Molecular Biology of the Cell最新文献_第2页

Behind the scenes of cellular organization: Quantifying spatial phenotypes of puncta structures with statistical models including random fields. 细胞组织的幕后：用包括随机场在内的统计模型定量点状结构的空间表型。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-01-09 DOI: 10.1091/mbc.E24-10-0461

Kyriacos Nicolaou, Josiah B Passmore, Lukas C Kapitein, Bela M Mulder, Florian Berger

{"title":"Behind the scenes of cellular organization: Quantifying spatial phenotypes of puncta structures with statistical models including random fields.","authors":"Kyriacos Nicolaou, Josiah B Passmore, Lukas C Kapitein, Bela M Mulder, Florian Berger","doi":"10.1091/mbc.E24-10-0461","DOIUrl":"https://doi.org/10.1091/mbc.E24-10-0461","url":null,"abstract":"The cellular interior is a spatially complex environment shaped by non-trivial stochastic and biophysical processes. Within this complexity, spatial organizational principles-also called spatial phenotypes-often emerge with functional implications. However, identifying and quantifying these phenotypes in the stochastic intracellular environment is challenging. To overcome this challenge for puncta, we discuss the use of inference of point-process models that link the density of points to other imaged structures and a random field that captures hidden processes. We apply these methods to simulated data and multiplexed immunofluorescence images of Vero E6 cells. Our analysis suggests that peroxisomes are likely to be found near the perinuclear region, overlapping with the ER, and located within a distance of 1 μm to mitochondria. Moreover, the random field captures a hidden variation of the mean density in the order of 15 μm. This length scale could provide critical information for further developing mechanistic hypotheses and models. By using spatial statistical models including random fields, we add a valuable perspective to cell biology.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"mbcE24100461"},"PeriodicalIF":3.1,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142951748","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

Large, recursive membrane platforms are associated to Trop-1, Trop-2 and protein kinase signaling for cell growth. 大的、递归的膜平台与细胞生长的Trop-1、Trop-2和蛋白激酶信号有关。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-01-09 DOI: 10.1091/mbc.E24-06-0267

Marco Trerotola, Valeria Relli, Romina Tripaldi, Pasquale Simeone, Emanuela Guerra, Andrea Sacchetti, Martina Ceci, Ludovica Pantalone, Paolo Ciufici, Antonino Moschella, Valeria R Caiolfa, Moreno Zamai, Saverio Alberti

{"title":"Large, recursive membrane platforms are associated to Trop-1, Trop-2 and protein kinase signaling for cell growth.","authors":"Marco Trerotola, Valeria Relli, Romina Tripaldi, Pasquale Simeone, Emanuela Guerra, Andrea Sacchetti, Martina Ceci, Ludovica Pantalone, Paolo Ciufici, Antonino Moschella, Valeria R Caiolfa, Moreno Zamai, Saverio Alberti","doi":"10.1091/mbc.E24-06-0267","DOIUrl":"https://doi.org/10.1091/mbc.E24-06-0267","url":null,"abstract":"The transmembrane glycoproteins Trop-1/EpCAM and Trop-2 independently trigger Ca2+ and kinase signals for cell growth and tumor progression. Our findings indicated that Trop-1 and Trop-2 tightly colocalize at macroscopic, ruffle-like protrusions (RLP), that elevate from the cell perimeter, and locally recur over hundreds of seconds. These previously unrecognized elevated membrane regions ≥20 µm-long, up to 1.5 µm high were revealed by Z-stack analysis and three-dimensional reconstruction of signal transducer-hosting plasma membrane regions. Trop-2 stimulates cell growth through a membrane super-complex that comprises CD9, PKCα, ion pumps and cytoskeletal components. Our findings indicated that the growth-driving Trop-2 super-complex assembles at RLP. RLP behaved as sites of clustering of signal transducers, of phosphorylation/activation of growth-driving kinases, as recruitment sites of PKCα and as origin of Ca2+ signaling waves, suggesting RLP to be novel signaling platforms in living cells. RLP were induced by growth factors and disappeared upon growth factor deprivation and β-actin depolymerization, candidating RLP to be functional platforms for high-dimensional signaling for cell growth. [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text].","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"mbcE24060267"},"PeriodicalIF":3.1,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142951790","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

