{"title":"Chromosome Segregation in Closed Mitosis Under an Excess of Nuclear Envelope","authors":"Noelia Rodríguez-Herrera, Silvia Santana-Sosa, Sara Medina-Suárez, Samantha Morais-Armas, Emiliano Matos-Perdomo, Félix Machín","doi":"10.1111/boc.70011","DOIUrl":"https://doi.org/10.1111/boc.70011","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Two major types of cell division occur in eukaryotic cells regarding the dismantlement or not of the nuclear envelope (NE) in mitosis, open and closed mitosis, respectively. In the budding yeast <i>Saccharomyces cerevisiae</i>, the prototypical model for closed mitosis, the Nem1-Spo7 phosphatase complex, which regulates lipid metabolism, plays a key role in coordinating NE expansion throughout the cell cycle. Indeed, Nem1 depletion leads to abnormal NE evaginations in interphase, which protrude the ribosomal DNA (rDNA) and the nucleolus. However, the specific impact of these NE and chromosome organization abnormalities during chromosome segregation in anaphase remains poorly understood.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Our study investigated chromosome segregation and NE dynamics during closed mitosis in relation to the presence or absence of Nem1. Nem1 was depleted by means of the auxin degron system. Nem1 depletion led to the formation of chromatin protrusions in interphase, particularly at the rDNA locus, as it has been reported before for <i>nem1</i> mutants. These protrusions persisted into anaphase and were associated with delayed recoiling of the rDNA-bearing chromosome XII right arm, resulting in lagging chromatin during late anaphase. Additionally, cells can maintain nucleus-vacuole junctions (NVJs) during anaphase, suggesting that vacuoles may play a role in shaping NE morphology during chromosome segregation.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>Our findings suggest that the Nem1-Spo7/lipin regulation of the NE size is crucial for the timely segregation of the rDNA-bearing chromosome during closed mitosis. Thus, the NE homeostasis actively contributes to chromosome segregation and the spatial organization of chromosomes in subsequent cell cycles. In addition, the persistent association between the NE and vacuoles in anaphase further underscores how cumbersome organelle interactions can become during closed mitosis, opening inspiring research avenues.</p>\u0000 </section>\u0000 </div>","PeriodicalId":8859,"journal":{"name":"Biology of the Cell","volume":"117 5","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/boc.70011","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144091591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ashish Agrahari, Km. Archana, Nittu Singh, Akshay Joshi, Budai S. Vivek Vinod, Sourav Haldar, Krishan Gopal Thakur, Raj Kamal Tripathi
{"title":"Identification and Characterization of a Novel Protein–Protein Interaction Among SARS-CoV-2 Nucleocapsid, Host SFPQ, and hnRNP U and Its Potential Role in Virus Replication","authors":"Ashish Agrahari, Km. Archana, Nittu Singh, Akshay Joshi, Budai S. Vivek Vinod, Sourav Haldar, Krishan Gopal Thakur, Raj Kamal Tripathi","doi":"10.1111/boc.70008","DOIUrl":"https://doi.org/10.1111/boc.70008","url":null,"abstract":"<div>\u0000 \u0000 <p>SARS-CoV-2 has led to significant global health and economic challenges and caused the COVID-19 pandemic. The ability of the virus to replicate adeptly within host cells is critical for its pathogenicity. The structural nucleocapsid (N) protein of SARS-CoV-2 packages newly synthesized viral RNA with the association of various host proteins that may contribute to different functions in maintaining a productive viral life cycle. In this study, we report the identification and characterization of host proteins SFPQ and hnRNP U interacting with SARS-CoV-2 N protein in both N-transfected cells and virus-infected cells, forming a hetero-trimeric protein complex. Using carefully designed peptides that span the length of N protein and competitive inhibition, we identified the interacting domains at N protein that interact with SFPQ and hnRNP U. Our results constitute the first report that the characterized N protein and host SFPQ and hnRNP U form a hetero-trimeric protein complex in both N transfected cells and virus-infected cells. Utilizing competitive peptides, we were able to disrupt the hetero-trimeric protein complex in virus-infected cells, leading to reduction in viral replication. These results clearly demonstrate that N-SFPQ-hnRNP U hetero-trimeric protein complex formation is found in SARS-CoV-2 infected cells that regulate viral replication. Our findings suggest that the protein–protein interaction (PPI) between N-SFPQ-hnRNP U hetero-trimeric protein complexes could be a novel drug target for developing therapeutics against COVID-19.</p>\u0000 </div>","PeriodicalId":8859,"journal":{"name":"Biology of the Cell","volume":"117 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143857104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Melina Thetiot, Sébastien Sart, Delphine Cussigh, Marion Coolen, Charles N. Baroud, Laure Bally-Cuif
