Molecular Biology of the Cell最新文献_第2页

The centromere bottlebrush requires a multi-microtubule attachment. 着丝粒瓶刷需要多微管连接。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-06-01 Epub Date: 2025-04-23 DOI: 10.1091/mbc.E25-02-0050

Daniel Kolbin, John Stanton, Aryan Kokkanti, Elaine Yeh, Kerry Bloom

{"title":"The centromere bottlebrush requires a multi-microtubule attachment.","authors":"Daniel Kolbin, John Stanton, Aryan Kokkanti, Elaine Yeh, Kerry Bloom","doi":"10.1091/mbc.E25-02-0050","DOIUrl":"10.1091/mbc.E25-02-0050","url":null,"abstract":"Pericentromeric bottlebrush converts DNA into a stiff spring through density and organization of loops relative to the mitotic spindle axis. This spring is integral to tension-sensing mechanisms required for faithful chromosome segregation. Cohesin enrichment is a hallmark of yeast pericentric loops. We used haploid yeasts engineered to contain two instead of the normal 16 chromosomes to determine the number of centromeres required for cohesin loading to form a pericentric bottlebrush. In wild-type yeasts, the mitotic spindle is 1.5 µm long and 16 centromeres appear in tight clusters. Cohesin surrounds the metaphase spindle forming a cylindrical barrel and cross-linking the radial array of chromatin loops. In the two-chromosome strain, our findings show a disrupted cohesin barrel and a longer spindle (∼2.4 µm). The reduction in spring stiffness would lead to the increase in spindle length necessary to achieve a force balance with spindle microtubules. In the two-chromosome strain kinetochores are declustered. Additionally, coordination between the clusters moving toward the poles (anaphase A) and spindle elongation (anaphase B) is abrogated resulting in a mid-anaphase pause. The lack of anaphase A suggests that release and expansion of hitherto confined DNA loops contributes to synchronous chromosome segregation in anaphase.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"ar70"},"PeriodicalIF":3.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144029811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The PCM scaffold enables RNA localization to centrosomes. PCM支架使RNA定位到中心体。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-06-01 Epub Date: 2025-04-30 DOI: 10.1091/mbc.E25-03-0117

Junnan Fang, Weiyi Tian, Melissa A Quintanilla, Jordan R Beach, Dorothy A Lerit

{"title":"The PCM scaffold enables RNA localization to centrosomes.","authors":"Junnan Fang, Weiyi Tian, Melissa A Quintanilla, Jordan R Beach, Dorothy A Lerit","doi":"10.1091/mbc.E25-03-0117","DOIUrl":"10.1091/mbc.E25-03-0117","url":null,"abstract":"As microtubule-organizing centers, centrosomes direct assembly of the bipolar mitotic spindle required for chromosome segregation and genome stability. Centrosome activity requires the dynamic assembly of pericentriolar material (PCM), the composition and organization of which changes throughout the cell cycle. Recent studies highlight the conserved localization of several mRNAs encoded from centrosome-associated genes enriched at centrosomes, including Pericentrin-like protein (Plp) mRNA. However, relatively little is known about how RNAs localize to centrosomes and influence centrosome function. Here, we examine mechanisms underlying the subcellular localization of Plp mRNA. We find that Plp mRNA localization is puromycin-sensitive, and the Plp-coding sequence (CDS) is both necessary and sufficient for RNA localization, consistent with a cotranslational transport mechanism. We identify regions within the Plp CDS that regulate Plp mRNA localization. Finally, we show that protein-protein interactions critical for elaboration of the PCM scaffold permit RNA localization to centrosomes. Taken together, these findings inform the mechanistic basis of Plp mRNA localization and lend insight into the oscillatory enrichment of RNA at centrosomes.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"ar75"},"PeriodicalIF":3.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144018560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimized expansion microscopy reveals species-specific spindle microtubule organization in Xenopus egg extracts. 优化的扩展显微镜揭示了非洲爪蟾卵提取物中特定物种的纺锤体微管组织。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-06-01 Epub Date: 2025-05-06 DOI: 10.1091/mbc.E24-09-0421

Gabriel Guilloux, Maiko Kitaoka, Karel Mocaer, Claire Heichette, Laurence Duchesne, Rebecca Heald, Thierry Pecot, Romain Gibeaux

