Nikita Sergejevs, Dönem Avci, Michael L van de Weijer, Robin A Corey, Marius K Lemberg, Pedro Carvalho
{"title":"Topology surveillance of the lanosterol demethylase CYP51A1 by Signal Peptide Peptidase.","authors":"Nikita Sergejevs, Dönem Avci, Michael L van de Weijer, Robin A Corey, Marius K Lemberg, Pedro Carvalho","doi":"10.1242/jcs.262333","DOIUrl":"https://doi.org/10.1242/jcs.262333","url":null,"abstract":"<p><p>Cleavage of transmembrane segments on target proteins by the aspartyl intramembrane protease signal peptide peptidase (SPP) has been linked to immunity, viral infection and protein quality control. How SPP recognizes its various substrates and specifies their fate remains elusive. Here we identified the lanosterol demethylase CYP51A1 as an SPP substrate and show that SPP-catalyzed cleavage triggers CYP51A1 clearance by ER-associated degradation (ERAD). We observe that SPP targets only a fraction of CYP51A1 molecules and identified an amphipathic helix in the N-terminus as a key determinant for SPP recognition. SPP recognition is remarkably specific to CYP51A1 molecules with the amphipathic helix aberrantly inserted in the membrane with a type II orientation. Thus, our data are consistent with a role for SPP in topology surveillance, triggering the clearance of certain, potentially non-functional conformers.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142604271","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}
{"title":"Shear stress-stimulated AMPK couples endothelial cell mechanics, metabolism, and vasodilation.","authors":"Nicholas M Cronin, Logan W Dawson, Kris A DeMali","doi":"10.1242/jcs.262232","DOIUrl":"https://doi.org/10.1242/jcs.262232","url":null,"abstract":"<p><p>Endothelial cells respond to mechanical force by stimulating cellular signaling, but how these pathways are linked to elevations in cell metabolism and whether metabolism supports the mechanical response remains poorly understood. Here, we show that the application of force to endothelial cells stimulates VE-cadherin to activate liver kinase B1 (LKB1) and AMP-activated protein kinase (AMPK), a master regulator of energy homeostasis. VE-cadherin stimulated AMPK increases eNOS activity and localization to the plasma membrane, reinforcement of the actin cytoskeleton and cadherin adhesion complex, and glucose uptake. We present evidence for the increase in metabolism being necessary to fortify the adhesion complex, actin cytoskeleton, and cellular alignment. Together these data extend the paradigm for how mechanotransduction and metabolism are linked to include a connection to vasodilation, thereby providing new insight into how diseases involving contractile, metabolic, and vasodilatory disturbances arise.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142604105","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}
Samantha Bunner, Kelsey Prince, Emily M Pujadas Liwag, Nebiyat Eskndir, Karan Srikrishna, Antonia Amonu McCarthy, Anna Kuklinski, Olivia Jackson, Pedro Pellegrino, Shrushti Jagtap, Imuetiyan Eweka, Colman Lawlor, Emma Eastin, Griffin Yas, Julianna Aiello, Nathan LaPointe, Isabelle Schramm von Blucher, Jillian Hardy, Jason Chen, Schuyler Figueroa, Vadim Backman, Anne Janssen, Mary Packard, Katherine Dorfman, Luay Almassalha, Michael Seifu Bahiru, Andrew D Stephens
{"title":"Decreased DNA density is a better indicator of a nuclear bleb than lamin B loss.","authors":"Samantha Bunner, Kelsey Prince, Emily M Pujadas Liwag, Nebiyat Eskndir, Karan Srikrishna, Antonia Amonu McCarthy, Anna Kuklinski, Olivia Jackson, Pedro Pellegrino, Shrushti Jagtap, Imuetiyan Eweka, Colman Lawlor, Emma Eastin, Griffin Yas, Julianna Aiello, Nathan LaPointe, Isabelle Schramm von Blucher, Jillian Hardy, Jason Chen, Schuyler Figueroa, Vadim Backman, Anne Janssen, Mary Packard, Katherine Dorfman, Luay Almassalha, Michael Seifu Bahiru, Andrew D Stephens","doi":"10.1242/jcs.262082","DOIUrl":"10.1242/jcs.262082","url":null,"abstract":"<p><p>Nuclear blebs are herniations of the nucleus that occur in diseased nuclei that cause nuclear rupture leading to cellular dysfunction. Chromatin and lamins are two of the major structural components of the nucleus that maintain its shape and function, but their relative roles in nuclear blebbing remain elusive. To determine the composition of nuclear blebs, we compared the immunofluorescence intensity of DNA and lamin B in the main nucleus body to the nuclear bleb across cell types and perturbations. DNA density in the nuclear bleb was consistently decreased to about half of the nuclear body while lamin B levels in the nuclear bleb varied widely. Partial Wave Spectroscopic (PWS) microscopy recapitulated significantly decreased likelihood of high-density domains in the nuclear bleb versus body, independent of lamin B. Time lapse imaging into immunofluorescence reveals that decreased DNA density marks all nuclear blebs while decreased lamin B1 levels only occur in blebs that have recently ruptured. Thus, decreased DNA density is a better marker of a nuclear bleb than lamin B level.