Cul3 substrate adaptor SPOP targets Nup153 for degradation. Cul3衬底适配器SPOP以Nup153为降解目标。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-01-09 DOI: 10.1091/mbc.E24-04-0198

Joseph Y Ong, Mai Abdusamad, Ivan Ramirez, Ankur Gholkar, Xiaoxuan Zhang, Thomas V Gimeno, Jorge Z Torres

{"title":"Cul3 substrate adaptor SPOP targets Nup153 for degradation.","authors":"Joseph Y Ong, Mai Abdusamad, Ivan Ramirez, Ankur Gholkar, Xiaoxuan Zhang, Thomas V Gimeno, Jorge Z Torres","doi":"10.1091/mbc.E24-04-0198","DOIUrl":"10.1091/mbc.E24-04-0198","url":null,"abstract":"SPOP is a Cul3 substrate adaptor responsible for the degradation of many proteins related to cell growth and proliferation. Because mutation or misregulation of SPOP drives cancer progression, understanding the suite of SPOP substrates is important to understanding the regulation of cell proliferation. Here, we identify Nup153, a component of the nuclear basket of the nuclear pore complex, as a novel substrate of SPOP. SPOP and Nup153 bind to each other and colocalize at the nuclear envelope and some nuclear foci in cells. The binding interaction between SPOP and Nup153 is complex and multivalent. Nup153 is ubiquitylated and degraded upon expression of SPOPWT but not its substrate binding-deficient mutant SPOPF102C. Depletion of SPOP via RNAi leads to Nup153 stabilization. Upon loss of SPOP activity, the nuclear envelope localization of spindle assembly checkpoint protein Mad1, which is tethered to the nuclear envelope by Nup153, is stronger. Altogether, our results demonstrate that SPOP regulates Nup153 levels and expands our understanding of the role of SPOP in protein and cellular homeostasis. [Media: see text] [Media: see text] [Media: see text].","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"mbcE24040198"},"PeriodicalIF":3.1,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142951789","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

Close cooperation between Semi1 and Semi2 proteins is essential for pronuclear positioning in Tetrahymena thermophila. 在嗜热四膜虫中，半1和半2蛋白之间的密切合作对原核定位至关重要。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-01-09 DOI: 10.1091/mbc.E24-11-0503

Takahiko Akematsu, Josef Loidl, Yasuhiro Fukuda, Masaaki Iwamoto

{"title":"Close cooperation between Semi1 and Semi2 proteins is essential for pronuclear positioning in Tetrahymena thermophila.","authors":"Takahiko Akematsu, Josef Loidl, Yasuhiro Fukuda, Masaaki Iwamoto","doi":"10.1091/mbc.E24-11-0503","DOIUrl":"https://doi.org/10.1091/mbc.E24-11-0503","url":null,"abstract":"During sexual reproduction in the ciliate Tetrahymena thermophila, meiosis occurs in the germline micronucleus, resulting in the formation of four haploid micronuclei. Of these, only one is selected to evade autophagy, and subsequently migrates to the membrane junction with the partner cell for reciprocal pronuclear exchange. We previously demonstrated that the transmembrane protein Semi1 is essential for this nuclear migration. Semi1 is specifically expressed in mating cells and localizes to the periphery of the selected nucleus. Loss of Semi1 disrupts nuclear attachment to the junction, leading to infertility. However, the mechanism by which Semi1 positions the nucleus at the junction remains unclear. Here, we report that the Semi1-interacting protein, Semi2, is also necessary for proper nuclear positioning. Deletion of Semi2 results in the same nuclear mislocalization phenotype and infertility observed in Semi1 mutant cells. Semi2 colocalizes with Semi1, but in the absence of Semi1, Semi2 fails to exhibit perinuclear localization. The selected nucleus anchors to microtubules prior to migration, a process dependent on both Semi1 and Semi2. We propose a model in which Semi1 recruits Semi2 to the selected nucleus, facilitating the interaction between the nucleus and microtubules required for proper nuclear positioning at the membrane junction.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"mbcE24110503"},"PeriodicalIF":3.1,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142951788","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

Valosin-containing protein p97 extracts capping protein CP110 from the mother centriole to promote ciliogenesis. 含有valosin的蛋白p97从母体中心粒中提取封顶蛋白CP110，促进纤毛发生。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-01-09 DOI: 10.1091/mbc.E24-10-0455