{"title":"Optimized expansion microscopy reveals species-specific spindle microtubule organization in Xenopus egg extracts.","authors":"Gabriel Guilloux, Maiko Kitaoka, Karel Mocaer, Claire Heichette, Laurence Duchesne, Rebecca Heald, Thierry Pecot, Romain Gibeaux","doi":"10.1091/mbc.E24-09-0421","DOIUrl":"10.1091/mbc.E24-09-0421","url":null,"abstract":"The spindle is key to cell division, ensuring accurate chromosome segregation. Although its assembly and function are well studied, the mechanisms regulating spindle architecture remain elusive. Here, we investigate spindle organization differences between Xenopus laevis and tropicalis, leveraging expansion microscopy (ExM) to overcome conventional imaging limitations. We optimized an ExM protocol tailored for Xenopus egg extract spindles, refining fixation, denaturation, and gelation to achieve higher resolution while preserving spindle integrity. Our protocol enables preexpansion immunofluorescence and is seamlessly compatible with both species. To quantitatively compare microtubule organization in expanded spindles between the two species, we developed an analysis pipeline that is able to characterize microtubule bundles throughout spindles. We show that X. laevis spindles exhibit overall a broader range of bundle sizes, while X. tropicalis spindles contain mostly smaller bundles. Although both species show larger bundles near the spindle center, X. tropicalis spindles otherwise consist of very small bundles, whereas X. laevis spindles contain more medium-sized bundles. Altogether, our work reveals species-specific spindle architectures and suggests their adaptation to the different spindle size and chromatin amount. By enhancing resolution and minimizing artifacts, our ExM approach provides new insights into spindle morphology and a robust tool for further studying these large cellular assemblies.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"ar73"},"PeriodicalIF":3.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144033911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A morphology and secretome map of pyroptosis. 焦亡的形态学和分泌组图。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-06-01 Epub Date: 2025-04-09 DOI: 10.1091/mbc.E25-03-0119

Michael J Lippincott, Jenna Tomkinson, Dave Bunten, Milad Mohammadi, Johanna Kastl, Johannes Knop, Ralf Schwandner, Jiamin Huang, Grant Ongo, Nathaniel Robichaud, Milad Dagher, Andrés Mansilla-Soto, Cynthia Saravia-Estrada, Masafumi Tsuboi, Carla Basualto-Alarcón, Gregory P Way

{"title":"A morphology and secretome map of pyroptosis.","authors":"Michael J Lippincott, Jenna Tomkinson, Dave Bunten, Milad Mohammadi, Johanna Kastl, Johannes Knop, Ralf Schwandner, Jiamin Huang, Grant Ongo, Nathaniel Robichaud, Milad Dagher, Andrés Mansilla-Soto, Cynthia Saravia-Estrada, Masafumi Tsuboi, Carla Basualto-Alarcón, Gregory P Way","doi":"10.1091/mbc.E25-03-0119","DOIUrl":"10.1091/mbc.E25-03-0119","url":null,"abstract":"Pyroptosis represents one type of programmed cell death. It is a form of inflammatory cell death that is canonically defined by caspase-1 cleavage and Gasdermin-mediated membrane pore formation. Caspase-1 initiates the inflammatory response (through IL-1β processing), and the N-terminal cleaved fragment of Gasdermin D polymerizes at the cell periphery forming pores to secrete proinflammatory markers. Cell morphology also changes in pyroptosis, with nuclear condensation and membrane rupture. However, recent research challenges canon, revealing a more complex secretome and morphological response in pyroptosis, including overlapping molecular characterization with other forms of cell death, such as apoptosis. Here, we take a multimodal, systems biology approach to characterize pyroptosis. We treated human peripheral blood mononuclear cells (PBMCs) with 36 different combinations of stimuli to induce pyroptosis or apoptosis. We applied both secretome profiling (nELISA) and high-content fluorescence microscopy (Cell Painting). To differentiate apoptotic, pyroptotic, and control cells, we used canonical secretome markers and modified our Cell Painting assay to mark the N-terminus of Gasdermin D. We trained hundreds of machine learning (ML) models to reveal intricate morphology signatures of pyroptosis that implicate changes across many different organelles and predict levels of many proinflammatory markers. Overall, our analysis provides a detailed map of pyroptosis which includes overlapping and distinct connections with apoptosis revealed through a mechanistic link between cell morphology and cell secretome.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":"36 6","pages":"ar63"},"PeriodicalIF":3.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144027285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Deletion of the plexin-D1 ectodomain leads to anoikis by suppressing integrin inside-out signaling. 丛状蛋白d1外畴的缺失通过抑制整合素内向外信号传导而导致anoikis。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-06-01 Epub Date: 2025-04-23 DOI: 10.1091/mbc.E25-02-0075

