Two Human Orthologues of Eco1/Ctf7 Acetyltransferases Are Both Required for Proper Sister-Chromatid Cohesion

Genetic studies in yeast and Drosophila have uncovered a conserved acetyltransferase involved in sister-chromatid cohesion. Here, we described the two human orthologues, previously named EFO1/ESCO1 and EFO2/ESCO2. Similar to their yeast (Eco1/Ctf7 and Eso1) and fly (deco) counterparts, both proteins feature a conserved C-terminal domain consisting of a H2C2 zinc finger motif and an acetyltransferase domain that is able to catalyze autoacetylation reaction in vitro. However, no similarity can be detected outside of the conserved domain. RNA interference depletion experiment revealed that EFO1/ESCO1 and EFO2/ESCO2 were not redundant and that both were required for proper sister-chromatid cohesion. The difference between EFO1 and EFO2 also is reflected in their cell cycle regulation. In mitosis, EFO1 is phosphorylated, whereas EFO2 is degraded. Furthermore, both proteins associate with chromosomes, and the chromosome binding depends on the diverse N-terminal domains. We propose that EFO1 and EFO2 are targeted to different chromosome structures to help establish or maintain sister-chromatid cohesion.

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The acetyltransferase activity of San stabilizes the mitotic cohesin at the centromeres in a shugoshin-independent manner

The Journal of Cell Biology ◽

10.1083/jcb.200701043 ◽

2007 ◽

Vol 177 (4) ◽

pp. 587-597 ◽

Cited By ~ 55

Author(s):

Fajian Hou ◽

Chih-Wen Chu ◽

Xiangduo Kong ◽

Kyoko Yokomori ◽

Hui Zou

Keyword(s):

Cell Cycle ◽

Sister Chromatid ◽

Sister Chromatid Cohesion ◽

Independent Manner ◽

Acetyltransferase Activity ◽

Chromatid Cohesion ◽

Interphase Cells ◽

Gain Access

Proper sister chromatid cohesion is critical for maintaining genetic stability. San is a putative acetyltransferase that is important for sister chromatid cohesion in Drosophila melanogaster, but not in budding yeast. We showed that San is critical for sister chromatid cohesion in HeLa cells, suggesting that this mechanism may be conserved in metazoans. Furthermore, although a small fraction of San interacts with the NatA complex, San appears to mediate cohesion independently. San exhibits acetyltransferase activity in vitro, and its activity is required for sister chromatid cohesion in vivo. In the absence of San, Sgo1 localizes correctly throughout the cell cycle. However, cohesin is no longer detected at the mitotic centromeres. Furthermore, San localizes to the cytoplasm in interphase cells; thus, it may not gain access to chromosomes until mitosis. Moreover, in San-depleted cells, further depletion of Plk1 rescues the cohesion along the chromosome arms, but not at the centromeres. Collectively, San may be specifically required for the maintenance of the centromeric cohesion in mitosis.

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Acetylation of the SUN protein Mps3 by Eco1 regulates its function in nuclear organization

Molecular Biology of the Cell ◽

10.1091/mbc.e11-07-0600 ◽

2012 ◽

Vol 23 (13) ◽

pp. 2546-2559 ◽

Cited By ~ 15

Author(s):

Suman Ghosh ◽

Jennifer M. Gardner ◽

Christine J. Smoyer ◽

Jennifer M. Friederichs ◽

Jay R. Unruh ◽

...