Rahit Dewanji, Naava Naslavsky, Steve Caplan

{"title":"Valosin-containing protein p97 extracts capping protein CP110 from the mother centriole to promote ciliogenesis.","authors":"Rahit Dewanji, Naava Naslavsky, Steve Caplan","doi":"10.1091/mbc.E24-10-0455","DOIUrl":"https://doi.org/10.1091/mbc.E24-10-0455","url":null,"abstract":"The primary cilium is a crucial signaling organelle that can be generated by most human cells, and impediments to primary ciliogenesis lead to a variety of developmental disorders known as ciliopathies. The removal of the capping protein, CP110, from the mother centriole is a crucial early step that promotes generation of the ciliary vesicle and ciliogenesis. Recent studies have demonstrated that CP110 undergoes polyubiquitination and degradation in the proteosome, but the mechanisms of unfolding and removal from the mother centriole remain unknown. Herein we demonstrate that p97/Valosin-containing protein (VCP or Cdc48), a member of the ATPase Associated with diverse Activities (AAA) protein family, is responsible for removal of CP110 from the mother centriole. We show that use of p97 knock-down or inhibition impairs ciliogenesis, in a mechanism dependent on CP110. Our findings demonstrate a novel role for p97 in the process of primary ciliogenesis, and support a mechanism by which ubiquitinated CP110 is degraded in a process that requires p97-mediated unfolding and removal from the mother centriole.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"mbcE24100455"},"PeriodicalIF":3.1,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142951791","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

Parkinson disease-associated toxic exposures selectively upregulate vesicular glutamate transporter vGlut2 in a model of human cortical neurons. 在人类皮质神经元模型中，帕金森病相关毒性暴露选择性上调水疱性谷氨酸转运蛋白vGlut2。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-01-02 DOI: 10.1091/mbc.E24-08-0376

Karis A Clark, Andrew J White, Wojciech Paslawski, Kellianne D Alexander, Shaoning Peng, Tracy L Young-Pearse, Per Svenningsson, Dennis J Selkoe, Gary P H Ho

{"title":"Parkinson disease-associated toxic exposures selectively upregulate vesicular glutamate transporter vGlut2 in a model of human cortical neurons.","authors":"Karis A Clark, Andrew J White, Wojciech Paslawski, Kellianne D Alexander, Shaoning Peng, Tracy L Young-Pearse, Per Svenningsson, Dennis J Selkoe, Gary P H Ho","doi":"10.1091/mbc.E24-08-0376","DOIUrl":"https://doi.org/10.1091/mbc.E24-08-0376","url":null,"abstract":"Parkinson disease (PD) is the second most common neurodegenerative disease, characterized by both motor and cognitive features. Motor symptoms primarily involve midbrain dopaminergic neurons, while cognitive dysfunction involves cortical neurons. Environmental factors are important contributors to PD risk. In rodents, rare midbrain dopaminergic neurons which co-express the vesicular glutamate transporter 2 (vGlut2) are resistant to various toxins which induce dopaminergic neurodegeneration. However, it is unclear how, and with what degree of specificity, cortical glutamatergic neurons respond to PD-associated exposures with respect to vGlut2. Here, we found that vGlut2 in stem cell derived human cortical-like glutamatergic neurons was upregulated in a highly specific manner to certain PD-related chemicals, such as rotenone, but not others, such as paraquat. Further, exposure to recombinant pre-formed fibrils (PFFs) of alpha-synuclein (αS), a protein which accumulates in PD, also increased vGlut2, while fibrils from non-PD related proteins did not. This effect did not involve templated aggregation of endogenous αS. Finally, knockdown of vGlut2 sensitized cortical neurons to rotenone, supporting a functional role in resilience. Thus, upregulation of vGlut2 occurs in a highly selective manner in response to specific PD-associated exposures in a model of cortical glutamatergic neurons, a key cell type for understanding PD dementia.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"mbcE24080376"},"PeriodicalIF":3.1,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142922089","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 large reverse-genetic screen identifies numerous regulators of testis nascent myotube collective cell migration and collective organ sculpting. 一个大的反向遗传筛选确定了睾丸新生肌管集体细胞迁移和集体器官雕刻的许多调节因子。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-01-02 DOI: 10.1091/mbc.E24-10-0456

