Faculty Opinions recommendation of The role of the histone H3 variant CENPA in prostate cancer.

Abstract The centromere is a chromosome locus that directs equal segregation of chromosomes during cell division. A nucleosome containing the histone H3 variant CENP-A epigenetically defines the centromere. Here, we summarize findings from recent structural biology studies, including several CryoEM structures, that contributed to elucidate specific features of the CENP-A nucleosome and molecular determinants of its interactions with CENP-C and CENP-N, the only two centromere proteins that directly bind to it. Based on those findings, we propose a role of the CENP-A nucleosome in the organization of centromeric chromatin beyond binding centromeric proteins.

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N-terminal sumoylation of centromeric histone H3 variant Cse4 regulates its proteolysis to prevent mislocalization to non-centromeric chromatin

10.1101/176206 ◽

2017 ◽

Cited By ~ 1

Author(s):

Kentaro Ohkuni ◽

Reuben Levy-Myers ◽

Jack Warren ◽

Wei-Chun Au ◽

Yoshimitsu Takahashi ◽

...

Keyword(s):

Genome Stability ◽

Histone H3 ◽

Physiological Role ◽

Centromeric Chromatin ◽

E3 Ligases ◽

Physiological Conditions ◽

Evolutionarily Conserved ◽

Histone H3 Variant

AbstractStringent regulation of cellular levels of evolutionarily conserved centromeric histone H3 variant (CENP-A in humans, CID in flies, Cse4 in yeast) prevents its mislocalization to non-centromeric chromatin. Overexpression and mislocalization of CENP-A has been observed in cancers and leads to aneuploidy in yeast, flies, and human cells. Ubiquitin-mediated proteolysis of Cse4 by E3 ligases such as Psh1 and Sumo-Targeted Ubiquitin Ligase (STUbL) Slx5 prevent mislocalization of Cse4. Previously, we identified Siz1 and Siz2 as the major E3 ligases for sumoylation of Cse4. In this study, we identify lysine 65 (K65) in Cse4 as a SUMO site and show that sumoylation of Cse4 K65 regulates its ubiquitin-mediated proteolysis by Slx5. Strains expressing cse4 K65R exhibit reduced levels of sumoylated and ubiquitinated Cse4 in vivo. Furthermore, co-immunoprecipitation experiments reveal reduced interaction of cse4 K65R with Slx5. Defects in sumoylation of cse4 K65R contribute to increased stability and mislocalization of cse4 K65R under normal physiological conditions. Based on the increased stability of cse4 K65R in psh1∆ strains but not in slx5∆ strains, we conclude that Slx5 targets sumoylated Cse4 K65 for ubiquitination-mediated proteolysis independent of Psh1. In summary, we have identified and characterized the physiological role of Cse4 sumoylation and determined that sumoylation of Cse4 K65 regulates ubiquitin-mediated proteolysis and prevents mislocalization of Cse4 which is required for genome stability.

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A Novel Role of the N Terminus of Budding Yeast Histone H3 Variant Cse4 in Ubiquitin-Mediated Proteolysis

Genetics ◽

10.1534/genetics.113.149898 ◽

2013 ◽

Vol 194 (2) ◽

pp. 513-518 ◽

Cited By ~ 43

Author(s):

Wei Chun Au ◽

Anthony R. Dawson ◽

David W. Rawson ◽

Sara B. Taylor ◽

Richard E. Baker ◽

...

Keyword(s):

Budding Yeast ◽

Histone H3 ◽

N Terminus ◽

Histone H3 Variant

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Epigenetic inheritance of centromere identity in a heterologous system

10.1101/560391 ◽

2019 ◽

Cited By ~ 2

Author(s):

Virginie Roure ◽

Bethan Medina-Pritchard ◽

Eduard Anselm ◽

A. Arockia Jeyaprakash ◽

Patrick Heun

Keyword(s):

