Review
Cell Biology
Yukiko Imai, Ivan Olaya, Noriyoshi Sakai, Sean M. Burgess
Summary: Recent studies in zebrafish have provided insights on key features of meiotic chromosome dynamics, such as telomere clustering and homolog alignment. This review discusses the temporal progression of these events and the roles of proteins associated with homologous recombination.
FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY
(2021)
Review
Cell Biology
Elena Llano, Alberto M. Pendas
Summary: The synaptonemal complex (SC) forms during meiosis I and is involved in the synapses of homologous chromosomes, repair of double-strand breaks (DSBs), and formation of crossovers (COs). Defects in SC assembly or meiotic recombination machinery can cause meiotic arrest and infertility. Many proteins involved in these processes are meiosis-specific, but some also have roles in somatic DNA repair and are associated with cancer development.
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
Biochemistry & Molecular Biology
Hideo Tsubouchi
Summary: Homologous recombination (HR) is crucial for meiosis and is induced during meiotic prophase. The Hop2-Mnd1 complex, originally identified in budding yeast, is conserved across species and plays an essential role in meiosis. Accumulating evidence suggests that Hop2-Mnd1 promotes RecA-like recombinases for homology search and strand exchange. This review summarizes studies on the mechanism of the Hop2-Mnd1 complex in promoting HR and beyond.
Article
Multidisciplinary Sciences
Martin G. France, Janina Enderle, Sarah Roehrig, Holger Puchta, F. Chris H. Franklin, James D. Higgins
Summary: The study on the function of the synaptonemal complex in Arabidopsis indicates that it limits the formation of Class I crossover interference and disrupts the progressive alignment of chromosome axes in plants.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Review
Genetics & Heredity
Sarah N. Ur, Kevin D. Corbett
Summary: Meiotic cell division is a specialized process preparing for sexual reproduction, involving homologous chromosomes identifying each other and forming physical links through DNA recombination. The SMC family cohesin complexes and meiotic chromosome axis play crucial roles in organizing chromosomes and promoting recombination. The synaptonemal complex (SC) ensures high fidelity in meiotic recombination by assembling between homologs and providing feedback.
ANNUAL REVIEW OF GENETICS, VOL 55
(2021)
Article
Oncology
Rosario Ortiz, Silvia Juarez Chavero, Olga M. Echeverria, Abrahan Hernandez-Hernandez
Summary: The study utilized an ultrastructural DNA staining technique on mouse testis to observe the organization of DNA in the SC. Bubble-like staining patterns were observed in certain regions, indicating that the specific organization of DNA is determined by chromosome synapsis, regardless of homology or partial SC formation.
EXPERIMENTAL CELL RESEARCH
(2021)
Article
Cell Biology
Yukiko Imai, Kenji Saito, Kazumasa Takemoto, Fabien Velilla, Toshihiro Kawasaki, Kei-ichiro Ishiguro, Noriyoshi Sakai
Summary: The mutation in the zebrafish gene encoding the transverse filament protein Sycp1 leads to incomplete pairing of homologs in zebrafish meiosis, while not affecting double-strand break formation near telomeres.
FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY
(2021)
Article
Multidisciplinary Sciences
Laia Capilla-Perez, Stephanie Durand, Aurelie Hurel, Qichao Lian, Aurelie Chambon, Christelle Taochy, Victor Solier, Mathilde Grelon, Raphael Mercier
Summary: The spatial organization of transverse filaments is essential for CO formation during meiosis, with the absence of ZYP1 leading to an unexpected increase in CO formation. The tripartite synaptonemal complex plays a key role in regulating the number and distribution of COs, affecting CO interference and heterochiasmy.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Genetics & Heredity
Karen Voelkel-Meiman, Ashwini Oke, Arden Feil, Alexander Shames, Jennifer Fung, Amy J. MacQueen
Summary: The study reveals that while the SC proteins are not essential for recombination itself, they promote efficient mismatch repair at interhomolog recombination sites. Failure to repair mismatches leads to the formation of genotypically sectored colonies, with an increased frequency of unrepaired mismatches in cells lacking specific proteins.
