Article
Biology
Maikel Castellano-Pozo, Georgios Sioutas, Consuelo Barroso, Josh P. Prince, Pablo Lopez-Jimenez, Joseph Davy, Angel-Luis Jaso-Tamame, Oliver Crawley, Nan Shao, Jesus Page, Enrique Martinez-Perez
Summary: This study reveals the distinct roles of REC-8 and COH-3/4 complexes during meiosis. REC-8 complexes provide sister chromatid cohesion and DNA repair, while COH-3/4 complexes control higher-order chromosome structure.
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.
Article
Biology
Nicolas Macaisne, Laura Bellutti, Kimberley Laband, Frances Edwards, Laras Pitayu-Nugroho, Alison Gervais, Thadshagine Ganeswaran, Helene Geoffroy, Gilliane Maton, Julie C. Canman, Benjamin Lacroix, Julien Dumont
Summary: During cell division, the microtubule-based spindle plays a crucial role in chromosome segregation. The interaction between spindle microtubules and kinetochores is essential for the proper alignment and segregation of chromosomes. This study focuses on a kinetochore module called the BHC module, which consists of BUB-1, HCP-1/2, and CLS-2, and shows that it stabilizes microtubules, promoting spindle formation and accurate chromosome segregation.
Article
Biology
Samuel J. P. Taylor, Laura Bel Borja, Flavie Soubigou, Jack Houston, Dhanya K. Cheerambathur, Federico Pelisch
Summary: Phosphorylation is an important post-translational modification used for regulating protein localization and activity. Polo-like kinase 1 (PLK-1) is crucial for mitotic and meiotic cell divisions, but its specific roles and regulation in meiosis have been unclear. In this study, using C. elegans oocytes, we demonstrate that PLK-1 is involved in spindle assembly, chromosome alignment and segregation, and polar body extrusion during meiosis I. We also uncover the mechanisms of PLK-1 recruitment to meiotic chromosomes. Our findings reveal the essential functions of PLK-1 in oocyte meiosis and provide insights into its targeting mechanisms.
Review
Genetics & Heredity
Spencer G. Gordon, Ofer Rog
Summary: The successful delivery of genetic material to gametes relies on tightly regulated interactions between parental chromosomes, which are brought in close proximity along their length by a conserved chromosomal interface called the synaptonemal complex (SC). Despite known components, the interfaces responsible for SC assembly remain unknown. This study surveys findings from various model systems, with a focus on insights gained from the nematode C. elegans, to synthesize our current understanding of SC structure, dynamics, and biophysical properties, and propose mechanisms for SC assembly.
Article
Biotechnology & Applied Microbiology
Eui-Hwan Choi, Seobin Yoon, Young Eun Koh, Tae Kyung Hong, Jeong Tae Do, Bum-Kyu Lee, Yoonsoo Hahn, Keun P. Kim
Summary: The study reveals the functional roles of meiosis-specific cohesin complexes in mitotic chromosomes and their impact on chromosomal organization and the mitotic program in embryonic stem cells. The delicate balance between mitotic and meiotic cohesins is crucial for maintaining proper chromosome structure and function in ESCs.
Article
Genetics & Heredity
Filip Pajpach, Linda Shearwin-Whyatt, Frank Gruetzner
Summary: Chromosome segregation is a complex process involving multiple genes and complexes that are evolutionarily conserved in mammals but show functional diversification, reflecting lineage-specific characteristics. Genes involved in chromosome segregation in monotremes have been shown to be preserved and functionally active, with specific evolutionary adaptations observed in different species.
Article
Genetics & Heredity
Ting Gong, Francis J. McNally
Summary: Errors in chromosome segregation during meiosis are a major cause of aneuploidy. Crossovers are crucial for accurate chromosome alignment and partitioning, as they hold homologous chromosomes together. However, Caenorhabditis elegans zim-2 mutants with crossover defects on chromosome V have fewer dead embryos than expected, especially in males. This discrepancy can be explained by the presence of redundant mechanisms to compensate for crossover loss, a higher production of euploid gametes, and the viability and fertility of trisomy of chromosome V. Additionally, live imaging showed that univalents can segregate independently of homology.
Article
Biology
Gabriel Cavin-Meza, Michelle M. Kwan, Sarah M. Wignall
Summary: Multiple motors work synchronously to establish and maintain the bipolarity of oocyte spindles in the absence of centrosomes.
Article
Biochemistry & Molecular Biology
Yulia Gryaznova, Leonor Keating, Sandra A. Touati, Damien Cladiere, Warif El Yakoubi, Eulalie Buffin, Katja Wassmann
Summary: This research explores the separation of sister kinetochores and removal of cohesin during meiosis, revealing that the initial separation of sister kinetochores actually occurs during meiosis I, not meiosis II as previously thought. This indicates that whether centromeric cohesin is removed or not is determined by the kinetochore structure prior to meiosis II.