{"title":"Generation and Pharmacological Manipulation of 3D-Spheroid Cultures Derived From Zebrafish Adult Neural Stem Cells in a Droplet-Based Microfluidic Platform","authors":"Melina Thetiot, Sébastien Sart, Delphine Cussigh, Marion Coolen, Charles N. Baroud, Laure Bally-Cuif","doi":"10.1111/boc.70007","DOIUrl":"https://doi.org/10.1111/boc.70007","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> AIMS</h3>\u0000 \u0000 <p>Neural stem cells (NSCs) generate neurons and glia in the adult vertebrate brain, crucial for tissue maintenance and plasticity. They balance neurogenesis with self-renewal, regulated through transitions between quiescence, activation, and lineage progression. The molecular and cellular mechanisms behind these processes remain incompletely understood.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> METHODS</h3>\u0000 \u0000 <p>Here, we describe a protocol to isolate and expand NSCs from the adult zebrafish pallium, a major NSC niche. We present the procedures to propagate primary cultures of NSCs, followed by the generation of 3D spheres and their regulation in a droplet microfluidic platform. We then detail the procedure to analyze adult NSC fate within the 3D spheroids following drug treatment.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> RESULTS</h3>\u0000 \u0000 <p>We show that 7 µL droplets are sufficient to allow the formation of size-controlled 3D spheroids, in which NSCs sustain self-renewal and are able to balance quiescence and activation. We outline potential applications, including investigation of factors involved in adult NSC activation and monitoring of their soluble environment, for which a confined culture system is advantageous.</p>\u0000 </section>\u0000 </div>","PeriodicalId":8859,"journal":{"name":"Biology of the Cell","volume":"117 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143852965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Lipid Droplet in Lipodystrophy and Neurodegeneration","authors":"Priyatama Behera, Monalisa Mishra","doi":"10.1111/boc.70009","DOIUrl":"https://doi.org/10.1111/boc.70009","url":null,"abstract":"<div>\u0000 \u0000 <p>Lipid droplets are ubiquitous yet distinct intracellular organelles that are gaining attention for their uses outside of energy storage. Their formation, role in the physiological function, and the onset of the pathology have been gaining attention recently. Their structure, synthesis, and turnover play dynamic roles in both lipodystrophy and neurodegeneration. Factors like development, aging, inflammation, and cellular stress regulate the synthesis of lipid droplets. The biogenesis of lipid droplets has a critical role in reducing cellular stress. Lipid droplets, in response to stress, sequester hazardous lipids into their neutral lipid core, preserving energy and redox balance while guarding against lipotoxicity. Thus, the maintenance of lipid droplet homeostasis in adipose tissue, CNS, and other body tissues is essential for maintaining organismal health. Insulin resistance, hypertriglyceridemia, and lipid droplet accumulation are the severe metabolic abnormalities that accompany lipodystrophy-related fat deficit. Accumulation of lipid droplets is detected in almost all neurodegenerative diseases like Alzheimer's, Parkinson's, Huntington's, and Hereditary spastic paraplegia. Hence, the regulation of lipid droplets can be used as an alternative approach to the treatment of several diseases. The current review summarizes the structure, composition, biogenesis, and turnover of lipid droplets, with an emphasis on the factors responsible for the accumulation and importance of lipid droplets in lipodystrophy and neurodegenerative disease.</p>\u0000 </div>","PeriodicalId":8859,"journal":{"name":"Biology of the Cell","volume":"117 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143845912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Integration of Organoids With CRISPR Screens: A Narrative Review","authors":"Rushikesh Mukhare, Khushboo A. Gandhi, Anushree Kadam, Aishwarya Raja, Ankita Singh, Mrudula Madhav, Rohan Chaubal, Shwetali Pandey, Sudeep Gupta","doi":"10.1111/boc.70006","DOIUrl":"https://doi.org/10.1111/boc.70006","url":null,"abstract":"<p>Organoids represent a significant advancement in disease modeling, demonstrated by their capacity to mimic the physiological/pathological structure and functional characteristics of the native tissue. Recently CRISPR/Cas9 technology has emerged as a powerful tool in combination with organoids