Rat p67 GBP Is Induced by Interferon-γ and Isoprenoid-Modified in Macrophages

• Published in: Biochemical and biophysical research communications 1996-07, Vol.224 (2), p.528-534
• Main Authors: Vestal, Deborah J., Buss, Janice E., Kelner, Gregory S., Maciejewski, Dominique, Asundi, Vinod K., Maki, Richard A.
• Format: Article
• Language: English
• Subjects: Animals; Animals, Newborn; Base Sequence; Bone Marrow Cells; Cells, Cultured; DNA Primers; GTP-Binding Proteins - biosynthesis; GTP-Binding Proteins - isolation & purification; Immunoblotting; Interferon-gamma - pharmacology; Lipopolysaccharides - pharmacology; Macrophages - drug effects; Macrophages - metabolism; Mevalonic Acid - metabolism; Microglia - drug effects; Microglia - metabolism; Molecular Sequence Data; Molecular Weight; Polymerase Chain Reaction; Protein Prenylation; Rats; Rats, Sprague-Dawley
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1006/bbrc.1996.1060

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-γ 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-γ 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-γ-activated macrophages and when the gene for p67 was transfected into COS cells. This is the first demonstration ofin vivoprenylation 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.