Rat p67 GBP is induced by interferon-gamma and isoprenoid-modified in macrophages.
The guanylate binding proteins, GBPs, are a family of interferon-induced GTP-binding proteins that include the rat p67. We report here that rat p67, for which interferon regulation had not previously been demonstrated, is induced by IFN-gamma and also by LPS in both cultured bone marrow-derived macrophages and microglia. The basal level of rat p67 in macrophages is low but increases dramatically between 2 and 4 hours after treating cells with either IFN-gamma or LPS. It then remains elevated over the next 24 hours. Rat p67 is isoprenoid modified. The isoprenoid modification was detected in p67 isolated both from primary IFN-gamma-activated macrophages and when the gene for p67 was transfected into COS cells. This is the first demonstration of in vivo prenylation of a GBP. The interferon regulation and prenylation of rat p67 point toward this protein being significant in the functions of both activated macrophages and microglia.
Vestal
D J
DJ
Burnham Institute, La Jolla, California 92037, USA. djvestal@ljcrf.edu
Buss
J E
JE
Kelner
G S
GS
Maciejewski
D
D
Asundi
V K
VK
Maki
R A
RA
D000818:Animals; D000831:Animals, Newborn; D001483:Base Sequence; D001854:Bone Marrow Cells; D002478:Cells, Cultured; D017931:DNA Primers; D019204:GTP-Binding Proteins / Q000096:biosynthesis* / Q000302:isolation & purification; D015151:Immunoblotting; D007371:Interferon-gamma / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism*; D008798:Mevalonic Acid / Q000378:metabolism*; D017628:Microglia / Q000187:drug effects / Q000378:metabolism; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016133:Polymerase Chain Reaction; D017368:Protein Prenylation; D051381:Rats; D017207:Rats, Sprague-Dawley
D017931:DNA Primers; D008070:Lipopolysaccharides; D007371:Interferon-gamma; D019204:GTP-Binding Proteins; D008798:Mevalonic Acid