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142583444","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}
David Cohen, Dawn Fernandez, Francisco Lázaro-Diéguez, Beatrix Überheide, Anne Müsch
{"title":"Borg5/Cdc42EP1 restricts contractility and motility in epithelial MDCK cells.","authors":"David Cohen, Dawn Fernandez, Francisco Lázaro-Diéguez, Beatrix Überheide, Anne Müsch","doi":"10.1242/jcs.261705","DOIUrl":"https://doi.org/10.1242/jcs.261705","url":null,"abstract":"<p><p>The Borg/Cdc42EP family comprises septin binding proteins, which are known to promote septin-dependent stress fibers and acto-myosin contractility. We show here that epithelial Borg5/Cdc42ep1 instead limits contractility, cell-cell adhesion tension and motility as is required for the acquisition of columnar, isotropic cell morphology in mature MDCK monolayers. Borg5 depletion inhibited the development of the lateral F-actin cortex, stimulated microtubule-dependent leading-edge lamellae as well as radial stress fibers and, independently of the basal F-actin phenotype, caused anisotropy of apical surfaces within compacted monolayers. We determined that Borg5 limits septin-colocalization with microtubules, and that like Septin 2, Borg5 interacts with the rod-domain of Myosin- IIA. The interaction of Myosin-IIA with Borg5 was reduced in the presence of septins. Because septins also mediate myosin activation, we propose that Borg5 limits contractility in MDCK cells in part by counteracting septin-associated myosin activity.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142583432","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}
Kyung-Won Min, Kyoung-Min Choi, Hyejin Mun, Seungbeom Ko, Ji Won Lee, Cari A Sagum, Mark T Bedford, Young-Kook Kim, Joe R Delaney, Jung-Hyun Cho, Ted M Dawson, Valina L Dawson, Waleed Twal, Dong-Chan Kim, Clarisse H Panganiban, Hainan Lang, Xin Zhou, Seula Shin, Jian Hu, Tilman Heise, Sang-Ho Kwon, Dongsan Kim, Young Hwa Kim, Sung-Ung Kang, Kyungmin Kim, Sydney Lewis, Ahmet Eroglu, Seonghyun Ryu, Dongin Kim, Jeong Ho Chang, Junyang Jung, Je-Hyun Yoon
{"title":"Mature microRNA-binding protein QKI suppresses extracellular microRNA let-7b release.","authors":"Kyung-Won Min, Kyoung-Min Choi, Hyejin Mun, Seungbeom Ko, Ji Won Lee, Cari A Sagum, Mark T Bedford, Young-Kook Kim, Joe R Delaney, Jung-Hyun Cho, Ted M Dawson, Valina L Dawson, Waleed Twal, Dong-Chan Kim, Clarisse H Panganiban, Hainan Lang, Xin Zhou, Seula Shin, Jian Hu, Tilman Heise, Sang-Ho Kwon, Dongsan Kim, Young Hwa Kim, Sung-Ung Kang, Kyungmin Kim, Sydney Lewis, Ahmet Eroglu, Seonghyun Ryu, Dongin Kim, Jeong Ho Chang, Junyang Jung, Je-Hyun Yoon","doi":"10.1242/jcs.261575","DOIUrl":"10.1242/jcs.261575","url":null,"abstract":"<p><p>Argonaute (AGO), a component of RNA-induced silencing complexes (RISCs), is a representative RNA-binding protein (RBP) known to bind with mature microRNAs (miRNAs) and is directly involved in post-transcriptional gene silencing. However, despite the biological significance of miRNAs, the roles of other miRNA-binding proteins (miRBPs) remain unclear in the regulation of miRNA loading, dissociation from RISCs and extracellular release. In this study, we performed protein arrays to profile miRBPs and identify 118 RBPs that directly bind to miRNAs. Among those proteins, the RBP quaking (QKI) inhibits extracellular release of the mature microRNA let-7b by controlling the loading of let-7b into extracellular vesicles via additional miRBPs such as AUF1 (also known as hnRNPD) and hnRNPK. The enhanced extracellular release of let-7b after QKI depletion activates Toll-like receptor 7 (TLR7) and promotes the production of proinflammatory cytokines in recipient cells, leading to brain inflammation in the mouse cortex. Thus, this study reveals the contribution of QKI to the inhibition of brain inflammation via regulation of extracellular let-7b release.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142288103","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}