Chromosome Segregation ◽

Chromosomal Region ◽

Histone H3 ◽

Epigenetic Inheritance ◽

Centromeric Chromatin ◽

Centromere Proteins ◽

Heterologous System ◽

Histone H3 Variant ◽

Self Association

SUMMARYThe centromere is an essential chromosomal region required for accurate chromosome segregation. Most eukaryotic centromeres are defined epigenetically by the histone H3 variant, CENP-A, yet how its self-propagation is achieved remains poorly understood. Here we developed a heterologous system to reconstitute epigenetic inheritance of centromeric chromatin by ectopically targeting the Drosophila centromere proteins dCENP-A, dCENP-C and CAL1 to LacO arrays in human cells. Dissecting the function of these three components uncovers the key role of self-association of dCENP-C and CAL1 for their mutual interaction and dCENP-A deposition. Importantly, we identify the components required for dCENP-C loading onto chromatin, involving a cooperation between CAL1 and dCENP-A nucleosomes, thus closing the epigenetic loop to ensure dCENP-C and dCENP-A replenishment during the cell division cycle. Finally, we show that all three Drosophila factors are sufficient for dCENP-A propagation and propose a model for the epigenetic inheritance of centromere identity.

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The ATAD2/ANCCA homolog Yta7 cooperates with Scm3HJURP to deposit Cse4CENP-A at the centromere in yeast

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1917814117 ◽

2020 ◽

Vol 117 (10) ◽

pp. 5386-5393 ◽

Cited By ~ 2

Author(s):

Sara Shahnejat-Bushehri ◽

Ann E. Ehrenhofer-Murray

Keyword(s):

Saccharomyces Cerevisiae ◽

Chromosome Segregation ◽

Histone H3 ◽

Nucleosome Assembly ◽

Direct Role ◽

Kinetochore Assembly ◽

Histone H3 Variant ◽

Assembly Factor

The AAA+ ATPase and bromodomain factor ATAD2/ANCCA is overexpressed in many types of cancer, but how it contributes to tumorigenesis is not understood. Here, we report that the Saccharomyces cerevisiae homolog Yta7ATAD2 is a deposition factor for the centromeric histone H3 variant Cse4CENP-A at the centromere in yeast. Yta7ATAD2 regulates the levels of centromeric Cse4CENP-A in that yta7∆ causes reduced Cse4CENP-A deposition, whereas YTA7 overexpression causes increased Cse4CENP-A deposition. Yta7ATAD2 coimmunoprecipitates with Cse4CENP-A and is associated with the centromere, arguing for a direct role of Yta7ATAD2 in Cse4CENP-A deposition. Furthermore, increasing centromeric Cse4CENP-A levels by YTA7 overexpression requires the activity of Scm3HJURP, the centromeric nucleosome assembly factor. Importantly, Yta7ATAD2 interacts in vivo with Scm3HJURP, indicating that Yta7ATAD2 is a cochaperone for Scm3HJURP. The absence of Yta7 causes defects in growth and chromosome segregation with mutations in components of the inner kinetochore (CTF19/CCAN, Mif2CENP-C, Cbf1). Since Yta7ATAD2 is an AAA+ ATPase and potential hexameric unfoldase, our results suggest that it may unfold the Cse4CENP-A histone and hand it over to Scm3HJURP for subsequent deposition in the centromeric nucleosome. Furthermore, our findings suggest that ATAD2 overexpression may enhance malignant transformation in humans by misregulating centromeric CENP-A levels, thus leading to defects in kinetochore assembly and chromosome segregation.

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The role of heterochromatin in centromere function

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2004.1611 ◽

2005 ◽

Vol 360 (1455) ◽

pp. 569-579 ◽

Cited By ~ 100

Author(s):

Alison L Pidoux ◽

Robin C Allshire

Keyword(s):

