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Qi Yi, Qinfu Chen, Cai Liang, Haiyan Yan, Zhenlei Zhang, Xingfeng Xiang, Miao Zhang, Feifei Qi, Linli Zhou, Fangwei Wang
Heterochromatin protein-1 (HP1) is a key component of heterochromatin. Reminiscent of the cohesin complex which mediates sister-chromatid cohesion, most HP1 proteins in mammalian cells are displaced from chromosome arms during mitotic entry, whereas a pool remains at the heterochromatic centromere region. The function of HP1 at mitotic centromeres remains largely elusive. Here, we show that double knockout (DKO) of HP1α and HP1γ causes defective mitosis progression and weakened centromeric cohesion. While mutating the chromoshadow domain (CSD) prevents HP1α from protecting sister-chromatid cohesion, centromeric targeting of HP1α CSD alone is sufficient to rescue the cohesion defects in HP1 DKO cells...
February 28, 2018: EMBO Reports
Nuria Ferrandiz, Consuelo Barroso, Oana Telecan, Nan Shao, Hyun-Min Kim, Sarah Testori, Peter Faull, Pedro Cutillas, Ambrosious P Snijders, Monica P Colaiácovo, Enrique Martinez-Perez
The formation of haploid gametes from diploid germ cells requires the regulated two-step release of sister chromatid cohesion (SCC) during the meiotic divisions. Here, we show that phosphorylation of cohesin subunit REC-8 by Aurora B promotes SCC release at anaphase I onset in C. elegans oocytes. Aurora B loading to chromatin displaying Haspin-mediated H3 T3 phosphorylation induces spatially restricted REC-8 phosphorylation, preventing full SCC release during anaphase I. H3 T3 phosphorylation is locally antagonized by protein phosphatase 1, which is recruited to chromosomes by HTP-1/2 and LAB-1...
February 26, 2018: Nature Communications
Jan G Ruppert, Kumiko Samejima, Melpomeni Platani, Oscar Molina, Hiroshi Kimura, A Arockia Jeyaprakash, Shinya Ohta, William C Earnshaw
The chromosomal passenger complex (CPC) is directed to centromeres during mitosis via binding to H3T3ph and Sgo1. Whether and how heterochromatin protein 1α (HP1α) influences CPC localisation and function during mitotic entry is less clear. Here, we alter HP1α dynamics by fusing it to a CENP-B DNA-binding domain. Tethered HP1 strongly recruits the CPC, destabilising kinetochore-microtubule interactions and activating the spindle assembly checkpoint. During mitotic exit, the tethered HP1 traps active CPC at centromeres...
February 21, 2018: EMBO Journal
David S Moura, Ignacio Campillo-Marcos, Marta Vázquez-Cedeira, Pedro A Lazo
Regulation of cell division requires the integration of signals implicated in chromatin reorganization and coordination of its sequential changes in mitosis. Vaccinia-related kinase 1 (VRK1) and Aurora B (AURKB) are two nuclear kinases involved in different steps of cell division. We have studied whether there is any functional connection between these two nuclear kinases, which phosphorylate histone H3 in Thr3 and Ser10, respectively. VRK1 and AURKB are able to form a stable protein complex, which represents only a minor subpopulation of each kinase within the cell and is detected following nocodazole release...
January 16, 2018: Cellular and Molecular Life Sciences: CMLS
Cai Liang, Qinfu Chen, Qi Yi, Miao Zhang, Haiyan Yan, Bo Zhang, Linli Zhou, Zhenlei Zhang, Feifei Qi, Sheng Ye, Fangwei Wang
Sister-chromatid cohesion mediated by the cohesin complex is fundamental for precise chromosome segregation in mitosis. Through binding the cohesin subunit Pds5, Wapl releases the bulk of cohesin from chromosome arms in prophase, whereas centromeric cohesin is protected from Wapl until anaphase onset. Strong centromere cohesion requires centromeric localization of the mitotic histone kinase Haspin, which is dependent on the interaction of its non-catalytic N-terminus with Pds5B. It remains unclear how Haspin fully blocks the Wapl-Pds5B interaction at centromeres...
November 14, 2017: EMBO Reports
Jong-Eun Kim, Sung-Young Lee, Mi Jang, Hyo-Kyung Choi, Jong Hun Kim, Hanyong Chen, Tae-Gyu Lim, Zigang Dong, Ki Won Lee
Targeting epigenetic changes in gene expression in cancer cells may offer new strategies for the development of selective cancer therapies. In the present study, we investigated coumestrol, a natural compound exhibiting broad anti-cancer effects against skin melanoma, lung cancer and colon cancer cell growth. Haspin kinase was identified as a direct target protein of coumestrol using kinase profiling analysis. Histone H3 is a direct substrate of haspin kinase. We observed haspin kinase overexpression as well as greater phosphorylation of histone H3 at threonine 3 (Thr-3) in the cancer cells compared to normal cells...