Toshihiko Toyofuku, Takako Ishikawa, Atsushi Kumanogoh

{"title":"Deletion of the plexin-D1 ectodomain leads to anoikis by suppressing integrin inside-out signaling.","authors":"Toshihiko Toyofuku, Takako Ishikawa, Atsushi Kumanogoh","doi":"10.1091/mbc.E25-02-0075","DOIUrl":"10.1091/mbc.E25-02-0075","url":null,"abstract":"Plexin-D1, mainly expressed in endothelial and cancer cells, regulates diverse effects, suppresses endothelial cell growth, and induces cancer cell migration and proliferation. Here, we demonstrated that plexin-D1 was cleaved by proteinase on cancer cells. To examine the role of cleaved plexin-D1 in cells, Madin-Darby canine kidney (MDCK) cells overexpressing truncated plexin-D1 were cultured in Matrigel. MDCK cells expressing plexin-D1 lacking the ectodomain (plexin-D1 ΔEC) underwent apoptosis. An adhesion assay for extracellular matrix (ECM) molecules showed that plexin-D1 ΔEC-expressing MDCK cells lost their affinity for the ECM. These results suggest that plexin-D1 ΔEC blocks integrin inside-out signaling, leading to detachment from the ECM and apoptosis, so-called anoikis. By contrast, MDCK cells expressing full-length plexin-D1 or plexin-D1 lacking the cytoplasmic domain (plexin-D1 ΔIC) developed multicellular branching tubular structures in Matrigel. This morphological change was blocked in plexin-D1-expressing MDCK cells by the hepatocyte growth factor receptor (Met) loss of function or by Met inhibitors. These results suggest that plexin-D1 associates with Met through the plexin-D1 extracellular domain, and this activates Met cytoplasmic kinase activity. We therefore conclude that plexin-D1 contains distinct domains that determine the fate of cancer cells.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":"36 6","pages":"ar71"},"PeriodicalIF":3.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144018311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Tetraspanin CD82 regulates Transforming Growth Factor β signaling in Hematopoietic Stem and Progenitor Cells. Tetraspanin CD82在造血干细胞和祖细胞中调控转化生长因子β信号。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-05-28 DOI: 10.1091/mbc.E24-10-0474

Erica Pascetti, Muskan Floren, Tatiane da Silva Fernandes, Carina Anastasio, Levi Doyle, Jennifer Gillette

{"title":"Tetraspanin CD82 regulates Transforming Growth Factor β signaling in Hematopoietic Stem and Progenitor Cells.","authors":"Erica Pascetti, Muskan Floren, Tatiane da Silva Fernandes, Carina Anastasio, Levi Doyle, Jennifer Gillette","doi":"10.1091/mbc.E24-10-0474","DOIUrl":"https://doi.org/10.1091/mbc.E24-10-0474","url":null,"abstract":"The cellular demand of the hematopoietic system is maintained by a rare pool of tissue-specific, hematopoietic stem cells (HSCs). HSCs are primarily maintained in a quiescent state but can be activated to exit quiescence and undergo self-renewal and differentiation in response to stress. The cytokine Transforming Growth Factor-β (TGF-β) plays an essential role in supporting HSC quiescence and activation, as one of the most potent inhibitors of HSPC growth. Therefore, how TGF-β signaling can be regulated in the context of HSCs is of significant interest as it may uncover novel mechanisms to target HSC activity. Previous studies revealed that the tetraspanin CD82 modulates the long-term HSC population, with CD82 knockout (KO) mice displaying increased HSC activation. Here, in this study, we connect the CD82 scaffold with the regulation of TGF-β signaling in hematopoietic stem and progenitor cells (HSPCs). We show that CD82KO leads to decreased TGF-β signaling, whereas increased CD82 expression promotes TGF-β activation. These changes in CD82-mediated TGF-β signaling are associated with extracellular matrix interactions, as fibronectin engagement is critical for promoting TGF-β signaling. Mechanistically, we find that CD82 stimulates enhanced TGF-β activation by promoting receptor crosstalk between TGF-β receptor I and integrin β1, resulting in downstream changes in cell proliferation. Collectively, these findings demonstrate that CD82 modulates canonical TGF-β signaling through receptor crosstalk mechanisms that may be targeted to alter the balance between HSC quiescence and activation.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"mbcE24100474"},"PeriodicalIF":3.1,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144173992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Midbody and Midbody Remnant: from cellular debris to signaling organelle with diagnostic and therapeutic potential. 中体和中体残体：从细胞碎片到具有诊断和治疗潜力的信号细胞器。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-05-28 DOI: 10.1091/mbc.E25-03-0120

