title: Subunit composition, protein interactions, and structures of the mammalian brain sec6/8 complex and septin filaments.
abstract: Both the sec6/8 complex and septin filaments have been implicated in directing vesicles and proteins to sites of active membrane addition in yeast. The rat brain sec6/8 complex coimmunoprecipitates with a filament composed of four mammalian septins, suggesting an interaction between these complexes. One of the septins, CDC10, displays broad subcellular and tissue distributions and is found in postmitotic neurons as well as dividing cells. Electron microscopic studies showed that the purified rat brain septins form filaments of 8.25 nm in diameter; the lengths of the filaments are multiples of 25 nm. Glutaraldehyde-fixed rat brain sec6/8 complex adopts a conformation resembling the letter "T" or "Y". The sec6/8 and septin complexes likely play an important role in trafficking vesicles and organizing proteins at the plasma membrane of neurons.
authors.affiliation: Howard Hughes Medical Institute, Department of Molecular and Cellular Physiology, Stanford University School of Medicine, California 94305, USA.
authors.forename: S C
authors.initials: SC
authors.lastname: Hsu
authors.forename: C D
authors.initials: CD
authors.lastname: Hazuka
authors.forename: R
authors.initials: R
authors.lastname: Roth
authors.forename: D L
authors.initials: DL
authors.lastname: Foletti
authors.forename: J
authors.initials: J
authors.lastname: Heuser
authors.forename: R H
authors.initials: RH
authors.lastname: Scheller
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies; D001923:Brain Chemistry / Q000502:physiology*; D002352:Carrier Proteins / Q000032:analysis / Q000378:metabolism* / Q000648:ultrastructure; D018797:Cell Cycle Proteins / Q000032:analysis / Q000276:immunology; D002478:Cells, Cultured; D003598:Cytoskeletal Proteins; D005613:Freeze Etching; D020558:GTP Phosphohydrolases; D006624:Hippocampus / Q000166:cytology; D008565:Membrane Proteins; D051379:Mice; D008807:Mice, Inbred BALB C; D008840:Microfilament Proteins / Q000032:analysis / Q000378:metabolism* / Q000648:ultrastructure; D008969:Molecular Sequence Data; D011817:Rabbits; D051381:Rats; D029702:Schizosaccharomyces pombe Proteins; D058112:Septins; D013154:Spleen / Q000166:cytology; D013572:Synaptic Vesicles / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure; D014157:Transcription Factors; D033921:Vesicular Transport Proteins
chemical_list: D000906:Antibodies; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D003598:Cytoskeletal Proteins; C490685:EXOC3 protein, human; C489607:EXOC4 protein, human; C096102:Exoc3 protein, rat; C076326:Exoc4 protein, rat; D008565:Membrane Proteins; D008840:Microfilament Proteins; D029702:Schizosaccharomyces pombe Proteins; C490683:Sec6l1 protein, mouse; C489608:Sec8l1 protein, mouse; D014157:Transcription Factors; D033921:Vesicular Transport Proteins; C061178:cdc10 protein, S pombe; D020558:GTP Phosphohydrolases; C113158:SEPTIN7 protein, human; C512895:Sept7 protein, mouse; C512894:Septin7 protein, rat; D058112:Septins