title: GTP-dependent scaffold formation in the GTPase of Immunity Associated Protein family.
abstract: GTP ases of Immunity-Associated Proteins (GIMAPs) are a family of guanine nucleotide binding (G) proteins which are implicated in the regulation of apoptosis in lymphocytes. GIMAPs are composed of an amino-terminal G domain and carboxy-terminal extensions of varying size. Our recent biochemical and structural analysis of a representative GIMAP family member, GIMAP2, revealed the molecular basis of GTP-dependent oligomerization which involves two interfaces in the G domain. Whereas the amphipathic helix α7 in the C-terminal extension closely folds against the G domain in the GDP-bound state, it might be released in the GTP-bound state to assemble interaction partners. We also showed that the GIMAP2 oligomer functions at the surface of lipid droplets in a Jurkat T cell line. Here, we review our recent work and discuss the GIMAP2 oligomer as a GTP-dependent protein scaffold at the surface of lipid droplets controlling apoptosis.
authors.affiliation: Max-Delbrück-Centrum für Molekulare Medizin; Freie Universität Berlin.
authors.forename: David
authors.initials: D
authors.lastname: Schwefel
authors.forename: Oliver
authors.initials: O
authors.lastname: Daumke