Article
Reproductive Biology
Adelita D. Mendoza, Aaron Sue, Olga Antipova, Stefan Vogt, Teresa K. Woodruff, Sarah M. Wignall, Thomas O'Halloran
Summary: The dynamic flux of zinc is essential for meiotic progression in C. elegans embryos and is a conserved feature of germ cell development in a variety of metazoa.
BIOLOGY OF REPRODUCTION
(2022)
Article
Chemistry, Physical
Grace A. DeSalvo, Grayson R. Hoy, Isabelle M. Kogan, John Z. Li, Elise T. Palmer, Emilio Luz-Ricca, Paul Scemama de Gialluly, Kristin L. Wustholz
Summary: This study introduces a blinking-based multiplexing approach to differentiate spectrally overlapped emitters. By analyzing the blinking dynamics of fluorescent probes on glass, a blinking metric with 93.5% classification accuracy is obtained. Furthermore, using a deep learning algorithm for classification, up to 96.6% accuracy is achieved.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Cell Biology
Hanna Achache, Roni Falk, Noam Lerner, Tsevi Beatus, Yonatan B. Tzur
Summary: Research has found that in the aging process of worms, germline proliferation decreases after ovulation stops, while apoptosis continues, leading to a gradual reduction in germ cell numbers. Oocyte quality declines during aging, and MAPK signaling controls germline aging.
Article
Biology
Jonay Garcia-Luis, Helene Bordelet, Agnes Thierry, Romain Koszul, Luis Aragon
Summary: This study reveals that degradation of cohesin during anaphase onset leads to aberrant chromatid segregation in yeast cells. Hi-C analysis of segregating chromatids shows that depletion of cohesin results in loss of intrachromatid organization. Surprisingly, cleavage of cohesin through specific methods does not significantly disrupt chromatid organization during anaphase, explaining successful bulk segregation.
Article
Multidisciplinary Sciences
Manoj Kumar, Lavlesh Pensia, Raj Kumar
Summary: A new configuration of a digital holographic system is proposed to double the camera field-of-view (FOV) of the existing setup. This is achieved by multiplexing the object beam with two different spatial frequencies using a Fresnel bi-prism. The feasibility of the proposed system is demonstrated experimentally, and its limitations and a method to overcome them are discussed. The system has practical applications in microscopy and optical metrology.
SCIENTIFIC REPORTS
(2022)
Article
Chemistry, Multidisciplinary
Bowen Wang, Michael Xiong, Josephine Susanto, Xue Li, Wai-Yee Leung, Ke Xu
Summary: We propose a strategy to optimize the photoswitching behavior of rhodamines for (d)STORM super-resolution microscopy. By replacing the benzene ring with a permanently charged 1,3-disubstituted imidazolium, the resulting dyes show enhanced photoswitching capability and exhibit excellent performance in (d)STORM with fast on-off switching, long-lasting blinking, and bright single-molecule emission. Our method achieves high-quality (d)STORM images under green excitation that are comparable to those obtained using ideal red-excited dyes, even for challenging structures like the mammalian actin cytoskeleton. We also demonstrate high-quality two-color three-dimensional (d)-STORM.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Cell Biology
Rui Yan, Kun Chen, Bowen Wang, Ke Xu
Summary: A highly elongated tubular ER-Golgi intermediate compartment (t-ERGIC) that selectively expedites the ER-to-Golgi transport for soluble cargoes of the receptor SURF4 has been discovered. The t-ERGIC has a distinctive elongated and thinned shape, and is marked by the small GTPases Rabl A/B instead of the canonical ERGIC marker ERGIC-53. It accelerates the trafficking of SURF4-bound cargoes with its large surface-to-volume ratio, high intracellular traveling speeds, and ER-Golgi recycling capabilities.
DEVELOPMENTAL CELL
(2022)
Article
Chemistry, Multidisciplinary
Yunqi Li, Bowen Wang, Wan Li, Ke Xu
Summary: This study reports that acidic solutions can induce the fast generation of solution-enclosing blisters on monolayer and few-layer graphene on silicon and glass substrates. The graphene blisters are nanoscale to micrometer-sized and are universally generated on hydrophilic surfaces. The blisters are highly dynamic and can be modulated by solution osmotic pressure.