October 24, 2017: International Journal of Molecular Sciences
Yang Liu, Handong Su, Yalin Liu, Jing Zhang, Qianhua Dong, James A Birchler, Fangpu Han
Haspin-mediated phosphorylation of histone H3 at threonine 3 (H3T3ph) promotes proper deposition of Aurora B at the inner centromere to ensure faithful chromosome segregation in metazoans. However, the function of H3T3ph remains relatively unexplored in plants. Here, we show that in maize (Zea mays L.) mitotic cells, H3T3ph is concentrated at pericentromeric and centromeric regions. Additional weak H3T3ph signals occur between cohered sister chromatids at prometaphase. Immunostaining on dicentric chromosomes reveals that an inactive centromere cannot maintain H3T3ph at metaphase, indicating that a functional centromere is required for H3T3 phosphorylation...
December 2017: Plant Journal: for Cell and Molecular Biology
Nathalie Gisèle Amoussou, André Bigot, Christos Roussakis, Jean-Michel H Robert
Protein kinases constitute a large group of enzymes in eukaryotes and have an important role in many cellular processes. Several of these proteins are active kinases, such as haploid germ cell-specific nuclear protein kinase (Haspin), an atypical eukaryotic protein kinase that lacks sequence similarity with other eukaryotic protein kinases. Haspin is a serine/threonine kinase that associates with chromosome and phosphorylates threonine 3 of histone 3 during mitosis. Haspin overexpression or deletion results in defective mitosis...
October 13, 2017: Drug Discovery Today
Lili Han, Peiling Wang, Yang Sun, Sijing Liu, Jun Dai
Background: Melanoma is a heterogeneous malignancy that presents an immense challenge in therapeutic development. Recent approaches targeting the oncogenic MAP kinase pathways have shown tremendous improvement in the overall survival of patients with advanced melanoma. However, there is still an urgent need for identification of new strategies to overcome drug resistances and to improve therapeutic efficacy. Haspin (Haploid Germ Cell-Specific Nuclear Protein Kinase) belongs to a selected group of mitotic kinases and is required for normal mitosis progression...
2017: Journal of Cancer
Simon I R Lane, Stephanie L Morgan, Tianyu Wu, Josie K Collins, Julie A Merriman, Elias ElInati, James M Turner, Keith T Jones
Mouse oocytes carrying DNA damage arrest in meiosis I, thereby preventing creation of embryos with deleterious mutations. The arrest is dependent on activation of the spindle assembly checkpoint, which results in anaphase-promoting complex (APC) inhibition. However, little is understood about how this checkpoint is engaged following DNA damage. Here, we find that within minutes of DNA damage checkpoint proteins are assembled at the kinetochore, not at damage sites along chromosome arms, such that the APC is fully inhibited within 30 min...
October 1, 2017: Development
Masashi Hada, Jihye Kim, Erina Inoue, Yuko Fukuda, Hiromitsu Tanaka, Yoshinori Watanabe, Yuki Okada
Histone phosphorylation is sometimes associated with mitosis and meiosis. We have recently identified a phosphorylation of the 127th threonine on TH2A (pTH2A), a germ cell-specific H2A variant, in condensed spermatids and mitotic early preimplantation embryos of mice. Here, we further report the existence of pTH2A at the centromeres in metaphase I spermatocytes and oocytes. Moreover, we identified Haspin, a known kinase for the 3rd threonine on H3, is responsible for pTH2A in vivo. In contrast to the severe meiotic defect in oocytes treated with a Haspin inhibitor, pTH2A-deficient mice, in which the 127th threonine was replaced by alanine, maintained the fertility and exhibited no obvious defect in both oocytes and spermatogenesis...
December 2017: Chromosoma
Suzanne M Quartuccio, Shweta S Dipali, Karen Schindler
Aneuploidy is the leading genetic abnormality contributing to infertility, and chromosome segregation errors are common during female mammalian meiosis I (MI). Previous results indicate that haspin kinase regulates resumption of meiosis from prophase arrest, chromosome condensation, and kinetochore-microtubule attachments during early prometaphase of MI. Here we report that haspin inhibition in late prometaphase I causes acceleration of MI, bypass of the spindle assembly checkpoint (SAC), and loss of interchromatid axis-localized Aurora kinase C...
August 15, 2017: Molecular Biology of the Cell
Sanne Hindriksen, Arne J Bramer, My Anh Truong, Martijn J M Vromans, Jasmin B Post, Ingrid Verlaan-Klink, Hugo J Snippert, Susanne M A Lens, Michael A Hadders
The CRISPR/Cas9 system is a highly effective tool for genome editing. Key to robust genome editing is the efficient delivery of the CRISPR/Cas9 machinery. Viral delivery systems are efficient vehicles for the transduction of foreign genes but commonly used viral vectors suffer from a limited capacity in the genetic information they can carry. Baculovirus however is capable of carrying large exogenous DNA fragments. Here we investigate the use of baculoviral vectors as a delivery vehicle for CRISPR/Cas9 based genome-editing tools...
