1
|
Jackson JA, Denk-Lobnig M, Kitzinger KA, Martin AC. Change in RhoGAP and RhoGEF availability drives transitions in cortical patterning and excitability in Drosophila. Curr Biol 2024; 34:2132-2146.e5. [PMID: 38688282 PMCID: PMC11111359 DOI: 10.1016/j.cub.2024.04.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 02/13/2024] [Accepted: 04/09/2024] [Indexed: 05/02/2024]
Abstract
Actin cortex patterning and dynamics are critical for cell shape changes. These dynamics undergo transitions during development, often accompanying changes in collective cell behavior. Although mechanisms have been established for individual cells' dynamic behaviors, the mechanisms and specific molecules that result in developmental transitions in vivo are still poorly understood. Here, we took advantage of two developmental systems in Drosophila melanogaster to identify conditions that altered cortical patterning and dynamics. We identified a Rho guanine nucleotide exchange factor (RhoGEF) and Rho GTPase activating protein (RhoGAP) pair required for actomyosin waves in egg chambers. Specifically, depletion of the RhoGEF, Ect2, or the RhoGAP, RhoGAP15B, disrupted actomyosin wave induction, and both proteins relocalized from the nucleus to the cortex preceding wave formation. Furthermore, we found that overexpression of a different RhoGEF and RhoGAP pair, RhoGEF2 and Cumberland GAP (C-GAP), resulted in actomyosin waves in the early embryo, during which RhoA activation precedes actomyosin assembly by ∼4 s. We found that C-GAP was recruited to actomyosin waves, and disrupting F-actin polymerization altered the spatial organization of both RhoA signaling and the cytoskeleton in waves. In addition, disrupting F-actin dynamics increased wave period and width, consistent with a possible role for F-actin in promoting delayed negative feedback. Overall, we showed a mechanism involved in inducing actomyosin waves that is essential for oocyte development and is general to other cell types, such as epithelial and syncytial cells.
Collapse
Affiliation(s)
- Jonathan A Jackson
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139, USA; Graduate Program in Biophysics, Harvard University, 86 Brattle Street, Cambridge, MA 02138, USA
| | - Marlis Denk-Lobnig
- Department of Biophysics, University of Michigan, 1109 Geddes Ave., Ann Arbor, MI 48109, USA
| | - Katherine A Kitzinger
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139, USA
| | - Adam C Martin
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139, USA.
| |
Collapse
|
2
|
Ventura Santos C, Rogers SL, Carter AP. CryoET shows cofilactin filaments inside the microtubule lumen. EMBO Rep 2023; 24:e57264. [PMID: 37702953 PMCID: PMC10626427 DOI: 10.15252/embr.202357264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 08/25/2023] [Accepted: 08/30/2023] [Indexed: 09/14/2023] Open
Abstract
Cytoplasmic microtubules are tubular polymers that can harbor small proteins or filaments inside their lumen. The identities of these objects and mechanisms for their accumulation have not been conclusively established. Here, we used cryogenic electron tomography of Drosophila S2 cell protrusions and found filaments inside the microtubule lumen, which resemble those reported recently in human HAP1 cells. The frequency of these filaments increased upon inhibition of the sarco/endoplasmic reticulum Ca2+ ATPase with the small molecule drug thapsigargin. Subtomogram averaging showed that the luminal filaments adopt a helical structure reminiscent of cofilin-bound actin (cofilactin). Consistent with this, we observed cofilin dephosphorylation, an activating modification, in cells under the same conditions that increased luminal filament occurrence. Furthermore, RNA interference knock-down of cofilin reduced the frequency of luminal filaments with cofilactin morphology. These results suggest that cofilin activation stimulates its accumulation on actin filaments inside the microtubule lumen.
Collapse
Affiliation(s)
| | - Stephen L Rogers
- Department of Biology and Integrative Program for Biological and Genome Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | | |
Collapse
|
3
|
Cheikh MI, Tchoufag J, Osterfield M, Dean K, Bhaduri S, Zhang C, Mandadapu KK, Doubrovinski K. A comprehensive model of Drosophila epithelium reveals the role of embryo geometry and cell topology in mechanical responses. eLife 2023; 12:e85569. [PMID: 37782009 PMCID: PMC10584372 DOI: 10.7554/elife.85569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 09/29/2023] [Indexed: 10/03/2023] Open
Abstract
In order to understand morphogenesis, it is necessary to know the material properties or forces shaping the living tissue. In spite of this need, very few in vivo measurements are currently available. Here, using the early Drosophila embryo as a model, we describe a novel cantilever-based technique which allows for the simultaneous quantification of applied force and tissue displacement in a living embryo. By analyzing data from a series of experiments in which embryonic epithelium is subjected to developmentally relevant perturbations, we conclude that the response to applied force is adiabatic and is dominated by elastic forces and geometric constraints, or system size effects. Crucially, computational modeling of the experimental data indicated that the apical surface of the epithelium must be softer than the basal surface, a result which we confirmed experimentally. Further, we used the combination of experimental data and comprehensive computational model to estimate the elastic modulus of the apical surface and set a lower bound on the elastic modulus of the basal surface. More generally, our investigations revealed important general features that we believe should be more widely addressed when quantitatively modeling tissue mechanics in any system. Specifically, different compartments of the same cell can have very different mechanical properties; when they do, they can contribute differently to different mechanical stimuli and cannot be merely averaged together. Additionally, tissue geometry can play a substantial role in mechanical response, and cannot be neglected.
