title: Characterization of human septin interactions.
abstract: Septins constitute a group of GTP binding proteins that assemble into homo- and hetero-oligomeric complexes and filaments. These higher order septin structures are thought to function like scaffolds and/or diffusion barriers serving as spatial localizers for many proteins with key roles in cell polarity and cell cycle progression. In this study, we extensively characterized septin interaction partners using yeast two-hybrid and three-hybrid systems in addition to precipitation analyses in platelets. As a result, we identified human hetero-trimeric septin complexes on a large scale, which had been only postulated in the past. In addition, we illustrated roles of SEPT9 that might contribute to hetero-trimeric septin complex formation. SEPT9 can substitute for septins of the SEPT2 group and partially for SEPT7. Mutagenic analyses revealed that mutation of a potential phosphorylation site in SEPT7 (Y318) regulates the interaction with other septins. We identified several septin-septin interactions in platelets suggesting a regulatory role of diverse septin complexes in platelet function.
authors.affiliation: Department of Pediatrics and Adolescent Medicine, University Medical Center Freiburg, Freiburg, Germany.
authors.forename: Kirstin
authors.initials: K
authors.lastname: Sandrock
authors.forename: Ingrid
authors.initials: I
authors.lastname: Bartsch
authors.forename: Susanne
authors.initials: S
authors.lastname: Bläser
authors.forename: Anja
authors.initials: A
authors.lastname: Busse
authors.forename: Eileen
authors.initials: E
authors.lastname: Busse
authors.forename: Barbara
authors.initials: B
authors.lastname: Zieger
mesh_terms: D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D010766:Phosphorylation; D011485:Protein Binding; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism*; D058112:Septins / Q000235:genetics / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
chemical_list: D018797:Cell Cycle Proteins; D020033:Protein Isoforms; C000602252:SEPTIN2 protein, human; C113158:SEPTIN7 protein, human; C474315:SEPTIN9 protein, human; D058112:Septins