Article
Cell Biology
Zachary McDargh, Tianyi Zhu, Hongkang Zhu, Ben O'Shaughnessy
Summary: This study used molecular simulations to investigate the role of cofilin in the contractile ring during cell division. The simulations revealed that the absence of cofilin led to an increase in ring tension, resulting in bridging instabilities. This research identified the critical role of cofilin in actomyosin turnover and its importance in protecting the contractile ring during cytokinesis.
JOURNAL OF CELL SCIENCE
(2023)
Article
Microbiology
Josiah J. Morrison, Colby N. Ferreira, Evelyn M. Siler, Katie Nelson, Catherine E. Trebino, Benjamin Piraino, Jodi L. Camberg
Summary: During cell division in Escherichia coli, the highly conserved tubulin homolog FtsZ assembles into a ring-like structure called the Z-ring at the septation site. FtsZ polymers interact with membrane-associated proteins, predominantly FtsA, for recruitment to the membrane surface. This study demonstrates the importance of specific amino acid residues in FtsA for its function in vitro and in vivo.
FRONTIERS IN MICROBIOLOGY
(2023)
Article
Multidisciplinary Sciences
Claudia Matthaeus, Kem A. Sochacki, Andrea M. Dickey, Dmytro Puchkov, Volker Haucke, Martin Lehmann, Justin W. Taraska
Summary: This study investigates the key proteins that regulate the curvature of caveolae using correlative super-resolution light and electron microscopy. The authors discover that caveolins, cavins, and EHD2 form a cohesive structural unit, regulated by intermittent associations with Pacsin2 and EHBP1, to control the curvature of caveolae.
NATURE COMMUNICATIONS
(2022)
Article
Cell Biology
Kimberly Bellingham-Johnstun, Zoe L. Tyree, Jessica Martinez-Baird, Annelise Thorn, Caroline Laplante
Summary: Actin-microtubule interactions are crucial for cell division, but their influence on the mechanical properties and functions of these polymers in live cells is still unknown. The assembly of microtubules in the post-anaphase array (PAA) of fission yeast relies on the recruitment of Mto1p by Myp2p. However, the organization of this microtubule array and its impact on the attachment to the contractile ring are unclear.
Article
Cell Biology
Takeru Arima, Keisuke Okita, Shigehiko Yumura
Summary: In this study, transmission electron microscopy was used to observe actin and myosin II filaments in the contractile rings of dividing Dictyostelium cells. The development of a novel method allowed for the synchronization of cytokinesis and high-frequency visualization of dividing cells undergoing cytokinesis. The length and alignment of individual filaments within the contractile rings were examined, revealing the gradual decrease in actin filament length and the perpendicular reorientation of actin and myosin II filaments during furrow constriction. Myosin II was found to regulate both the lengths and alignments of actin filaments, while dynamin-like protein A and cortexillins were involved in regulating filament length and alignment, respectively.
Article
Multidisciplinary Sciences
Sathish Thiyagarajan, Shuyuan Wang, Ting Gang Chew, Junqi Huang, Lokesh Kumar, Mohan K. Balasubramanian, Ben O'Shaughnessy
Summary: This study observed the full course of instability in isolated cytokinetic contractile rings, revealing that the turnover time of myosin II controls actomyosin contractile instability in normal cells.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Review
Immunology
Alexander A. Morano, Jeffrey D. Dvorin
Summary: The actomyosin contractile ring is a conserved feature in eukaryotic cytokinesis, but the structure and force generation mechanism of the basal complex in Apicomplexans, which lack myosin II homolog, remain poorly understood. By comparing with well-studied cytokinetic mechanisms in other organisms, new research directions and possible answers are suggested to explore the diversity and divergence of Apicomplexans.
FRONTIERS IN CELLULAR AND INFECTION MICROBIOLOGY
(2021)
Article
Cell Biology
Federica Arbizzani, Manos Mavrakis, Marta Hoya, Juan Carlos Ribas, Sophie Brasselet, Anne Paoletti, Sergio A. Rincon
Summary: In this study, the organization of septin filaments during cell division and its cell cycle regulation were investigated using fission yeast. The findings suggest that an anillin-like protein Mid2 plays a crucial role in promoting septin filament compaction and assembly, which is tightly controlled by the cell cycle.
Article
Biophysics
Daniel B. Cortes, Paul S. Maddox, Francois J. Nedelec, Amy Shaub Maddox
Summary: In this study, the researchers used a microfluidic device and high-numerical-aperture light-sheet microscopy to measure the dynamic changes in cytokinetic ring component abundance. They implemented the measured data into a model and observed biologically realistic cytokinetic kinetics. The findings emphasize the importance of network composition, particularly motor filament abundance, for actomyosin contraction kinetics.
