Identification of Xenopus SMC protein complexes required for sister chromatid cohesion

Losada, A., Hirano, M., Hirano, T. (July 1998) Identification of Xenopus SMC protein complexes required for sister chromatid cohesion. Genes and Development , 12 (13). pp. 1986-97. ISSN 0890-9369 (Print)

[thumbnail of Hirano_GenesDev1998.pdf]

Download (922kB) | Preview
DOI: 10.1101/gad.12.13.1986


The structural maintenance of chromosomes (SMC) family is a growing family of chromosomal ATPases. The founding class of SMC protein complexes, condensins, plays a central role in mitotic chromosome condensation. We report here a new class of SMC protein complexes containing XSMC1 and XSMC3, Xenopus homologs of yeast Smc1p and Smc3p, respectively. The protein complexes (termed cohesins) exist as two major forms with sedimentation coefficients of 9S and 14S. 9S cohesin is a heterodimer of XSMC1 and XSMC3, whereas 14S cohesin contains three additional subunits. One of them has been identified as a Xenopus homolog of the Schizosaccharomyces pombe Rad21p implicated in DNA repair and the Saccharomyces cerevisiae Scc1p/Mcd1p implicated in sister chromatid cohesion. 14S cohesin binds to interphase chromatin independently of DNA replication and dissociates from it at the onset of mitosis. Immunodepletion of cohesins during interphase causes defects in sister chromatid cohesion in subsequent mitosis, whereas condensation is unaffected. These results suggest that proper assembly of mitotic chromosomes is regulated by two distinct classes of SMC protein complexes, cohesins and condensins.

Item Type: Paper
Uncontrolled Keywords: Adenosinetriphosphatase/genetics/physiology Amino Acid Sequence Animals Cell Cycle Proteins/genetics/ isolation & purification/physiology Chromatids/genetics/ physiology Chromatin/metabolism Chromosomal Proteins, Non-Histone Cloning, Molecular DNA Replication/genetics DNA-Binding Proteins/genetics/ isolation & purification/physiology Fungal Proteins/genetics Interphase/genetics Macromolecular Substances Mitosis/genetics Molecular Sequence Data Molecular Weight Multiprotein Complexes Nuclear Envelope/genetics Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. Sequence Homology, Amino Acid Xenopus Proteins Xenopus laevis
Subjects: bioinformatics > genomics and proteomics > small molecules > ATP
organs, tissues, organelles, cell types and functions > cell types and functions > cell functions > cell cycle
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > DNA, RNA structure, function, modification > chromatid
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > protein structure, function, modification > protein types > DNA binding protein
organs, tissues, organelles, cell types and functions > organelles, types and functions > mitosis
organism description > animal > Frog > xenopus
CSHL Authors:
Communities: CSHL labs > Hirano lab
Depositing User: Kathleen Darby
Date: 1 July 1998
Date Deposited: 01 May 2014 16:39
Last Modified: 01 May 2014 16:39
PMCID: PMC316973
Related URLs:

Actions (login required)

Administrator's edit/view item Administrator's edit/view item
CSHL HomeAbout CSHLResearchEducationNews & FeaturesCampus & Public EventsCareersGiving