Chromosome Condensation Factor Brn1p Is Required for Chromatid Separation in Mitosis

Ouspenski, Ilia I.; Cabello, Olga A.; Brinkley, B. R.

doi:10.1091/mbc.11.4.1305

Cited by 100 publications

(101 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It can be speculated that impaired association of condensation factors on hyperacetylated chromatin may alter the dissociation of cohesins during early mitotic stages, resulting in persistent cohesion along chromatid arms. The separin-dependent release of centromeric cohesins at anaphase onset would promote the formation of chromatin bridges between sister chromatids due to poor sister chromatid arm resolution, as already reported for condensin mutants (Bhat et al, 1996;Ouspenski et al, 2000, Steffensen et al, 2001 or after inhibition of sister chromatid decatenation by topoisomerase II inhibitors (Cimini et al, 1997). On the other hand, a lack of sister chromatid separation at the centromere level is clearly indicated by the observation of chromatin bridges spanning the centromeric region.…”

Section: Histone Hyperacetylation Prevents Sister Chromatid Resolutiosupporting

confidence: 64%

Histone Hyperacetylation in Mitosis Prevents Sister Chromatid Separation and Produces Chromosome Segregation Defects

Cimini

Mattiuzzo

Torosantucci

et al. 2003

MBoC

169

160

View full text Add to dashboard Cite

Posttranslational modifications of core histones contribute to driving changes in chromatin conformation and compaction. Herein, we investigated the role of histone deacetylation on the mitotic process by inhibiting histone deacetylases shortly before mitosis in human primary fibroblasts. Cells entering mitosis with hyperacetylated histones displayed altered chromatin conformation associated with decreased reactivity to the anti-Ser 10 phospho H3 antibody, increased recruitment of protein phosphatase 1-δ on mitotic chromosomes, and depletion of heterochromatin protein 1 from the centromeric heterochromatin. Inhibition of histone deacetylation before mitosis produced defective chromosome condensation and impaired mitotic progression in living cells, suggesting that improper chromosome condensation may induce mitotic checkpoint activation. In situ hybridization analysis on anaphase cells demonstrated the presence of chromatin bridges, which were caused by persisting cohesion along sister chromatid arms after centromere separation. Thus, the presence of hyperacetylated chromatin during mitosis impairs proper chromosome condensation during the pre-anaphase stages, resulting in poor sister chromatid resolution. Lagging chromosomes consisting of single or paired sisters were also induced by the presence of hyperacetylated histones, indicating that the less constrained centromeric organization associated with heterochromatin protein 1 depletion may promote the attachment of kinetochores to microtubules coming from both poles

show abstract

Section: Histone Hyperacetylation Prevents Sister Chromatid Resolutiosupporting

confidence: 64%

Histone Hyperacetylation in Mitosis Prevents Sister Chromatid Separation and Produces Chromosome Segregation Defects

Cimini

Mattiuzzo

Torosantucci

et al. 2003

MBoC

169

160

View full text Add to dashboard Cite

show abstract

“…Similar complexes exist in higher eukaryotes (Hirano et al, 1997;Schmiesing et al, 1998;Sutani et al, 1999;Freeman et al, 2000;Kimura et al, 2001). Dysfunction of any condensin subunit results in impaired mitotic and meiotic chromosome segregation (Strunnikov et al, 1995;Bhat et al, 1996;Freeman et al, 2000;Ouspenski et al, 2000;Hagstrom et al, 2002;Hudson et al, 2003;Ono et al, 2003;Cobbe et al, 2006).…”

Section: Introductionmentioning

confidence: 88%

Transcriptional homogenization of rDNA repeats in the episome-based nucleolus induces genome-wide changes in the chromosomal distribution of condensin

Wang

Strunnikov

2008

Plasmid

View full text Add to dashboard Cite

Condensin activity establishes and maintains mitotic chromosome condensation, however the mechanisms of condensin recognition of specific chromosomal sites remain unknown. rDNA is the chief condensin binding locus in S. cerevisiae, and the level of nucleolar transcription is one of the key factors determining condensin loading to the nucleolar organizer. A new aspect of this transcriptional control is demonstrated in cells with a diffuse (episomal) nucleolar organizer, where active transcription excludes condensin from the transcribed regions of rDNA. Genome-wide ChIPchip analysis showed that these cells acquire an altered and a more robust pattern of chromosomal condensin distribution, with increased enrichment of wild-type hotspots and with emergence of new sites, most notably in the subtelomeric regions. This genome-wide condensin relocalization induced by the increase in rDNA transcription and, possibly, nucleolar architecture uncovers a novel potential role of the nucleolus in the general chromosome organization.