Article
Genetics & Heredity
Jing Wang, Wen Wang, Jihong Li, Yirui Zhang, Kaikun Luo, Linmei Han, Caixia Xiang, Mingli Chai, Ziye Luo, Rurong Zhao, Shaojun Liu
Summary: Research shows that in the hybrid clone line of red crucian carp and common carp, there is a failure in chromosome pairing in the fertilized eggs, leading to sterility. However, after a long period of inhibition, the chromosome number doubles and successfully forms paired chromosomes and synaptonemal complex. This study further reveals the mechanisms of meiosis in hybrids.
FRONTIERS IN GENETICS
(2023)
Review
Cell Biology
Masaru Ito, Akira Shinohara
Summary: Meiocytes organize higher-order chromosome structures called synaptonemal complexes (SCs) and linear axes, which play crucial roles in the regulation of meiotic recombination. This review summarizes the importance of chromosome architecture in meiotic recombination, focusing on cohesin-mediated axis formation, tethered loop-axis complexes for DSB regulation, axial proteins for inter-homolog template bias, and crossover regulation in the context of SCs. The involvement of the SUMO and the ubiquitin-proteasome system in chromosome structure organization and meiotic recombination regulation is also discussed.
FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY
(2023)
Review
Developmental Biology
Kei-Ichiro Ishiguro
Summary: Meiosis is a crucial process for germ cell development. The sexually dimorphic chromosome architecture leads to sexual differences in meiotic recombination and homolog synapsis.
SEXUAL DEVELOPMENT
(2023)
Article
Plant Sciences
Maria Cuacos, Christophe Lambing, Miguel Pachon-Penalba, Kim Osman, Susan J. Armstrong, Ian R. Henderson, Eugenio Sanchez-Moran, F. Christopher H. Franklin, Stefan Heckmann
Summary: In Brassica rapa, axis formation and remodelling are crucial for meiotic fidelity, including synapsis and crossover (CO) formation. Mutants of ASY1 and PCH2 show altered distribution of CO, with asy1 plants being sterile and pch2 plants being semi-sterile, making PCH2 a potential target for breeding programs.
JOURNAL OF EXPERIMENTAL BOTANY
(2021)
Article
Biology
Rachael E. Barton, Lucia F. Massari, Daniel Robertson, Adele L. Marston
Summary: Cohesin organizes the genome by forming intra-chromosomal loops and inter-sister chromatid linkages. In meiosis, Eco1 acetyltransferase-dependent positioning of both chromatin loops and sister chromatid cohesion organizes meiotic chromosomes into functional domains.
Editorial Material
Cell Biology
Tomoyuki Fukuda, Tomotake Kanki
Summary: Mitophagy is a selective form of autophagy that degrades damaged or unnecessary mitochondria through double-membranous structures called phagophores. Atg43 has been identified as a mitophagy receptor in the fission yeast Schizosaccharomyces pombe, playing a role in stabilizing phagophore expansion on mitochondria by interacting with Atg8. This suggests that Atg43 may have acquired its mitophagic function through convergent evolution, as it shares no sequence similarity with mitophagy receptors in other organisms.
Article
Oncology
Rosario Ortiz, Silvia Juarez Chavero, Olga M. Echeverria, Abrahan Hernandez-Hernandez
Summary: The study utilized an ultrastructural DNA staining technique on mouse testis to observe the organization of DNA in the SC. Bubble-like staining patterns were observed in certain regions, indicating that the specific organization of DNA is determined by chromosome synapsis, regardless of homology or partial SC formation.
EXPERIMENTAL CELL RESEARCH
(2021)
Article
Biology
Tomoyuki Fukuda, Fajar Sofyantoro, Yen Teng Tai, Kim Hou Chia, Takato Matsuda, Takaaki Murase, Yuichi Morozumi, Hisashi Tatebe, Tomotake Kanki, Kazuhiro Shiozaki
Summary: The GATOR2 subunit Sea3 unexpectedly attenuates TORC1 activity by being physically and functionally proximal to GATOR1 in fission yeast. The GATOR complex in fission yeast is dispensable for TORC1 regulation in response to amino acid starvation, as cells instead activate the Gcn2 pathway to inhibit TORC1 and induce autophagy.
