Article
Cell Biology
Shun Kato, Kohei Arasaki, Natsuki Tokutomi, Yuzuru Imai, Tsuyoshi Inoshita, Nobutaka Hattori, Taeko Sasaki, Miyuki Sato, Yuichi Wakana, Hiroki Inoue, Mitsuo Tagaya
Summary: This study compared the localization and function of fly and nematode Stx17 with that of human Stx17 in HeLa cells. Fly Stx17 predominantly mediates autophagy in the cytosol, while nematode Stx17 facilitates mitochondrial division in mitochondria. Differences in function are likely due to structural differences in the C-terminal tail.
JOURNAL OF CELL SCIENCE
(2021)
Review
Biology
Manuel F. Varela, Anely Ortiz-Alegria, Manjusha Lekshmi, Jerusha Stephen, Sanath Kumar
Summary: A phospholipid membrane acts as a barrier for the passage of molecules across living cells, but this barrier can be circumvented by transporter proteins. The major facilitator superfamily includes transporters found in all living organisms and plays important roles in various biological processes. The antiporter motif, known as motif C, is involved in the molecular mechanism of antimicrobial efflux.
Review
Genetics & Heredity
Changfu Liu, Weihao Zhang, Wenge Xing
Summary: Gene transcription is a complex biological process involving various factors, enzymes, and nucleotides. Ssu72, a CTD phosphatase, plays a crucial role in transcription by regulating RNAPII activity and affecting the conformational changes of CTD. Its functions also extend to balancing phosphate homeostasis and controlling chromosome behaviors, highlighting its importance beyond gene transcription.
Article
Geriatrics & Gerontology
Susan Law, Ilja Ormel, Stephanie Babinski, Kerry Kuluski, Amelie Quesnel-Vallee
Summary: Caregivers play important roles in healthcare provision, but they face significant health and economic costs. Through qualitative interviews, this study identified caregivers' roles as resources, colleagues, and clients, as well as highlighted the additional role of care coordinator. Understanding these roles and challenges can lead to better policies and support for caregivers.
Article
Biochemistry & Molecular Biology
Reito Watanabe, Yasuhiro Hirano, Masatoshi Hara, Yasushi Hiraoka, Tatsuo Fukagawa
Summary: The kinetochore, essential for chromosome segregation during mitosis, is assembled through dynamic processes involving numerous kinetochore proteins. The study used fluorescence recovery after photobleaching (FRAP) analysis to reveal the dynamics of kinetochore assembly. Results showed that CENP-C is mobile during interphase but immobile during mitosis, while CENP-T and CENP-H are immobile during both interphase and mitosis. The mobility of Dsn1, a component of the Mis12 complex, depended on CENP-C mobility during mitosis.
CHROMOSOME RESEARCH
(2022)
Review
Genetics & Heredity
Takeshi Sakuno, Yasushi Hiraoka
Summary: The key difference between meiosis and mitosis is that during meiosis, pairing and segregation of homologous chromosomes occur, and there are significant changes in the morphology of sister chromatids. The meiosis-specific cohesin complex, especially the Rec8 subunit, plays a crucial role in regulating the pairing and recombination of homologous chromosomes in meiosis.
Review
Cell Biology
Yanjing Li, Kexue Ge, Tingting Li, Run Cai, Yong Chen
Summary: This review highlights the recent progress in structural studies of histone lysine methyltransferases (HKMTs), which play important roles in regulating chromatin structure and gene expression. The focus is on representative HKMTs (H3K4, H3K27, H3K36, H3K79, and H4K20 methyltransferases) in complex with nucleosomes, with emphasis on understanding the molecular mechanisms of nucleosome recognition and trans-histone crosstalk by these enzymes. These structural studies shed light on the roles of HKMTs in tumorigenesis and provide a basis for developing novel therapeutic approaches targeting HKMTs in cancer.
Article
Multidisciplinary Sciences
Lijie Zhao, Naizhe Huang, Jun Mencius, Yanjing Li, Ying Xu, Yongxin Zheng, Wei He, Na Li, Jun Zheng, Min Zhuang, Shu Quan, Yong Chen
Summary: In this study, two key mechanisms of DPY30 in regulating MLL1 activity were revealed: a nucleosome-independent mechanism and a nucleosome-specific mechanism. DPY30 stabilizes ASH2L to increase the stability and interactions of the MLL1 complex, promoting its compaction and stabilization and enhancing its activity on substrates. Additionally, DPY30-stabilized ASH2L acquires additional interfaces with H3 and nucleosomal DNA, boosting the methyltransferase activity of the MLL1 complex on nucleosomes.
Article
Cell Biology
Megumi Tsuchiya, Weixia Kong, Yasushi Hiraoka, Tokuko Haraguchi, Hidesato Ogawa
Summary: DNA transfection efficiency can be improved by inhibiting the phosphorylation process of p62 by TBK1, which reduces the intracellular degradation of transfected DNA.
Article
Biochemistry & Molecular Biology
Yanjing Li, Lijie Zhao, Yuebin Zhang, Ping Wu, Ying Xu, Jun Mencius, Yongxin Zheng, Xiaoman Wang, Wancheng Xu, Naizhe Huang, Xianwen Ye, Ming Lei, Pan Shi, Changlin Tian, Chao Peng, Guohui Li, Zhijun Liu, Shu Quan, Yong Chen
Summary: This study develops methodologies to measure the methylation rate difference between different states of methylation and demonstrates that MLL proteins possess distinct product specificities. Structural analyses reveal that the dynamics of conserved tyrosine residues fine-tune the product specificity, and the variation in intramolecular interaction affects the dynamics, determining the product specificities of MLL proteins.