2017: PloS One
G Combes, I Alharbi, L G Braga, S Elowe
Polo-like kinase 1 (PLK1), the prototypical member of the polo-like family of serine/threonine kinases, is a pivotal regulator of mitosis and cytokinesis in eukaryotes. Many layers of regulation have evolved to target PLK1 to different subcellular structures and to its various mitotic substrates in line with its numerous functions during mitosis. Collective work is starting to illuminate an important set of substrates for PLK1: the mitotic kinases that together ensure the fidelity of the cell division process...
August 24, 2017: Oncogene
Katrin Kestav, Asko Uri, Darja Lavogina
BACKGROUND: Haspin (haploid germ cell-specific nuclear protein kinase) is an atypical serine/threonine-protein kinase that was for a long time considered an inactive pseudokinase due to low degree of structural homology of Haspin with the 'classical' protein kinases. However, the discovery of Haspin-catalyzed phosphorylation of histone H3 at Thr3 residue unveiled importance of Haspin in mitosis and provided yet another link between mitotic phosphorylation pathways and chromatin modifications...
2017: Current Medicinal Chemistry
Yuhei Goto, Yuya Yamagishi, Miyuki Shintomi-Kawamura, Mayumi Abe, Yuji Tanno, Yoshinori Watanabe
Sister-chromatid cohesion is established by the cohesin complex in S phase and persists until metaphase, when sister chromatids are captured by microtubules emanating from opposite poles [1]. The Aurora-B-containing chromosome passenger complex (CPC) plays a crucial role in achieving chromosome bi-orientation by correcting erroneous microtubule attachment [2]. The centromeric localization of the CPC relies largely on histone H3-T3 phosphorylation (H3-pT3), which is mediated by the mitotic histone kinase Haspin/Hrk1 [3-5]...
April 3, 2017: Current Biology: CB
Linli Zhou, Cai Liang, Qinfu Chen, Zhenlei Zhang, Bo Zhang, Haiyan Yan, Feifei Qi, Miao Zhang, Qi Yi, Youchen Guan, Xingfeng Xiang, Xiaoqing Zhang, Sheng Ye, Fangwei Wang
Sister-chromatid cohesion, mediated by the multi-subunit cohesin complex, must be precisely regulated to prevent chromosome mis-segregation. In prophase and prometaphase, whereas the bulk of cohesin on chromosome arms is removed by its antagonist Wapl, cohesin at centromeres is retained to ensure chromosome biorientation until anaphase onset. It remains incompletely understood how centromeric cohesin is protected against Wapl in mitosis. Here we show that the mitotic histone kinase Haspin binds to the cohesin regulatory subunit Pds5B through a conserved YGA/R motif in its non-catalytic N terminus, which is similar to the recently reported YSR-motif-dependent binding of Wapl to Pds5B...
April 3, 2017: Current Biology: CB
Koji Ono, Hiroshi Banno, Masanori Okaniwa, Takaharu Hirayama, Naoki Iwamura, Yukiko Hikichi, Saomi Murai, Maki Hasegawa, Yuka Hasegawa, Kazuko Yonemori, Akito Hata, Kazunobu Aoyama, Douglas R Cary
To develop a novel series of CDK8/19 dual inhibitors, we employed structure-based drug design using docking models based on a library compound, 4,5-dihydroimidazolo[3',4':3,4]benzo[1,2-d]isothiazole 16 bound to CDK8. We designed various [5,6,5]-fused tricyclic scaffolds bearing a carboxamide group to maintain predicted interactions with the backbone CO and NH of Ala100 in the CDK8 kinase hinge region. We found that 4,5-dihydrothieno[3',4':3,4]benzo[1,2-d]isothiazole derivative 29a showed particularly potent enzymatic inhibitory activity in both CDK8/19 (CDK8 IC50 : 0...
April 15, 2017: Bioorganic & Medicinal Chemistry
Katrin Kestav, Kaido Viht, Anton Konovalov, Erki Enkvist, Asko Uri, Darja Lavogina
The atypical protein kinase haspin is a key player in mitosis by catalysing the phosphorylation of Thr3 in histone H3, and thus ensuring the normal function of the chromosomal passenger complex. Here, we report the development of bisubstrate-analogue inhibitors targeting haspin. The compounds were constructed by linking 5-iodotubercidin to the N terminus of histone H3 peptide. The new conjugates show high affinity (sub-nanomolar KD ) towards haspin as well as slow kinetics of association and dissociation (residence time of several hours)...
April 18, 2017: Chembiochem: a European Journal of Chemical Biology
Fazhi Yu, Ya Jiang, Lucy Lu, Mimi Cao, Yulong Qiao, Xing Liu, Dan Liu, Terry Van Dyke, Fangwei Wang, Xuebiao Yao, Jing Guo, Zhenye Yang
Aurora-A kinase functions mainly in centrosome maturation, separation and spindle formation. It has also been found to be amplified or overexpressed in a range of solid tumors, which is linked with tumor progression and poor prognosis. Importantly, Aurora-A inhibitors are being studied in a number of ongoing clinical trials. However, whether and how Aurora-A has a role in the regulation of the mitotic checkpoint is controversial. Additionally, the function of nuclear-accumulated Aurora-A in late G2 phase is not clear...
2017: Cell Discovery
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