BIOPHYSICAL JOURNAL
(2023)
Article
Physics, Fluids & Plasmas
Elisa Floris, Andrea Piras, Francesco Saverio Pezzicoli, Marco Zamparo, Luca Dall'Asta, Andrea Gamba
Summary: Molecular sorting is a crucial process in eukaryotic cells that allows for the concentration of specific chemical factors in different cell membrane subregions, giving them distinct chemical identities and functional properties. A recent phenomenological theory proposes that molecular sorting arises from phase separation-driven sorting domains and domain-induced membrane bending, resulting in the formation of lipid vesicles enriched in the sorted molecules. The efficiency of molecular distillation is found to be influenced by the critical size of phase separated domains. Experimental observations show that sorting domains can be classified into unproductive and productive domains, with the latter evolving into vesicles that detach from the membrane system. The study discusses the implications of this classification within the framework of the phenomenological theory and verifies several predictions through numerical simulations. The analysis reveals that sorting is most efficient when the number of sorting domains is close to a minimum, and introduces an operational definition of the critical size of sorting domains to aid in the analysis of experimental data. Comparison with experimental results suggests that the statistical properties of productive and unproductive domains inferred from experimental data align with those predicted by numerical simulations, supporting the hypothesis that molecular sorting is driven by a phase separation process.
Review
Cell Biology
Chayanika Gundu, Vijay Kumar Arruri, Poonam Yadav, Umashanker Navik, Ashutosh Kumar, Veda Sudhir Amalkar, Ajit Vikram, Ravinder Reddy Gaddam
Summary: Endocytosis is a crucial mechanism for cells to perform their functions, and it involves various mechanisms and regulatory proteins. Dynamin, a GTPase, plays a vital role in forming endocytic vesicles and regulating the process. Apart from dynamin, there are other GTPases, membrane proteins, and secondary messengers involved in dynamin-independent endocytosis. The determination of the specific path of endocytosis is complex and challenging to understand.
Article
Physics, Multidisciplinary
Mainak Chatterjee, Arkya Chatterjee, Amitabha Nandi, Anirban Sain
Summary: Contraction of the cytokinetic ring during cell division leads to physical partitioning of a eukaryotic cell into two daughter cells. This process involves flows of actin filaments and myosin motors in the growing membrane interface at the midplane of the dividing cell. The arrangement of actomyosin filaments and the resulting active stresses influence the flow, and the contraction process of the ring exhibits both stable and unstable modes.
PHYSICAL REVIEW LETTERS
(2022)
Article
Virology
Qiongyi Li, Yang Liu, Shujuan Xu, Kexue Zhao, Ying Ling, Rongxiu Liu, Amjad Ali, Jialin Bai
Summary: This study uncovered that caveolin-1, dynamin, and actin-dependent endocytosis pathways are necessary for EMCV infection in vitro. Overexpression of caveolin-1 was positively correlated with EMCV infection, and caveolin-1 was found to be required at the early stage of EMCV infection through confocal microscopy analysis and internalization assay.
Review
Oncology
Paulius Gibieza, Vilma Petrikait
Summary: Actin plays a critical role in regulating cell division and its dynamics control is altered in malignancy, affecting the success of cell division process.
AMERICAN JOURNAL OF CANCER RESEARCH
(2021)
Article
Cell Biology
Mamata Malla, Thomas D. Pollard, Qian Chen
Summary: This study used low concentrations of GFP-Lifeact to investigate the amount of polymerized actin in the contractile rings of live fission yeast cells. The results showed that adf1-M3 mutant cells accumulated twice the amount of polymerized actin in their contractile rings compared to wild-type cells, along with an increase in type II myosins.
MOLECULAR BIOLOGY OF THE CELL
(2022)
Article
Cell Biology
Md. Shahabe Uddin Talukder, Mst. Shaela Pervin, Md. Istiaq Obaidi Tanvir, Koushiro Fujimoto, Masahito Tanaka, Go Itoh, Shigehiko Yumura
Article
Cell Biology
Masahito Tanaka, Koushiro Fujimoto, Shigehiko Yumura
FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY
(2020)
Editorial Material
Cell Biology
Masahito Tanaka, Yuta Shimamoto
Summary: The study shows using sophisticated imaging techniques and Xenopus egg extracts that the mass density of the spindle is similar to the surrounding cytoplasm, contrary to previous beliefs.
DEVELOPMENTAL CELL
(2021)
Article
Cell Biology
Md. Istiaq Obaidi Tanvir, Go Itoh, Hiroyuki Adachi, Shigehiko Yumura
Summary: The study observed wound repair in dividing cells for the first time and found dynamic changes of myosin II during cell membrane repair. It was discovered that myosin II is not essential for cell wound repair, and a novel mechanism for its delocalization from the cortex through phosphorylation was proposed. Additionally, the disappearance of several furrow-localizing proteins upon wounding was observed, indicating potential mechanisms for myosin dynamics during wound repair.