for the development of novel therapies in preclinical settings. This review explores the current literature on applications of pooled CRISPR screening in organoids and the emerging role of these models in understanding cancer. We highlight the evolution of genome-wide CRISPR gRNA library screens in organoids, noting their increasing adoption in the field over the past decade. Noteworthy studies utilizing these screens to investigate oncogenic vulnerabilities and developmental pathways in various organoid systems are discussed. Despite the promise organoids hold, challenges such as standardization, reproducibility, and the complexity of data interpretation remain. The review also addresses the ideas of assessing tumor organoids (tumoroids) against established cancer hallmarks and the potential of studying intercellular cooperation within these models. Ultimately, we propose that organoids, particularly when personalized for patient-specific applications, could revolutionize drug screening and therapeutic approaches, minimizing the reliance on traditional animal models and enhancing the precision of clinical interventions.</p>","PeriodicalId":8859,"journal":{"name":"Biology of the Cell","volume":"117 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/boc.70006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143826697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"How to Study the Mechanobiology of Intestinal Epithelial Organoids? A Review of Culture Supports, Imaging Techniques, and Analysis Methods","authors":"Léa Magne, Florian Bugarin, Audrey Ferrand","doi":"10.1111/boc.70003","DOIUrl":"https://doi.org/10.1111/boc.70003","url":null,"abstract":"<p>Mechanobiology studies how mechanical forces influence biological processes at different scales, both in homeostasis and in pathology. Organoids, 3D structures derived from stem cells, are particularly relevant tools for modeling tissues and organs in vitro. They currently constitute one of the most suitable models for mechanobiology studies. This review provides an overview of existing or applicable approaches to organoids for mechanical studies. We first present the different types of culture supports, including hydrogels and organ-on-chip. We then discuss advanced imaging techniques, particularly suitable for studying the physical properties of cells, allowing the visualization of mechanical forces and cellular responses. We also describe the approaches and tools available to observe the organoids by microscopy. Finally, we present analytical methods, including computational models and biophysical measurement approaches, which facilitate the quantification of mechanical interactions. This review aims to provide the most comprehensive overview possible of the methods, instrumentations, and tools available to conduct a mechanobiological study on organoids.</p>","PeriodicalId":8859,"journal":{"name":"Biology of the Cell","volume":"117 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/boc.70003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143826696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Clara Manesco, Thierry Cloitre, Marta Martin, Yannick Nicolas Gerber, Florence Evelyne Perrin, Oscar Saavedra-Villanueva, Csilla Gergely
{"title":"Undergrowth Collagen Fibers Analysis by Fingerprint Enhancement Method","authors":"Clara Manesco, Thierry Cloitre, Marta Martin, Yannick Nicolas Gerber, Florence Evelyne Perrin, Oscar Saavedra-Villanueva, Csilla Gergely","doi":"10.1111/boc.70001","DOIUrl":"https://doi.org/10.1111/boc.70001","url":null,"abstract":"<p>Collagen is a key protein in mammals that maintains structural integrity within tissues. A failure in fibrillar collagen reorganization can induce cancer or fibrosis formation, such as in spinal cord injury (SCI), where the healing process after the initial trauma leads to the formation of scar tissue, which includes fibrosis. As there is no current treatment targeting the fibrotic process directly, a better understanding of collagen properties can thus help to apprehend malignant states.</p><p>Characterization of collagen fibers has been widely explored on second-harmonic generation (SHG) images, due to the label-free nature of the SHG imaging technique. It has been performed with various fibers extraction methods such as curvelet transform (CT) implemented in the open-source software CurveAlign. However, when it comes to investigating undergrowth collagen fibers (collagen fibers that are still under reorganization) as observed in SCI, the CT method becomes complex to tune for nonadvanced users in order to properly segment the fibers. To improve collagen detection in the case of undergrowth fibers, we propose a methodology based on the fingerprint enhancement (FP-E) algorithm that requires fewer user input parameters and is less time-consuming. Our method was extensively tested on SHG data from injured spinal cord samples.