Ryoko Kuriyama, J Michael Mullins, Ahna R Skop

引用次数: 0

Force-insensitive myosin-I enhances endocytosis robustness through actin network-scale collective ratcheting. 力不敏感肌球蛋白- 1通过肌动蛋白网络规模集体棘轮增强内吞稳健性。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-05-28 DOI: 10.1091/mbc.E25-03-0147

Michael A Ferrin, Ross T A Pedersen, David G Drubin, Matthew Akamatsu

{"title":"Force-insensitive myosin-I enhances endocytosis robustness through actin network-scale collective ratcheting.","authors":"Michael A Ferrin, Ross T A Pedersen, David G Drubin, Matthew Akamatsu","doi":"10.1091/mbc.E25-03-0147","DOIUrl":"https://doi.org/10.1091/mbc.E25-03-0147","url":null,"abstract":"Force production by Type-I myosins influences endocytic progression in many cell types. Since different myosin-I isoforms exhibit distinct force-dependent kinetic properties, it is important to investigate how these properties affect endocytic outcomes, and the mechanisms through which myosin-I contributes to endocytosis. To this end, we adapted our agent-based simulations of endocytic actin networks and incorporated nonprocessive, single-headed myosin motors at the base of the endocytic pit. We varied the unbinding rate and the force dependence of myosin unbinding. Our results revealed that the inclusion of myosin motors facilitated endocytic internalization, but only under kinetic regimes with rapid and less force-sensitive unbinding. Conversely, slow or strongly force-dependent unbinding impeded endocytic progression. As membrane tension increased, the boundary between assistive and inhibitory phases shifted, allowing the myosins to assist over larger regions of the kinetic landscape. Myosin-I's contribution to internalization could not be explained by direct force transduction or increased actin assembly. Instead, the myosins collectively bolstered the robustness of internalization by limiting pit retraction.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"mbcE25030147"},"PeriodicalIF":3.1,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144173968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Amino acid-level differences in alpha tubulin sequences are uniquely required for meiosis. α微管蛋白序列的氨基酸水平差异是减数分裂所必需的。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-05-28 DOI: 10.1091/mbc.E24-11-0529

Li Chen, Xi Chen, Anna Kashina

{"title":"Amino acid-level differences in alpha tubulin sequences are uniquely required for meiosis.","authors":"Li Chen, Xi Chen, Anna Kashina","doi":"10.1091/mbc.E24-11-0529","DOIUrl":"https://doi.org/10.1091/mbc.E24-11-0529","url":null,"abstract":"Members of the tubulin gene family members are essential components of the cytoskeleton, however functional diversity of tubulin isoforms is poorly understood. Here we addressed this question using Schizosaccharomyces pombe as a model system. These yeast encode two α- tubulins, nda2 and atb2, that are very similar at the amino acid level but differ in their roles in organism's survival: nda2 deletion is lethal, while lack of atb2 does not interfere with cell viability. Using CRISPR-Cas9 gene editing, we generated a yeast strain expressing atb2 amino acid sequence utilizing nda2 codon usage in the native nda2 locus. Such nda2-coded atb2 (NCA) yeast, unlike nda2 knockout, were viable and displayed no visible abnormalities in vegetative life cycle. Instead, they displayed strong impairments in sporulation and meiosis, linked to altered balance of several spindle proteins. Our data indicate that nda2 protein is uniquely required for normal meiosis, and identify novel protein- and nucleotide-level determinants driving functional distinction between closely related tubulin isoforms.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"mbcE24110529"},"PeriodicalIF":3.1,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144173926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Michael Patrick Sheetz, 1946-2025, a devotee of and major contributor to membrane and cytoskeletal biology. Michael Patrick Sheetz, 1946-2025，膜和细胞骨架生物学的爱好者和主要贡献者。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-05-28 DOI: 10.1091/mbc.E25-05-0208

Linda Kenney, Ron Vale, Jim Spudich

引用次数: 0