Article
Chemistry, Multidisciplinary
Alexander A. Choi, Ha H. Park, Kun Chen, Rui Yan, Wan Li, Ke Xu
Summary: Recent studies have sparked debate over whether catalytic reactions enhance the diffusion coefficients of enzymes. Through high statistical analysis, it has been found that catalytic reactions do not affect the diffusion properties of hydrogenase, urease, aldolase, and alkaline phosphatase.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Multidisciplinary Sciences
Bowen Wang, Zhiheng Zhao, Michael Xiong, Rui Yan, Ke Xu
Summary: The endoplasmic reticulum (ER) is a versatile organelle with distinct forms of tubules, regulated by Rtn4 and Climp63, that together form a ribbon-like structure of well-defined width.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Multidisciplinary Sciences
Meiyan Jin, Cyna Shirazinejad, Bowen Wang, Amy Yan, Johannes Schoneberg, Srigokul Upadhyayula, Ke Xu, David G. Drubin
Summary: This study investigates the organization of actin networks at clathrin-mediated endocytosis (CME) sites and how actin assembly is regulated. The findings show that actin assembles preferentially at stalled CME sites, where it exerts an asymmetric force to pull vesicles into the cell. N-WASP and the Arp2/3 complex are recruited to one side of CME sites for stimulating asymmetric actin assembly.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Yiming Li, Wei Shi, Sheng Liu, Ivana Cavka, Yu-Le Wu, Ulf Matti, Decheng Wu, Simone Koehler, Jonas Ries
Summary: Global fitting algorithm globLoc for multi-channel SMLM significantly improves localization precision and color assignment, by extracting maximum information from correlated signals in multi-channel data through flexible parameter sharing and modeling.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Wojciech M. Smigiel, Luca Mantovanelli, Dmitrii S. Linnik, Michiel Punter, Jakob Silberberg, Limin Xiang, Ke Xu, Bert Poolman
Summary: This study analyzed the structure of the cytoplasm in Escherichia coli by performing single-molecule displacement mapping on native cytoplasmic proteins. It found that protein diffusion at the poles is consistently slower than in the center of the cell and that the diffusion coefficient scales with the mass of the used probes, while other parameters do not correlate with protein mobility.
Article
Chemistry, Multidisciplinary
Ilya O. Aparin, Rui Yan, Remi Pelletier, Alexander A. Choi, Dmytro I. Danylchuk, Ke Xu, Andrey S. Klymchenko
Summary: This study proposes a concept of ON/OFF switchable probes for super-resolution fluorescence microscopy based on bright cyanine dyes. The new probes provide higher brightness and slower diffusion at the cell surface, improving the localization precision. The study validated the concept and demonstrated the observation of nanoscale cellular structures with enhanced dynamics.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Multidisciplinary Sciences
Ivana Cavka, Rory M. Power, Dietrich Walsh, Timo Zimmermann, Simone Koehler
Summary: During meiosis, the assembly of the synaptonemal complex (SC) is crucial for the recognition and adherence of homologous chromosomes. The molecular structure of the SC can be studied using electron microscopy and fluorescence microscopy techniques, with super-resolution methods providing higher resolution. Observing the complex in a close-to-native environment is important for maintaining its structure and interactions.
JOVE-JOURNAL OF VISUALIZED EXPERIMENTS
(2022)
Article
Chemistry, Physical
Ha H. Park, Alexander A. Choi, Ke Xu
Summary: By using expansion microscopy, we investigated the size-dependent suppression of molecular diffusivity in hydrogel nanomatrices with controlled meshwork size. Our research demonstrated that larger molecules experience more impeded diffusion within a fixed meshwork size, and diffusion is progressively suppressed as the meshwork size decreases, particularly for larger molecules. We also found that the obstruction of diffusion caused by the meshwork is independent of the suppression of diffusion due to increased solution viscosities. These mechanisms can scale down molecular diffusivity to produce diffusion slowdown in complex systems like cells.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Chemistry, Multidisciplinary
Limin Xiang, Rui Yan, Kun Chen, Wan Li, Ke Xu
Summary: Using single-molecule displacement/diffusivity mapping (SMdM), we analyzed the diffusion of a typical fluorescent protein (FP) in living mammalian cells at nanoscale resolution. We found that the diffusion coefficients in the endoplasmic reticulum (ER) and mitochondrion are about 40% of that in the cytoplasm, with higher spatial inhomogeneities in the cytoplasm. Furthermore, we discovered that positive net charges impede diffusions in the ER lumen and mitochondrial matrix, while negative net charges do not.
Article
Biology
Ha H. Park, Bowen Wang, Suhong Moon, Tyler Jepson, Ke Xu
Summary: This study presents a machine-learning-enabled approach called Pix2D, which extracts the diffusion coefficient D directly from single molecule images and enables high-resolution spatial mapping of D.
COMMUNICATIONS BIOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Changdong He, Chun Ying Wu, Wan Li, Ke Xu
Summary: The study reveals nanoscale heterogeneities in FUS condensates and their evolution over aging using multidimensional super-resolution microscopy tools. Hydrophobic nanodomains and amyloid aggregates are identified at the condensate surface, which significantly impede local diffusion. These nanoaggregates progressively expand on the condensate surface upon aging or mechanical shears, leading to a growing low-diffusivity shell while maintaining diffusion in the condensate interior.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Optics
Vu Nguyen, Wan Li, Joel Ager, Ke Xu, Hayden Taylor
Summary: Optical reflectance imaging is a simple and fast technique for characterizing 2D materials. It can reveal the interlayer coupling in stacked MoS2 and WS(2) bilayers through reflectance contrast. The determination of interlayer coupling requires optimization of illumination wavelength and SiO2 film thickness. This approach enables quick characterization of constructed 2D material systems.