show abstract

“…Condensin complexes are structural components of mitotic chromosomes and play a central role in driving chromosome condensation Sutani et al, 1999;Ouspenski et al, 2000). In the Xenopus egg extract model the 13S condensin complex is required for ATP-dependent chromatin condensation .…”

Section: Introductionmentioning

confidence: 99%

“…Although all three 11S subunits are required for proper chromosome condensation and chromatid segregation (Sutani et al, 1999;Freeman et al, 2000;Lavoie et al, 2000;Ouspenski et al, 2000), the specific roles of each of the non-SMC subunits remain to be identified (Kimura and Hirano, 2000). Recently, Kimura and Hirano (2000) have proposed that XCAP-D2 and XCAP-G may participate in the activation of the XCAP-E and XCAP-C ATPases by a process directly involving their HEAT domains or by modifying the conformation of the SMC heterodimer.…”

Section: Introductionmentioning

confidence: 99%

“…This effect was attributed to barren protein association with topoisomerase II (topoII) and its modulation of topoII activity in vitro. However, in S. cerevisiae the barren homologue Brn1p is required for chromatid condensation (Lavoie et al, 2000;Ouspenski et al, 2000) but does not appear to influence topo II activity (Ouspenski, unpublished results;Lavoie et al, 2000). Surprisingly, in Drosophila SMC4 mutants, chromosome condensation does not appear to be affected as indicated by normal compaction of the longitudinal axis during mitosis.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Cell Cycle-dependent Expression and Nucleolar Localization of hCAP-H

Cabello¹,

Eliseeva

He³

et al. 2001

MBoC

Self Cite

View full text Add to dashboard Cite

Condensin is a conserved 13S heteropentamer composed of two nonidentical structural maintenance of chromosome (SMC) family proteins, in Xenopus XCAP-C and XCAP-E, and three regulatory subunits, XCAP-D2, XCAP-G, and XCAP-H. Both biochemical and genetic analyses have demonstrated an essential role for the 13S condensin complex in mitotic chromosome condensation. Further, a potential requirement for condensin in completion of chromatid arm separation in early anaphase is demonstrated by the mutational phenotypes of the Drosophila homologues of XCAP-H, barren and XCAP-C, DmSMC4. In this study we have investigated the expression and subcellular distribution of hCAP-H, the human homolog of XCAP-H, in order to better understand its cellular functions. Transcription of hCAP-H was restricted to proliferating cells with highest expression during the G 2 phase of the cell cycle. In contrast, cellular hCAP-H protein levels were constant throughout the cell cycle. hCAP-H was found to be associated with mitotic chromosomes exhibiting a nonuniform but symmetric distribution along sister chromatids. The symmetry of hCAP-H association with sister chromatids suggests that there are sequence-dependent domains of condensin aggregation. During interphase hCAP-H, -C, and -E, have distinct punctate nucleolar localization, suggesting that condensin may associate with and modulate the conformation and function of rDNA. hCAP-H association with condensed chromatin was not observed in the early phase of chromosome condensation when histone H3 phosphorylation has already taken place. This finding is consistent with the hypothesis that histone H3 phosphorylation precedes condensin-mediated condensation.

show abstract

Chromosome Condensation Factor Brn1p Is Required for Chromatid Separation in Mitosis

Cited by 100 publications

References 28 publications

Histone Hyperacetylation in Mitosis Prevents Sister Chromatid Separation and Produces Chromosome Segregation Defects

Histone Hyperacetylation in Mitosis Prevents Sister Chromatid Separation and Produces Chromosome Segregation Defects

Transcriptional homogenization of rDNA repeats in the episome-based nucleolus induces genome-wide changes in the chromosomal distribution of condensin

Cell Cycle-dependent Expression and Nucleolar Localization of hCAP-H

Contact Info

Product

Resources

About