Keyword(s):

Nuclear Membrane ◽

Sister Chromatid ◽

Transmembrane Domain ◽

Nuclear Organization ◽

Spindle Pole Body ◽

Spindle Pole ◽

Sister Chromatid Cohesion ◽

Chromatid Cohesion

The Saccharomyces cerevisiae SUN-domain protein Mps3 is required for duplication of the yeast centrosome-equivalent organelle, the spindle pole body (SPB), and it is involved in multiple aspects of nuclear organization, including telomere tethering and gene silencing at the nuclear membrane, establishment of sister chromatid cohesion, and repair of certain types of persistent DNA double-stranded breaks. How these diverse SUN protein functions are regulated is unknown. Here we show that the Mps3 N-terminus is a substrate for the acetyltransferase Eco1/Ctf7 in vitro and in vivo and map the sites of acetylation to three lysine residues adjacent to the Mps3 transmembrane domain. Mutation of these residues shows that acetylation is not essential for growth, SPB duplication, or distribution in the nuclear membrane. However, analysis of nonacetylatable mps3 mutants shows that this modification is required for accurate sister chromatid cohesion and for chromosome recruitment to the nuclear membrane. Acetylation of Mps3 by Eco1 is one of the few regulatory mechanisms known to control nuclear organization.

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A Potential Role for Human Cohesin in Mitotic Spindle Aster Assembly

Journal of Biological Chemistry ◽

10.1074/jbc.m103364200 ◽

2001 ◽

Vol 276 (50) ◽

pp. 47575-47582 ◽

Cited By ~ 52

Author(s):

Heather C. Gregson ◽

John A. Schmiesing ◽

Jong-Soo Kim ◽

Toshiki Kobayashi ◽

Sharleen Zhou ◽

...

Keyword(s):

Sister Chromatid ◽

Mitotic Spindle ◽

Potential Role ◽

Metaphase Plate ◽

Spindle Pole ◽

Sister Chromatid Cohesion ◽

Cycle Arrest ◽

Spindle Poles ◽

Chromatid Cohesion

The cohesin multiprotein complex containing SMC1, SMC3, Scc3 (SA), and Scc1 (Rad21) is required for sister chromatid cohesion in eukaryotes. Although metazoan cohesin associates with chromosomes and was shown to function in the establishment of sister chromatid cohesion during interphase, the majority of cohesin was found to be off chromosomes and reside in the cytoplasm in metaphase. Despite its dissociation from chromosomes, however, microinjection of an antibody against human SMC1 led to disorganization of the metaphase plate and cell cycle arrest, indicating that human cohesin still plays an important role in metaphase. To address the mitotic function of human cohesin, the subcellular localization of cohesin components was reexamined in human cells. Interestingly, we found that cohesin localizes to the spindle poles during mitosis and interacts with NuMA, a spindle pole-associated factor required for mitotic spindle organization. The interaction with NuMA persists during interphase. Similar to NuMA, a significant amount of cohesin was found to associate with the nuclear matrix. Furthermore, in the absence of cohesin, mitotic spindle asters failed to formin vitro. Our results raise the intriguing possibility that in addition to its well demonstrated function in sister chromatid cohesion, cohesin may be involved in spindle assembly during mitosis.

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ATP dependent DNA transport within cohesin: Scc2 clamps DNA on top of engaged heads while Scc3 promotes entrapment within the SMC-kleisin ring

10.1101/2020.06.03.132233 ◽

2020 ◽

Author(s):

James E Collier ◽

Byung-Gil Lee ◽

Maurici B Roig ◽

Stanislav Yatskevich ◽

Naomi J Petela ◽

...

Keyword(s):

Sister Chromatid ◽

Atp Hydrolysis ◽

Sister Chromatid Cohesion ◽

S Phase ◽

Coiled Coils ◽

Rigorous Proof ◽

Dna Loops ◽

Dna Transport ◽

Chromatid Cohesion

SUMMARYIn addition to extruding DNA loops, cohesin entraps within its SMC-kleisin ring (S-K) individual DNAs during G1 and sister DNAs during S-phase. All three activities require related hook-shaped proteins called Scc2 and Scc3. Using thiol-specific crosslinking we provide rigorous proof of entrapment activity in vitro. Scc2 alone promotes entrapment of DNAs in the E-S and E-K compartments, between ATP-bound engaged heads and the SMC hinge and associated kleisin, respectively. This does not require ATP hydrolysis nor is it accompanied by entrapment within S-K rings, which is a slower process requiring Scc3. Cryo-EM reveals that DNAs transported into E-S/E-K compartments are “clamped” in a sub-compartment created by Scc2’s association with engaged heads whose coiled coils are folded around their elbow. We suggest that clamping may be a recurrent feature of cohesin complexes active in loop extrusion and that this conformation precedes the S-K entrapment required for sister chromatid cohesion.

