Systematic Analysis of Human Protein Complexes Identifies Chromosome Segregation Proteins

Research Institute of Molecular Pathology (IMP), Dr. Bohr-Gasse 7, A-1030 Vienna, Austria.
Science (Impact Factor: 33.61). 04/2010; 328(5978):593-9. DOI: 10.1126/science.1181348
Source: PubMed


Chromosome segregation and cell division are essential, highly ordered processes that depend on numerous protein complexes.
Results from recent RNA interference screens indicate that the identity and composition of these protein complexes is incompletely
understood. Using gene tagging on bacterial artificial chromosomes, protein localization, and tandem-affinity purification–mass
spectrometry, the MitoCheck consortium has analyzed about 100 human protein complexes, many of which had not or had only incompletely
been characterized. This work has led to the discovery of previously unknown, evolutionarily conserved subunits of the anaphase-promoting
complex and the γ-tubulin ring complex—large complexes that are essential for spindle assembly and chromosome segregation.
The approaches we describe here are generally applicable to high-throughput follow-up analyses of phenotypic screens in mammalian

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    • "Multiple copies of the γ-TuSC associate with GCP4, GCP5 and GCP6 and this association contributes to formation of the characteristic structure of the γ-TuRC. Several other proteins including MOZART1, MOZART2 (or GCP8) and NEDD1 (also called GCP-WD or GCP7) have also been described as components of the human γ-TuRC but they might have a regulatory rather than a structural role [13–15]. "
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    • "RAD5226), chromosome maintenance (cf. Sir4p27) and centrosome control28 (cf. Cenp-F29). "
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    • "Initially created to record the effects of human gene knockdowns on chromosome behavior during the cell cycle (Neumann et al., 2010), this resource is being complemented by data sets from subsequent RNAi screens investigating additional cellular processes. Also included are data on the subcellular localization and protein interactions of gene products required for cell division (Hutchins et al., 2010). The MitoCheck database can be searched using human gene symbols, synonyms, or UniProt IDs, plus gene terms for orthologous nonhuman genes, making this a unique and valuable cross-species functional resource. "
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