title: Molecular architecture of SMC proteins and the yeast cohesin complex.
abstract: Sister chromatids are held together by the multisubunit cohesin complex, which contains two SMC (Smc1 and Smc3) and two non-SMC (Scc1 and Scc3) proteins. The crystal structure of a bacterial SMC "hinge" region along with EM studies and biochemical experiments on yeast Smc1 and Smc3 proteins show that SMC protamers fold up individually into rod-shaped molecules. A 45 nm long intramolecular coiled coil separates the hinge region from the ATPase-containing "head" domain. Smc1 and Smc3 bind to each other via heterotypic interactions between their hinges to form a V-shaped heterodimer. The two heads of the V-shaped dimer are connected by different ends of the cleavable Scc1 subunit. Cohesin therefore forms a large proteinaceous loop within which sister chromatids might be entrapped after DNA replication.
authors: Research Institute of Molecular Pathology, Dr. Bohr Gasse 7, A-1030 Vienna, Austria.
authors: Christian H
authors: CH
authors: Haering
authors: Jan
authors: J
authors: Löwe
authors: Andreas
authors: A
authors: Hochwagen
authors: Kim
authors: K
authors: Nasmyth
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry; D001426:Bacterial Proteins / Q000737:chemistry; D018797:Cell Cycle Proteins / Q000737:chemistry*; D011508:Chondroitin Sulfate Proteoglycans; D002842:Chromatids / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000737:chemistry*; D004261:DNA Replication; D019281:Dimerization; D005057:Eukaryotic Cells / Q000378:metabolism; D005656:Fungal Proteins / Q000737:chemistry*; D046911:Macromolecular Substances; D008954:Models, Biological; D008958:Models, Molecular; D009687:Nuclear Proteins / Q000737:chemistry*; D010750:Phosphoproteins; D011387:Prokaryotic Cells / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D025941:Protein Interaction Mapping; D017434:Protein Structure, Tertiary; D021122:Protein Subunits; D011993:Recombinant Fusion Proteins / Q000737:chemistry; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry*; D013329:Structure-Activity Relationship; D020124:Thermotoga maritima / Q000737:chemistry; D014961:X-Ray Diffraction; D000097722:Cohesins; D000098550:Structural Maintenance of Chromosome Protein 1
chemical_list: D000251:Adenosine Triphosphatases; D001426:Bacterial Proteins; D018797:Cell Cycle Proteins; D011508:Chondroitin Sulfate Proteoglycans; D002868:Chromosomal Proteins, Non-Histone; D005656:Fungal Proteins; D046911:Macromolecular Substances; D009687:Nuclear Proteins; D010750:Phosphoproteins; D021122:Protein Subunits; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D000097722:Cohesins; D000098550:Structural Maintenance of Chromosome Protein 1; C490529:MCD1 protein, S cerevisiae; C120372:SMC3 protein, S cerevisiae