.
Underhill
D M
DM
Department of Immunology, University of Washington, H-574 Health Sciences, Seattle, Washington 98195, USA.
Chen
J
J
Allen
L A
LA
Aderem
A
A
D000818:Animals; D002148:Calmodulin-Binding Proteins; D002460:Cell Line; D047908:Intracellular Signaling Peptides and Proteins; D008264:Macrophages / Q000276:immunology*; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D008840:Microfilament Proteins; D010587:Phagocytosis / Q000502:physiology*
D002148:Calmodulin-Binding Proteins; D047908:Intracellular Signaling Peptides and Proteins; C512945:Marcksl1 protein, mouse; D008565:Membrane Proteins; D008840:Microfilament Proteins