{"title":"Bi-directional regulation between inflammation and stem cells in the respiratory tract.","authors":"Jinwook Choi, Jakub Chudziak, Joo-Hyeon Lee","doi":"10.1242/jcs.263413","DOIUrl":"https://doi.org/10.1242/jcs.263413","url":null,"abstract":"<p><p>Inflammation plays a crucial role in tissue injury, repair and disease, orchestrating a complex interplay of immune responses and cellular processes. Recent studies have uncovered the intricate connection between inflammation and stem cell dynamics, shedding light on the central role of stem cells in tissue regeneration. This Review highlights the significance of inflammation in shaping epithelial stem cell dynamics and its implications for tissue repair, regeneration and aging. We explore the multifaceted interactions between inflammation and stem cells, focusing on how inflammatory signals affect stem cell behavior and fate as well as the remodeling of their niche in the respiratory tract. We also discuss the concept of 'inflammatory memory' in epithelial stem cells, where prior inflammatory stimuli endow these cells with enhanced regenerative potential and confer long-lasting protective mechanisms for maintaining tissue integrity and function. Furthermore, we review the impact of cell senescence induced by inflammation on tissue regeneration and aging, delving into the molecular mechanisms underlying the modulation of signaling pathways, epigenetic modifications and cellular crosstalk. Understanding these dynamic processes not only deepens our knowledge of tissue homeostasis and repair but also holds profound implications for regenerative medicine strategies aimed at preventing pulmonary diseases.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142604274","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}
Robert T Johnson, Finn Wostear, Reesha Solanki, Oliver Steward, Alice Bradford, Christopher Morris, Stefan Bidula, Derek T Warren
{"title":"A microtubule stability switch alters isolated vascular smooth muscle Ca2+ flux in response to matrix rigidity.","authors":"Robert T Johnson, Finn Wostear, Reesha Solanki, Oliver Steward, Alice Bradford, Christopher Morris, Stefan Bidula, Derek T Warren","doi":"10.1242/jcs.262310","DOIUrl":"10.1242/jcs.262310","url":null,"abstract":"<p><p>During ageing, the extracellular matrix of the aortic wall becomes more rigid. In response, vascular smooth muscle cells (VSMCs) generate enhanced contractile forces. Our previous findings demonstrate that VSMC volume is enhanced in response to increased matrix rigidity, but our understanding of the mechanisms regulating this process remain incomplete. In this study, we show that microtubule stability in VSMCs is reduced in response to enhanced matrix rigidity via Piezo1-mediated Ca2+ influx. Moreover, VSMC volume and Ca2+ flux is regulated by microtubule dynamics; microtubule-stabilising agents reduced both VSMC volume and Ca2+ flux on rigid hydrogels, whereas microtubule-destabilising agents increased VSMC volume and Ca2+ flux on pliable hydrogels. Finally, we show that disruption of the microtubule deacetylase HDAC6 uncoupled these processes and increased α-tubulin acetylation on K40, VSMC volume and Ca2+ flux on pliable hydrogels, but did not alter VSMC microtubule stability. These findings uncover a microtubule stability switch that controls VSMC volume by regulating Ca2+ flux. Taken together, these data demonstrate that manipulation of microtubule stability can modify VSMC response to matrix stiffness.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142288099","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}
Adeline Colussi, Leonardo Almeida-Souza, Harvey T McMahon