Article
Cell Biology
Shun-Ichi Yamashita, Masanao Kyuuma, Keiichi Inoue, Yuki Hata, Ryu Kawada, Masaki Yamabi, Yasuyuki Fujii, Junko Sakagami, Tomoyuki Fukuda, Kentaro Furukawa, Satoshi Tsukamoto, Tomotake Kanki
Summary: The study found that muscle disuse enhances mitophagy activity and the production of reactive oxygen species in atrophic skeletal muscles, suggesting a potential therapeutic target for disuse-induced muscle atrophy.
JOURNAL OF CELLULAR PHYSIOLOGY
(2021)
Editorial Material
Cell Biology
Tomoyuki Fukuda, Kazuhiro Shiozaki
Summary: The GATOR2 component Sea3 in fission yeast unexpectedly acts as part of GATOR1 to suppress TORC1. In fission yeast, GATOR1 is not required for amino acid starvation-induced TORC1 attenuation, which is mediated by the Gcn2 pathway. Absence of a nitrogen source suppresses TORC1 through GATOR1 and the Tsc1-Tsc2 complex.
Article
Biochemistry & Molecular Biology
Tatsuro Maruyama, Jahangir Md. Alam, Tomoyuki Fukuda, Shun Kageyama, Hiromi Kirisako, Yuki Ishii, Ichio Shimada, Yoshinori Ohsumi, Masaaki Komatsu, Tomotake Kanki, Hitoshi Nakatogawa, Nobuo N. Noda
Summary: Lipidation of Atg8 is crucial for autophagosome biogenesis, with two aromatic membrane-facing residues playing important roles in membrane morphology and autophagy regulation. These findings have implications for understanding the mechanisms underlying efficient autophagy in yeast and mammalian cells.
NATURE STRUCTURAL & MOLECULAR BIOLOGY
(2021)
Article
Biochemistry & Molecular Biology
Rosario Ortiz, Olga M. Echeverria, Sergej Masich, Christer Hoog, Abrahan Hernandez-Hernandez
Summary: This study analyzed the structure of the synaptonemal complex (SC) using cryo-fixation and electron microscopy. Compared to chemical fixation, cryo-fixation showed differences in the width of the central region of the SC and the density of the transverse filaments.
CHROMOSOME RESEARCH
(2022)
Article
Cell Biology
Anna Kouznetsova, Jian Guo Liu, Sonata Valentiniene, Hjalmar Brismar, Christer Hoog
Summary: Aging significantly impacts the chromosome segregation process in human oocytes, leading to aneuploidy, infertility, and developmental disorders. As age increases, the likelihood of chromosome segregation irregularities also increases, resulting in a higher incidence of aneuploidy.
Article
Biochemistry & Molecular Biology
Abrahan Hernandez-Hernandez, Tayde Lopez-Santaella, Aranxa Torres-Caballero, Amarantha Serrato, Ulises Torres-Flores, Diego Montesinos-Valencia, Fernando Chico-Ponce De Leon, Vicente Gonzalez-Carranza, Samuel Torres-Garcia, Rosa Rebollar-Vega, Inti Alberto De la Rosa-Velazquez, Rosario Ortiz, Monserrat Perez-Ramirez, Normand Garcia-Hernandez, Antonio Garcia-Mendez, Francisco Arenas-Huertero
Summary: Central nervous system tumors are common in childhood and contribute to cancer-related mortality. This study explored the transcriptomic landscape of pediatric astrocytoma, focusing on the genetic alterations associated with tumorigenesis. The findings provide insights into the biological functions and pathways involved in astrocytoma, and establish a transcriptional signature for identifying different grades of the tumor.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Cell Biology
Tomoyuki Fukuda, Tetsu Saigusa, Kentaro Furukawa, Keiichi Inoue, Shun-ichi Yamashita, Tomotake Kanki
Summary: The endoplasmic reticulum (ER) undergoes selective autophagy called reticulophagy or ER-phagy. Reticulon- and receptor expression enhancing protein (REEP)-like ER-shaping proteins, such as budding yeast Atg40, act as reticulophagy receptors to stabilize the phagophore on the ER by interacting with phagophore-conjugated Atg8. Hva22, a REEP family protein in fission yeast, promotes reticulophagy without Atg8-binding capacity and its role can be replaced by expressing Atg40 independently of its Atg8-binding ability.