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Maternal Obesity Enhances Oocyte Chromosome Abnormalities Associated With Aging

10.1101/505511 ◽

2018 ◽

Cited By ~ 1

Author(s):

Yan Yun ◽

Zijie Wei ◽

Neil Hunter

Keyword(s):

Sister Chromatid ◽

Maternal Obesity ◽

Sister Chromatid Cohesion ◽

Chromosome Abnormalities ◽

Obese Mice ◽

Sister Chromatids ◽

Chromatid Cohesion ◽

Metaphase I

Obesity is increasing globally and maternal obesity has adverse effects on pregnancy outcomes and the long-term health of offspring. Maternal obesity has been associated with pregnancy failure through impaired oogenesis and embryogenesis. However, whether maternal obesity causes chromosome abnormalities in oocytes has remained unclear. Here we show that chromosome abnormalities are increased in the oocytes of obese mice and identify weakened sister-chromatid cohesion as the likely cause. Numbers of full-grown follicles retrieved from obese mice were the same as controls and the efficiency of in vitro oocyte maturation remained high. However, chromosome abnormalities presenting in both metaphase-I and metaphase-II were elevated, most prominently the premature separation of sister chromatids. Weakened sister-chromatid cohesion in oocytes from obese mice was manifested both as the terminalization of chiasmata in metaphase-I and as increased separation of sister centromeres in metaphase II. Obesity-associated abnormalities were elevated in older mice implying that maternal obesity exacerbates the deterioration of cohesion seen with advancing age.

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Transport of DNA within cohesin involves clamping on top of engaged heads by Scc2 and entrapment within the ring by Scc3

eLife ◽

10.7554/elife.59560 ◽

2020 ◽

Vol 9 ◽

Cited By ~ 2

Author(s):

James E Collier ◽

Byung-Gil Lee ◽

Maurici Brunet Roig ◽

Stanislav Yatskevich ◽

Naomi J Petela ◽

...

Keyword(s):

Sister Chromatid ◽

Atp Hydrolysis ◽

Sister Chromatid Cohesion ◽

S Phase ◽

Coiled Coils ◽

Rigorous Proof ◽

Dna Loops ◽

Chromatid Cohesion

In addition to extruding DNA loops, cohesin entraps within its SMC-kleisin ring (S-K) individual DNAs during G1 and sister DNAs during S-phase. All three activities require related hook-shaped proteins called Scc2 and Scc3. Using thiol-specific crosslinking we provide rigorous proof of entrapment activity in vitro. Scc2 alone promotes entrapment of DNAs in the E-S and E-K compartments, between ATP-bound engaged heads and the SMC hinge and associated kleisin, respectively. This does not require ATP hydrolysis nor is it accompanied by entrapment within S-K rings, which is a slower process requiring Scc3. Cryo-EM reveals that DNAs transported into E-S/E-K compartments are ‘clamped’ in a sub-compartment created by Scc2’s association with engaged heads whose coiled coils are folded around their elbow. We suggest that clamping may be a recurrent feature of cohesin complexes active in loop extrusion and that this conformation precedes the S-K entrapment required for sister chromatid cohesion.

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Cohesin Associates with Spindle Poles in a Mitosis-specific Manner and Functions in Spindle Assembly in Vertebrate Cells

Molecular Biology of the Cell ◽

10.1091/mbc.e08-04-0419 ◽

2009 ◽

Vol 20 (5) ◽

pp. 1289-1301 ◽

Cited By ~ 28

Author(s):

Xiangduo Kong ◽

Alexander R. Ball ◽

Eiichiro Sonoda ◽

Jie Feng ◽

Shunichi Takeda ◽

...