Fission Yeast ◽

Histone H3 ◽

Centromeric Heterochromatin ◽

Chromatin Domain ◽

Heterochromatin Protein 1 ◽

Heterochromatin Protein ◽

Centromere Function ◽

Kinetochore Assembly ◽

Histone H3 Variant

Chromatin at centromeres is distinct from the chromatin in which the remainder of the genome is assembled. Two features consistently distinguish centromeres: the presence of the histone H3 variant CENP-A and, in most organisms, the presence of heterochromatin. In fission yeast, domains of silent ‘heterochromatin’ flank the CENP-A chromatin domain that forms a platform upon which the kinetochore is assembled. Thus, fission yeast centromeres resemble their metazoan counterparts where the kinetochore is embedded in centromeric heterochromatin. The centromeric outer repeat chromatin is underacetylated on histones H3 and H4, and methylated on lysine 9 of histone H3, which provides a binding site for the chromodomain protein Swi6 (orthologue of Heterochromatin Protein 1, HP1). The remarkable demonstration that the assembly of repressive heterochromatin is dependent on the RNA interference machinery provokes many questions about the mechanisms of this process that may be tractable in fission yeast. Heterochromatin ensures that a high density of cohesin is recruited to centromeric regions, but it could have additional roles in centromere architecture and the prevention of merotely, and it might also act as a trigger for kinetochore assembly. In addition, we discuss an epigenetic model for ensuring that CENP-A is targeted and replenished at the kinetochore domain.

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Arabidopsis MZT1 homologs GIP1 and GIP2 are essential for centromere architecture

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1506351112 ◽

2015 ◽

Vol 112 (28) ◽

pp. 8656-8660 ◽

Cited By ~ 32

Author(s):

Morgane Batzenschlager ◽

Inna Lermontova ◽

Veit Schubert ◽

Jörg Fuchs ◽

Alexandre Berr ◽

...

Keyword(s):

Chromosome Segregation ◽

Histone H3 ◽

Genome Integrity ◽

Interacting Proteins ◽

Central Function ◽

Chromatid Cohesion ◽

Histone H3 Variant ◽

Complex Protein ◽

Cohesin Subunit

Centromeres play a pivotal role in maintaining genome integrity by facilitating the recruitment of kinetochore and sister-chromatid cohesion proteins, both required for correct chromosome segregation. Centromeres are epigenetically specified by the presence of the histone H3 variant (CENH3). In this study, we investigate the role of the highly conserved γ-tubulin complex protein 3-interacting proteins (GIPs) in Arabidopsis centromere regulation. We show that GIPs form a complex with CENH3 in cycling cells. GIP depletion in the gip1gip2 knockdown mutant leads to a decreased CENH3 level at centromeres, despite a higher level of Mis18BP1/KNL2 present at both centromeric and ectopic sites. We thus postulate that GIPs are required to ensure CENH3 deposition and/or maintenance at centromeres. In addition, the recruitment at the centromere of other proteins such as the CENP-C kinetochore component and the cohesin subunit SMC3 is impaired in gip1gip2. These defects in centromere architecture result in aneuploidy due to severely altered centromeric cohesion. Altogether, we ascribe a central function to GIPs for the proper recruitment and/or stabilization of centromeric proteins essential in the specification of the centromere identity, as well as for centromeric cohesion in somatic cells.

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The role of the histone H3 variant CENPA in prostate cancer

Journal of Biological Chemistry ◽

10.1074/jbc.ra119.010080 ◽

2020 ◽

Vol 295 (25) ◽

pp. 8537-8549 ◽

Cited By ~ 3

Author(s):

Anjan K. Saha ◽

Rafael Contreras-Galindo ◽

Yashar S. Niknafs ◽

Matthew Iyer ◽

Tingting Qin ◽

...

Keyword(s):

Prostate Cancer ◽

Cell Biology ◽

Protein A ◽

Histone H3 ◽

Cancer Cell Line ◽

Disease Stage ◽

Epigenetic Mark ◽

Loss Of Function ◽

Chip Sequencing ◽

Histone H3 Variant

Overexpression of centromeric proteins has been identified in a number of human malignancies, but the functional and mechanistic contributions of these proteins to disease progression have not been characterized. The centromeric histone H3 variant centromere protein A (CENPA) is an epigenetic mark that determines centromere identity. Here, using an array of approaches, including RNA-sequencing and ChIP-sequencing analyses, immunohistochemistry-based tissue microarrays, and various cell biology assays, we demonstrate that CENPA is highly overexpressed in prostate cancer in both tissue and cell lines and that the level of CENPA expression correlates with the disease stage in a large cohort of patients. Gain-of-function and loss-of-function experiments confirmed that CENPA promotes prostate cancer cell line growth. The results from the integrated sequencing experiments suggested a previously unidentified function of CENPA as a transcriptional regulator that modulates expression of critical proliferation, cell-cycle, and centromere/kinetochore genes. Taken together, our findings show that CENPA overexpression is crucial to prostate cancer growth.

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