</p><p>We obtained metrics that depicted changes in collagen organization over time, particularly a significant increase in fiber density, demonstrating the FP-E algorithm was properly adapted to address the evolution of collagen properties after SCI. Besides the simpler tuning of the method compared to commonly used software, the combination with further characterization of the extracted fibers could lead to consider fibrillar collagen as a biomarker in diseases where fibers are under development. The FP-E algorithm is provided in the article.</p>","PeriodicalId":8859,"journal":{"name":"Biology of the Cell","volume":"117 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/boc.70001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143793604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hye-Young Yoon, Jonah Unthank, Sandeep Pallikkuth, Pei-Wen Chen, Paul A. Randazzo
{"title":"Actin Binding to the BAR Domain and Arf GAP Activity of ASAP1 Coordinately Control Actin Stress Fibers and Focal Adhesions","authors":"Hye-Young Yoon, Jonah Unthank, Sandeep Pallikkuth, Pei-Wen Chen, Paul A. Randazzo","doi":"10.1111/boc.70005","DOIUrl":"https://doi.org/10.1111/boc.70005","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Actin stress fibers (SFs) and focal adhesions (FAs) are dynamic structures crucial to a range of cell behaviors including cell morphology, cell migration, proliferation, survival, and differentiation. The Arf GAP ASAP1 affects both SFs and FAs. Here, we test the hypothesis that two domains with distinct biochemical activities in ASAP1, the BAR domain that binds actin and nonmuscle myosin 2 (NM2) and the Arf GAP domain, which is necessary for inducing hydrolysis of GTP bound to Arf, coordinately regulate the structures.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>We found that ASAP1 associated with bundled actin, including SFs, colocalizing with α-actinin and nonmuscle myosin 2A (NM2A), and with paxillin in FAs. Reducing ASAP1 expression altered both SFs and FAs in four cell lines that we examined. The effects of reducing ASAP1 expression could be reversed by ectopic expression of ASAP1. Reduced expression of Arf5, a substrate for ASAP1, or expression of either dominant negative or GTPase deficient mutants of Arf5, affected SFs and FAs similarly to ASAP1 knockdown. Both an active GAP domain and a BAR domain contained in the same ASAP1 polypeptide were necessary to maintain FAs and SFs.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions and Significance</h3>\u0000 \u0000 <p>Taken together, the results support the idea that ASAP1 coordinates the maintenance of FAs and SFs through integrated function of the BAR and GAP domains. We speculate that ASAP1 regulates SFs and their interaction with FAs through direct binding to components of the actin cytoskeleton. We discuss hypotheses related to this Arf-dependent activity of ASAP1 and propose the function of ASAP1 is not control of Arf•GTP levels.</p>\u0000 </section>\u0000 </div>","PeriodicalId":8859,"journal":{"name":"Biology of the Cell","volume":"117 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/boc.70005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143793667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Phospholipid Biosynthesis: An Unforeseen Modulator of Nuclear Metabolism","authors":"Hong Qiu, Cunqi Ye","doi":"10.1111/boc.70002","DOIUrl":"https://doi.org/10.1111/boc.70002","url":null,"abstract":"<div>\u0000 \u0000 <p>Glycerophospholipid biosynthesis is crucial not only for providing structural components required for membrane biogenesis during cell proliferation but also for facilitating membrane remodeling under stress conditions. The biosynthetic pathways for glycerophospholipid tails, glycerol backbones, and diverse head group classes intersect with various other metabolic processes, sharing intermediary metabolites. Recent studies have revealed intricate connections between glycerophospholipid synthesis and nuclear metabolism, including metabolite-mediated crosstalk with the epigenome, signaling pathways that govern genome integrity, and CTP-involved regulation of nucleotide and antioxidant biosynthesis. This review highlights recent advances in understanding the functional roles of glycerophospholipid biosynthesis beyond their structural functions in budding yeast and mammalian cells. We propose that glycerophospholipid biosynthesis plays an integrative role in metabolic regulation, providing a new perspective on lipid biology.</p>\u0000 </div>","PeriodicalId":8859,"journal":{"name":"Biology of the Cell","volume":"117 3","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143689946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}