Keyword(s):

Chromosome Pairing ◽

Sister Chromatid ◽

Spindle Assembly ◽

Sister Chromatid Cohesion ◽

S Phase ◽

Mitotic Apparatus ◽

Spindle Poles ◽

Chromatid Cohesion ◽

Specific Manner

Cohesin is an essential protein complex required for sister chromatid cohesion. Cohesin associates with chromosomes and establishes sister chromatid cohesion during interphase. During metaphase, a small amount of cohesin remains at the chromosome-pairing domain, mainly at the centromeres, whereas the majority of cohesin resides in the cytoplasm, where its functions remain unclear. We describe the mitosis-specific recruitment of cohesin to the spindle poles through its association with centrosomes and interaction with nuclear mitotic apparatus protein (NuMA). Overexpression of NuMA enhances cohesin accumulation at spindle poles. Although transient cohesin depletion does not lead to visible impairment of normal spindle formation, recovery from nocodazole-induced spindle disruption was significantly impaired. Importantly, selective blocking of cohesin localization to centromeres, which disrupts centromeric sister chromatid cohesion, had no effect on this spindle reassembly process, clearly separating the roles of cohesin at kinetochores and spindle poles. In vitro, chromosome-independent spindle assembly using mitotic extracts was compromised by cohesin depletion, and it was rescued by addition of cohesin that was isolated from mitotic, but not S phase, cells. The combined results identify a novel spindle-associated role for human cohesin during mitosis, in addition to its function at the centromere/kinetochore regions.

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Identification and Characterization of Sa/Scc3p Subunits in the Xenopus and Human Cohesin Complexes

The Journal of Cell Biology ◽

10.1083/jcb.150.3.405 ◽

2000 ◽

Vol 150 (3) ◽

pp. 405-416 ◽

Cited By ~ 202

Author(s):

Ana Losada ◽

Tomoki Yokochi ◽

Ryuji Kobayashi ◽

Tatsuya Hirano

Keyword(s):

Sister Chromatid ◽

Somatic Tissue ◽

Sister Chromatid Cohesion ◽

Dominant Form ◽

Culture Cells ◽

Chromatid Cohesion ◽

Egg Extracts ◽

Xenopus Egg ◽

Xenopus Egg Extracts

A multisubunit protein complex, termed cohesin, plays an essential role in sister chromatid cohesion in yeast and in Xenopus laevis cell-free extracts. We report here that two distinct cohesin complexes exist in Xenopus egg extracts. A 14S complex (x-cohesinSA1) contains XSMC1, XSMC3, XRAD21, and a newly identified subunit, XSA1. In a second 12.5S complex (x-cohesinSA2), XSMC1, XSMC3, and XRAD21 associate with a different subunit, XSA2. Both XSA1 and XSA2 belong to the SA family of mammalian proteins and exhibit similarity to Scc3p, a recently identified component of yeast cohesin. In Xenopus egg extracts, x-cohesinSA1 is predominant, whereas x-cohesinSA2 constitutes only a very minor population. Human cells have a similar pair of cohesin complexes, but the SA2-type is the dominant form in somatic tissue culture cells. Immunolocalization experiments suggest that chromatin association of cohesinSA1 and cohesinSA2 may be differentially regulated. Dissociation of x-cohesinSA1 from chromatin correlates with phosphorylation of XSA1 in the cell-free extracts. Purified cdc2-cyclin B can phosphorylate XSA1 in vitro and reduce the ability of x-cohesinSA1 to bind to DNA or chromatin. These results shed light on the mechanism by which sister chromatid cohesion is partially dissolved in early mitosis, far before the onset of anaphase, in vertebrate cells.

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