title: Structural basis for recruitment of mitochondrial fission complexes by Fis1.
abstract: Mitochondrial fission controls mitochondrial shape and physiology, including mitochondrial remodeling in apoptosis. During assembly of the yeast mitochondrial fission complex, the outer membrane protein Fis1 recruits the dynamin-related GTPase Dnm1 to mitochondria. Fis1 contains a tetratricopeptide repeat (TPR) domain and interacts with Dnm1 via the molecular adaptors Mdv1 and Caf4. By using crystallographic analysis of adaptor-Fis1 complexes, we show that these adaptors use two helices to bind to both the concave and convex surfaces of the Fis1 TPR domain. Fis1 therefore contains two interaction interfaces, a binding mode that, to our knowledge, has not been observed previously for TPR domains. Genetic and biochemical studies indicate that both binding interfaces are important for binding of Mdv1 and Caf4 to Fis1 and for mitochondrial fission activity in vivo. Our results reveal how Fis1 recruits the mitochondrial fission complex and will facilitate efforts to manipulate mitochondrial fission.
authors.affiliation: Division of Biology, California Institute of Technology, 1200 East California Boulevard, MC 114-96, Pasadena, CA 91125, USA.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.forename: David C
authors.initials: DC
authors.lastname: Chan
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D020816:Amino Acid Motifs; D001665:Binding Sites; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018360:Crystallography, X-Ray; D008024:Ligands; D008928:Mitochondria / Q000737:chemistry / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D011485:Protein Binding; D020836:Protein Structure, Quaternary; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C519559:Caf4 protein, S cerevisiae; D002352:Carrier Proteins; C464859:FIS1 protein, S cerevisiae; D008024:Ligands; C429283:MDV1 protein, S cerevisiae; D024101:Mitochondrial Proteins; D029701:Saccharomyces cerevisiae Proteins