Article
Cell Biology
Masashi Mori, Tatsuma Yao, Tappei Mishina, Hiromi Endoh, Masahito Tanaka, Nao Yonezawa, Yuta Shimamoto, Shigenobu Yonemura, Kazuo Yamagata, Tomoya S. Kitajima, Masahito Ikawa
Summary: The study reveals that RanGTP and F-actin dynamics prevent egg-sperm fusion in proximity to maternal chromosomes, protecting paternal chromosomes from maternal meiosis and preventing aneuploidy in zygotes.
JOURNAL OF CELL BIOLOGY
(2021)
Article
Multidisciplinary Sciences
Masahito Tanaka, Toshiko Kitanishi-Yumura, Shigehiko Yumura
Summary: This study accurately measured the total cell surface area of Dictyostelium cells throughout the cell cycle, showing an exponential increase in surface area during interphase, with cell size regulation primarily governed by the adder or near-adder model. This dynamic adder model suggests that cell membrane turnover plays a key role in maintaining cell size homeostasis during interphase.
SCIENTIFIC REPORTS
(2021)
Article
Multidisciplinary Sciences
Tsukasa Nakatoh, Takuji Osaki, Sohma Tanimoto, Md Golam Sarowar Jahan, Tomohisa Kawakami, Kentaro Chihara, Nobuyuki Sakai, Shigehiko Yumura
Summary: Two innovative methods are described for fabricating a substrate that enables the control of cell adhesion to specific areas. These methods effectively confine cells within the adhesive region and allow for the observation of new aspects of cell behavior.
Article
Biochemistry & Molecular Biology
Koushiro Fujimoto, Kentaro Nakano, Hidekazu Kuwayama, Shigehiko Yumura
Summary: The study demonstrates that GmfA plays a crucial role in cell migration, with its absence leading to changes in cell morphology and motility characteristics.
Article
Multidisciplinary Sciences
Tatsuya Fukuyama, Lucan Yan, Masahito Tanaka, Megumi Yamaoka, Kei Saito, Shih-Chieh Ti, Chung-Chi Liao, Kuo-Chiang Hsia, Yusuke T. Maeda, Yuta Shimamoto
Summary: The spindle is a dynamic intracellular structure essential for chromosome segregation during cell division. It can exhibit varied shape morphologies through nonrandom, bistable self-organization paths. The emergence of different spindle shapes is influenced by both physical and molecular factors.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Cell Biology
Shigehiko Yumura, Md Shahabe Uddin Talukder, Mst Shaela Pervin, Md Istiaq Obaidi Tanvir, Takashi Matsumura, Koushiro Fujimoto, Masahito Tanaka, Go Itoh
Summary: This study investigated the mechanism of actin accumulation at the wound site and the involvement of related proteins and signaling pathways in wound repair.
Article
Cell Biology
Shigehiko Yumura, Masaki Nakano, Aika Honda, Yuuki Hashimoto, Tomo Kondo
Summary: Cyclic guanosine 3',5'-monophosphate (cGMP) is an important second messenger involved in various physiological functions. In chemotactic Dictyostelium cells, intracellular cGMP (cGMPi) was visualized using the fluorescent probe D-Green cGull. The responses of cGMPi propagated in a wave-like fashion from the aggregation center during the aggregation stage, and its oscillation was synchronized with other second messengers, such as cAMP and Ca2+. Increased cGMPi concentration induced a transient shuttle of myosin II, suggesting a direct link between cGMP signaling and myosin II dynamics.
JOURNAL OF CELL SCIENCE
(2023)
Article
Cell Biology
Akiko Okada, Shigehiko Yumura
Summary: Accurate placement of the cleavage furrow is crucial for successful cell division. Dictyostelium cells were used to validate previous models, and it was found that the rotational movements of the mitotic spindles stopped when the spindle elongated. Astral microtubules reaching and fixing the spindle axis caused cell elongation and division along the spindle axis.
Article
Cell Biology
Takeru Arima, Keisuke Okita, Shigehiko Yumura
Summary: In this study, transmission electron microscopy was used to observe actin and myosin II filaments in the contractile rings of dividing Dictyostelium cells. The development of a novel method allowed for the synchronization of cytokinesis and high-frequency visualization of dividing cells undergoing cytokinesis. The length and alignment of individual filaments within the contractile rings were examined, revealing the gradual decrease in actin filament length and the perpendicular reorientation of actin and myosin II filaments during furrow constriction. Myosin II was found to regulate both the lengths and alignments of actin filaments, while dynamin-like protein A and cortexillins were involved in regulating filament length and alignment, respectively.