{"title":"A single-particle analysis method for detecting membrane remodelling and curvature sensing.","authors":"Adeline Colussi, Leonardo Almeida-Souza, Harvey T McMahon","doi":"10.1242/jcs.263533","DOIUrl":"10.1242/jcs.263533","url":null,"abstract":"<p><p>In biology, shape and function are related. Therefore, it is important to understand how membrane shape is generated, stabilised and sensed by proteins and how this relates to organelle function. Here, we present an assay that can detect curvature preference and membrane remodelling with free-floating liposomes using protein concentrations in physiologically relevant ranges. The assay reproduced known curvature preferences of BAR domains and allowed the discovery of high-curvature preference for the PH domain of AKT and the FYVE domain of HRS (also known as HGS). In addition, our method reproduced the membrane vesiculation activity of the ENTH domain of epsin-1 (EPN1) and showed similar activity for the ANTH domains of PiCALM and Hip1R. Finally, we found that the curvature sensitivity of the N-BAR domain of endophilin inversely correlates to membrane charge and that deletion of its N-terminal amphipathic helix increased its curvature specificity. Thus, our method is a generally applicable qualitative method for assessing membrane curvature sensing and remodelling by proteins.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142347441","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}
Brittany J Carr, Dominic Skitsko, Linnea M Kriese, Jun Song, Zixuan Li, Myeong Jin Ju, Orson L Moritz
{"title":"prominin-1-null Xenopus laevis develop subretinal drusenoid-like deposits, cone-rod dystrophy and RPE atrophy.","authors":"Brittany J Carr, Dominic Skitsko, Linnea M Kriese, Jun Song, Zixuan Li, Myeong Jin Ju, Orson L Moritz","doi":"10.1242/jcs.262298","DOIUrl":"10.1242/jcs.262298","url":null,"abstract":"<p><p>Prominin-1 (PROM1) variants are associated with inherited, non-syndromic vision loss. We used CRISPR/Cas9 to induce prom1-null mutations in Xenopus laevis and then tracked retinal disease progression from the ages of 6 weeks to 3 years. We found that prom1-null-associated retinal degeneration in frogs was age-dependent and involved retinal pigment epithelium (RPE) dysfunction preceding photoreceptor degeneration. Before photoreceptor degeneration occurred, aging prom1-null frogs developed larger and increasing numbers of cellular debris deposits in the subretinal space and outer segment layer, which resembled subretinal drusenoid deposits (SDDs) in their location, histology and representation as seen by color fundus photography and optical coherence tomography (OCT). Evidence for an RPE origin of these deposits included infiltration of pigment granules into the deposits, thinning of the RPE as measured by OCT, and RPE disorganization as measured by histology and OCT. The appearance and accumulation of SDD-like deposits and RPE thinning and disorganization in our animal model suggests an underlying disease mechanism for prom1-null-mediated blindness that involves death and dysfunction of the RPE preceding photoreceptor degeneration, instead of direct effects upon photoreceptor outer segment morphogenesis, as was previously hypothesized.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142361605","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}
{"title":"An improved tetracycline-inducible expression system for fission yeast.","authors":"Xiao-Hui Lyu, Yu-Sheng Yang, Zhao-Qian Pan, Shao-Kai Ning, Fang Suo, Li-Lin Du","doi":"10.1242/jcs.263404","DOIUrl":"10.1242/jcs.263404","url":null,"abstract":"<p><p>The ability to manipulate gene expression is valuable for elucidating gene function. In the fission yeast Schizosaccharomyces pombe, the most widely used regulatable expression system is the nmt1 promoter and its two attenuated variants. However, these promoters have limitations, including a long lag, incompatibility with rich media and unsuitability for non-dividing cells. Here, we present a tetracycline-inducible system free of these shortcomings. Our system features the enotetS promoter, which achieves a similar induced level and a higher induction ratio compared to the nmt1 promoter, without exhibiting a lag. Additionally, our system includes four weakened enotetS variants, offering an expression range similar to that of the nmt1 series promoters but with more intermediate levels. To enhance usability, each promoter is combined with a Tet-repressor-expressing cassette in an integration plasmid. Importantly, our system can be used in non-dividing cells, enabling the development of a synchronous meiosis induction method with high spore viability. Moreover, our system allows for the shutdown of gene expression and the generation of conditional loss-of-function mutants. This system provides a versatile and powerful tool for manipulating gene expression in fission yeast.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142347442","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}