Article
Biochemistry & Molecular Biology
Tomoyuki Fukuda, Kentaro Furukawa, Tatsuro Maruyama, Shun-ichi Yamashita, Daisuke Noshiro, Chihong Song, Yuta Ogasawara, Kentaro Okuyama, Jahangir Md Alam, Manabu Hayatsu, Tetsu Saigusa, Keiichi Inoue, Kazuho Ikeda, Akira Takai, Lin Chen, Vikramjit Lahiri, Yasushi Okada, Shinsuke Shibata, Kazuyoshi Murata, Daniel J. Klionsky, Nobuo N. Noda, Tomotake Kanki
Summary: Mitophagy is important for maintaining mitochondrial homeostasis by selectively degrading mitochondria. In this study, a new mitochondrial fission factor called Atg44, also referred to as mitofissin, was identified in yeast as essential for mitophagy. Mitofissin deficiency resulted in recognition of mitochondria as cargo by the mitophagy machinery, but a lack of mitochondrial fission prevented engulfment by the autophagosome precursor. It was shown that mitofissin directly binds to lipid membranes and promotes membrane fission, suggesting that it plays a direct role in driving mitochondrial fission required for mitophagy.
Editorial Material
Biochemistry & Molecular Biology
Tomoyuki Fukuda, Kentaro Furukawa, Tomotake Kanki
Summary: This article discusses the paper "The mitochondrial intermembrane space protein mitofissin drives mitochondrial fission required for mitophagy" (this issue of Molecular Cell) and interviews the corresponding author Tomotake Kanki and co-first authors Tomoyuki Fukuda and Kentaro Furu-kawa about their career paths, interests outside of their fields, and how they balance work and life.
Article
Cell Biology
Nanaho Fukuda, Tomoyuki Fukuda, Piergiorgio Percipalle, Kanako Oda, Nobuyuki Takei, Kevin Czaplinski, Kazushige Touhara, Yoshihiro Yoshihara, Toshikuni Sasaoka
Summary: It is found that hnRNP A/B is highly expressed in developing olfactory sensory neurons (OSNs), and its knockout leads to reduction in mature OSNs and aberrant axon targeting. hnRNP A/B is shown to bind to a group of mRNAs related to axon projections and synapse assembly. Deletion of the hnRNP A/B-recognition motif in the 3' UTR of Pcdha impairs its expression at the OSN axon terminals.
Editorial Material
Cell Biology
Tomoyuki Fukuda, Kentaro Furukawa, Tatsuro Maruyama, Nobuo N. Noda, Tomotake Kanki
Summary: Mitophagy is a selective form of autophagy that targets dysfunctional or superfluous mitochondria for degradation. Our recent study has identified Atg44 as a mitochondrial fission factor that generates mitochondrial fragments suitable for phagophore engulfment. We propose the term mitofissin to refer to Atg44 and its homologous proteins that might participate in diverse cellular processes.
Article
Biochemistry & Molecular Biology
Yen Teng Tai, Tomoyuki Fukuda, Yuichi Morozumi, Hayato Hirai, Arisa H. Oda, Yoshiaki Kamada, Yutaka Akikusa, Tomotake Kanki, Kunihiro Ohta, Kazuhiro Shiozaki
Summary: TORC1 is activated in response to nutrient availability and growth factors, promoting cellular anabolism and proliferation. This study revealed that TORC1 phosphorylates and protects the transcription factor Sfp1, which then positively regulates ribosome production genes together with Ifh1 and Fhl1. The transcriptional regulation of ribosome biosynthesis genes by Sfp1, Ifh1, and Fhl1 is one of the key pathways through which nutrient-activated TORC1 promotes cell proliferation.
MOLECULAR AND CELLULAR BIOLOGY
(2023)