Maik C Bischoff, Jenevieve E Norton, Erika A Munguia, Sarah E Clark, Noah J Gurley, Rebecca Korankye, Emmanuel Addai Gyabaah, Taino Encarnacion, Christopher J Serody, Corbin D Jones, Mark Peifer

{"title":"A large reverse-genetic screen identifies numerous regulators of testis nascent myotube collective cell migration and collective organ sculpting.","authors":"Maik C Bischoff, Jenevieve E Norton, Erika A Munguia, Sarah E Clark, Noah J Gurley, Rebecca Korankye, Emmanuel Addai Gyabaah, Taino Encarnacion, Christopher J Serody, Corbin D Jones, Mark Peifer","doi":"10.1091/mbc.E24-10-0456","DOIUrl":"10.1091/mbc.E24-10-0456","url":null,"abstract":"Collective cell migration is critical for morphogenesis, homeostasis, and wound healing. Migrating mesenchymal cells form tissues that shape the body's organs. We developed a powerful model, exploring how Drosophila nascent myotubes migrate onto the testis during pupal development, forming the muscles ensheathing it and creating its characteristic spiral shape. To define genes regulating this, we used RNAseq to identify genes expressed in myotubes during migration. Using this dataset, we curated a list of 131 ligands, receptors, and cytoskeletal regulators, including all Rho/Ras/Rap1 regulators, as candidates. We then expressed 279 shRNAs targeting these genes and examined adult testes. We identified 29 genes with diverse roles in morphogenesis. Some have phenotypes consistent with defective migration, while others alter testis shape in different ways, revealing the underlying logic of testis morphogenesis. We followed up the Rho-family GEF dPix in detail. dPix knockdown drastically reduced migration and thus muscle coverage. Our data suggest different isoforms of dPix play distinct roles in this process and reveal a role for its partner Git. We also explored whether dPix regulates Cdc42 activity or cell adhesion. Our RNAseq dataset and genetic analysis provide an important resource for the community to explore cell migration and organ morphogenesis.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"mbcE24100456"},"PeriodicalIF":3.1,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142922087","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

Movement of the endoplasmic reticulum is driven by multiple classes of vesicles marked by Rab-GTPases. 内质网的运动是由多类以Rab-GTPases为标志的囊泡驱动的。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-01-01 Epub Date: 2024-12-04 DOI: 10.1091/mbc.E24-04-0197

Allison Langley, Sarah Abeling-Wang, Erinn Wagner, John Salogiannis

{"title":"Movement of the endoplasmic reticulum is driven by multiple classes of vesicles marked by Rab-GTPases.","authors":"Allison Langley, Sarah Abeling-Wang, Erinn Wagner, John Salogiannis","doi":"10.1091/mbc.E24-04-0197","DOIUrl":"10.1091/mbc.E24-04-0197","url":null,"abstract":"Peripheral endoplasmic reticulum (ER) tubules move along microtubules to interact with various organelles through membrane contact sites. Traditionally, ER moves by either sliding along stable microtubules via molecular motors or attaching to the plus ends of dynamic microtubules through tip attachment complexes (TAC). A recently discovered third process, hitchhiking, involves motile vesicles pulling ER tubules along microtubules. Previous research showed that ER hitchhikes on Rab5- and Rab7-marked endosomes, but it is uncertain whether other Rab-vesicles can do the same. In U2OS cells, we screened Rabs for their ability to cotransport with ER tubules and found that ER hitchhikes on post-Golgi vesicles marked by Rab6 (isoforms a and b). Rab6-ER hitchhiking occurs independently of ER-endolysosome contacts and TAC-mediated ER movement. Depleting Rab6 and the motility of Rab6-vesicles reduces overall ER movement. Conversely, relocating these vesicles to the cell periphery causes peripheral ER accumulation, indicating that Rab6-vesicle motility is crucial for a subset of ER movements. Proximal post-Golgi vesicles marked by TGN46 are involved in Rab6-ER hitchhiking, while late Golgi vesicles (Rabs 8/10/11/13/14) are not essential for ER movement. Our further analysis finds that ER to Golgi vesicles marked by Rab1 are also capable of driving a subset of ER movements. Taken together, our findings suggest that ER hitchhiking on Rab-vesicles is a significant mode of ER movement.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"ar9"},"PeriodicalIF":3.1,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11742117/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142780523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A defined tubby domain β-barrel surface region of TULP3 mediates ciliary trafficking of diverse cargoes. TULP3的一个确定的管状结构域β-管表面区域介导了多种货物的纤毛运输。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-01-01 Epub Date: 2024-11-20 DOI: 10.1091/mbc.E24-09-0426

