Guanylate Binding Protein 6 (GBP6)

Guanylate-binding proteins, such as GBP6, are induced by interferon and hydrolyze GTP to both GDP and GMP.Olszewski et al. (2006) identified GBP6 within the GBP gene cluster on chromosome 1. The 634-amino acid GBP6 protein shares 74% identity with both GBP7 and GBP4. All GBPs, including GBP6, have a conserved N-terminal globular GTP-binding domain containing 2 consensus sequences and a third T(L/V)RD sequence not found in other GTPases.GBP6 lacks a C-terminal CaaX isoprenylation motif found in GBP1, GBP2, and GBP5 . EST database analysis indicated that GBP6 expression was limited to larynx, muscle, and tongue.Using RT-PCR, Tripal et al. (2007) detected expression of all GBPs except GBP6 and GBP7 in endothelial cells after stimulation with IFNG, TNF, or IL1B.