Article
Cell Biology
Hui-Ju Yang, Haruhiko Asakawa, Fu-An Li, Tokuko Haraguchi, Hsiu-Ming Shih, Yasushi Hiraoka
Summary: The nuclear pore complex (NPC) acts as a permeable barrier between the nucleus and cytoplasm. Deficiency in nucleoporin Nup132 led to transient leakage of nuclear proteins during meiosis I in the fission yeast Schizosaccharomyces pombe. The leakage was accompanied by the release of SUMO-specific protease Ulp1 from the NPC. Retention of Ulp1 at the nuclear pore prevented protein leakage and restored normal meiosis.
Article
Multidisciplinary Sciences
Domagoj Vugic, Isaac Dumoulin, Charlotte Martin, Anna Minello, Lucia Alvaro-Aranda, Jesus Gomez-Escudero, Rady Chaaban, Rana Lebdy, Catharina von Nicolai, Virginie Boucherit, Cyril Ribeyre, Angelos Constantinou, Aura Carreira
Summary: The authors demonstrate that the dsDNA binding function at the N-terminus of BRCA2 prevents nucleotide depletion-induced ssDNA gaps but not those induced by PARP inhibition. Replication stress is a major source of genomic instability and is intrinsic to cancer cells. BRCA2 deficiency results in replication stress and the protein's N-terminal DNA binding domain plays a crucial role in preventing and repairing ssDNA gaps caused by nucleotide depletion.
NATURE COMMUNICATIONS
(2023)
Article
Biology
Rana Lebdy, Julie Patouillard, Marion Larroque, Serge Urbach, Raghida Abou Merhi, Christian Larroque, Cyril Ribeyre
Summary: RIF1 protein localizes near centromeres and suppresses replication-associated genomic instability.
LIFE SCIENCE ALLIANCE
(2023)
Article
Cell Biology
Yasuhiro Hirano, Yusuke Ohno, Yoshino Kubota, Tatsuo Fukagawa, Akio Kihara, Tokuko Haraguchi, Yasushi Hiraoka
Summary: Recent studies have revealed that enzymes catalyzing lipid synthesis play a role in maintaining the integrity of the nuclear envelope (NE), but the mechanism involved remains unclear. In this study, the ceramide synthase homolog, Tlc4, was found to suppress NE defects in cells lacking the NE proteins Lem2 and Bqt4. Tlc4, which possesses a conserved TRAM/LAG1/CLN8 domain, functions through its non-catalytic activity and localizes at the NE, endoplasmic reticulum, and cisand medial-Golgi cisternae. The Golgi localization of Tlc4 is closely linked to its activity of suppressing NE defects in the double-deletion mutant of Lem2 and Bqt4.
JOURNAL OF CELL SCIENCE
(2023)
Article
Multidisciplinary Sciences
Rekha Rai, Kevin Biju, Wenqi Sun, Tori Sodeinde, Amer Al-Hiysat, Jaida Morgan, Xianwen Ye, Xueqing Li, Yong Chen, Sandy Chang
Summary: This study reveals that the basic domain of TRF2 (TRF2(B)) and RAP1 cooperate to repress homology directed repair (HDR) at telomeres and prevent the formation of ultrabright telomere structures.
NATURE COMMUNICATIONS
(2023)
Letter
Cell Biology
Naijin Zhang, Ying Zhang, Yong Chen, Hao Qian, Boquan Wu, Saien Lu, Shilong You, Wancheng Xu, Yuanming Zou, Xinyue Huang, Wenbin Wang, Jingwei Liu, Da Li, Liu Cao, Yingxian Sun
Article
Biochemistry & Molecular Biology
Minh Chau Nguyen, Duo Wang, Brianna J. Klein, Yong Chen, Tatiana G. Kutateladze
Summary: We investigate the association of Taf14 with other subunits of essential complexes and describe the mechanisms and factors that affect this association. Our findings provide insights into how Taf14 is distributed among the complexes.
BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS
(2023)
Article
Cell Biology
Min Chen, Kangjunjie Wang, Ying Han, Shukun Yan, Huairui Yuan, Qiuli Liu, Long Li, Ni Li, Hongwen Zhu, Dayun Lu, Kaihua Wang, Fen Liu, Dakui Luo, Yuxue Zhang, Jun Jiang, Dali Li, Lei Zhang, Hongbin Ji, Hu Zhou, Yong Chen, Jun Qin, Daming Gao
Summary: AKT kinase plays a crucial role in cell metabolism and survival, and its activation is strictly regulated. We have identified XAF1 as a direct interacting protein of AKT1, which binds to the N-terminal region of AKT1 to block its activation. XAF1 knockout leads to AKT activation in mouse muscle and fat tissues and reduces body weight gain and insulin resistance induced by high-fat diet.
Article
Biochemistry & Molecular Biology
Rana Lebdy, Marine Canut, Julie Patouillard, Jean-Charles Cadoret, Anne Letessier, Josiane Ammar, Jihane Basbous, Serge Urbach, Benoit Miotto, Angelos Constantinou, Raghida Abou Merhi, Cyril Ribeyre
Summary: This study identifies a protein called GNL3 that protects DNA integrity during replication by limiting DNA resection. It interacts with the DNA replication initiation factor ORC2 in the nucleolus to control the number of activated replication origins and prevent DNA resection.