Vivek Reddy Palicharla, Hemant B Badgandi, Sun-Hee Hwang, Emilie Legué, Karel F Liem, Saikat Mukhopadhyay

{"title":"A defined tubby domain β-barrel surface region of TULP3 mediates ciliary trafficking of diverse cargoes.","authors":"Vivek Reddy Palicharla, Hemant B Badgandi, Sun-Hee Hwang, Emilie Legué, Karel F Liem, Saikat Mukhopadhyay","doi":"10.1091/mbc.E24-09-0426","DOIUrl":"10.1091/mbc.E24-09-0426","url":null,"abstract":"The primary cilium is a paradigmatic subcellular compartment at the nexus of numerous cellular and morphogenetic pathways. The tubby family protein TULP3 acts as an adapter of the intraflagellar transport complex A in transporting integral membrane and membrane-associated lipidated proteins into cilia. However, the mechanisms by which TULP3 coordinates ciliary transport of diverse cargoes is not well understood. Here, we provide molecular insights into TULP3-mediated ciliary cargo recognition. We screened for critical TULP3 residues by proximity biotinylation-mass spectrometry, structural analysis, and testing TULP3 variants in human patients with hepatorenal fibrocystic disease and spina bifida. The TULP3 residues we identified 1) were located on one side of the β-barrel of the tubby domain away from the phosphoinositide binding site, 2) mediated ciliary trafficking of lipidated and transmembrane cargoes, and 3) determined proximity with these cargoes in vivo without affecting ciliary localization, phosphoinositide binding or hydrodynamic properties of TULP3. Overall, these findings implicate a specific region of one of the surfaces of the TULP3 β-barrel in ciliary trafficking of diverse cargoes. This region overlooks the β-strands 8-12 of the β-barrel and is away from the membrane anchoring phosphoinositide binding site. Targeting the TULP3-cargo interactions could provide therapeutics in ciliary trafficking diseases.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"ar1"},"PeriodicalIF":3.1,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11742108/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142681900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dominant negative mutations in yeast Hsp90 indicate triage decision mechanism targeting client proteins for degradation. 酵母 Hsp90 的显性负突变表明了针对客户蛋白降解的分流决策机制。

IF 3.1 3区生物学

Molecular Biology of the Cell Pub Date : 2025-01-01 Epub Date: 2024-11-20 DOI: 10.1091/mbc.E24-07-0309

Julia M Flynn, Margot E Joyce, Daniel N A Bolon

{"title":"Dominant negative mutations in yeast Hsp90 indicate triage decision mechanism targeting client proteins for degradation.","authors":"Julia M Flynn, Margot E Joyce, Daniel N A Bolon","doi":"10.1091/mbc.E24-07-0309","DOIUrl":"10.1091/mbc.E24-07-0309","url":null,"abstract":"Dominant negative (DN) mutations provide valuable tools for investigating protein mechanisms but can be difficult to isolate because of their toxic effects. We used a mutational scanning approach to identify DN mutations in yeast Hsp90. In a previous mutational scan of the ATPase domain of Hsp90, we noticed that many mutations were at very low frequency after outgrowth in cells coexpressing wildtype Hsp90. Most of these depleted variants were located at the hinge of a lid that closes over ATP. To quantify toxic effects in the hinge regions, we performed mutational scanning using an inducible promoter and identified 113 variants with strong toxic effects. We analyzed individual DN mutations in detail and found that addition of the E33A mutation that prevents ATP hydrolysis by Hsp90 abrogated the DN phenotype. FRET assays performed on individual DN mutants indicate the linkage between ATPase activity and formation of the closed structure is disrupted. DN Hsp90 decreased the expression level of two model Hsp90 clients, glucocorticoid receptor (GR) and v-src kinase. Using MG132, we found that GR was rapidly destabilized in a proteasome-dependent manner. Biochemical analyses indicate that ATP hydrolysis by Hsp90 from open conformations can lead to ubiquitin-dependent client degradation.","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"ar5"},"PeriodicalIF":3.1,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11742116/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142682089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0