Collapse
Affiliation(s)
- Mohamad Ibrahim Cheikh
- Department of Biophysics, University of Texas Southwestern Medical CenterDallasUnited States
| | - Joel Tchoufag
- Department of Chemical and Biomolecular Engineering, University of California, BerkeleyBerkeleyUnited States
- Chemical Sciences Division, Lawrence Berkeley National LaboratoryBerkeleyUnited States
| | - Miriam Osterfield
- Department of Biophysics, University of Texas Southwestern Medical CenterDallasUnited States
| | - Kevin Dean
- Department of Bioinformatics, University of Texas Southwestern Medical CenterDallasUnited States
| | - Swayamdipta Bhaduri
- Department of Biophysics, University of Texas Southwestern Medical CenterDallasUnited States
| | - Chuzhong Zhang
- Department of Material Science and Engineering, University of Texas at ArlingtonArlingtonUnited States
| | - Kranthi Kiran Mandadapu
- Department of Chemical and Biomolecular Engineering, University of California, BerkeleyBerkeleyUnited States
- Chemical Sciences Division, Lawrence Berkeley National LaboratoryBerkeleyUnited States
| | - Konstantin Doubrovinski
- Department of Biophysics, University of Texas Southwestern Medical CenterDallasUnited States
| |
Collapse
|
4
|
Du WW, Qadir J, Du KY, Chen Y, Wu N, Yang BB. Nuclear Actin Polymerization Regulates Cell Epithelial-Mesenchymal Transition. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2300425. [PMID: 37566765 PMCID: PMC10558697 DOI: 10.1002/advs.202300425] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 06/28/2023] [Indexed: 08/13/2023]
Abstract
Current studies on actin function primarily rely on cytoplasmic actin due to the absence of cellular models specifically expressing nuclear actin. Here, cell models capable of expressing varying levels of nuclear F/G-actin are generated and a significant role of nuclear actin in the regulation of epithelial-mesenchymal transition (EMT) is uncovered. Through immunoprecipitation and mass spectrometry analyses, distinct binding partners for nuclear F-actin (β-catenin, SMAD2, and SMAD3) and nuclear G-actin (MYBBP1A, NKRF, and MYPOP) are investigated, which respectively modulate EMT-promoting and EMT-repressing transcriptional events. While nuclear F-actin promotes EMT with enhanced cell migration, survival, and elongated mesenchymal morphology, nuclear G-actin represses EMT and related cell activities. Mechanistically, nuclear F-actin enhances β-catenin, SMAD2, and SMAD3 expression and stability in the nuclei, while nuclear G-actin increases MYBBP1A, NKRF, and MYPOP expression and stability in the nuclei. The association between nuclear F/G-actin and N-cadherin/E-cadherin in the cell lines (in vitro), and increased nuclear actin polymerization in the wound healing cells (in vivo) affirm a significant role of nuclear actin in EMT regulation. With evidence of nuclear actin polymerization and EMT during development, and irregularities in disease states such as cancer and fibrosis, targeting nuclear actin dynamics to trigger dysregulated EMT warrants ongoing study.
Collapse
Affiliation(s)
- William W. Du
- Sunnybrook Research Instituteand Department of Laboratory Medicine and PathobiologyUniversity of TorontoTorontoONM4N3M5Canada
| | - Javeria Qadir
- Sunnybrook Research Instituteand Department of Laboratory Medicine and PathobiologyUniversity of TorontoTorontoONM4N3M5Canada
| | - Kevin Y. Du
- Sunnybrook Research Instituteand Department of Laboratory Medicine and PathobiologyUniversity of TorontoTorontoONM4N3M5Canada
| | - Yu Chen
- Sunnybrook Research Instituteand Department of Laboratory Medicine and PathobiologyUniversity of TorontoTorontoONM4N3M5Canada
| | - Nan Wu
- Sunnybrook Research Instituteand Department of Laboratory Medicine and PathobiologyUniversity of TorontoTorontoONM4N3M5Canada
| | - Burton B. Yang
- Sunnybrook Research Instituteand Department of Laboratory Medicine and PathobiologyUniversity of TorontoTorontoONM4N3M5Canada
| |
Collapse
|
5
|
Wang C, Du M, Jiang Z, Cong R, Wang W, Zhang G, Li L. Comparative proteomic and phosphoproteomic analysis reveals differential heat response mechanism in two congeneric oyster species. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 263:115197. [PMID: 37451098 DOI: 10.1016/j.ecoenv.2023.115197] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 06/17/2023] [Accepted: 06/26/2023] [Indexed: 07/18/2023]
Abstract
High-temperature stress caused by global climate change poses a significant threat to marine ectotherms. This study investigated the role of protein phosphorylation modifications in the molecular regulation network under heat stress in oysters, which are representative intertidal organisms that experience considerable temperature changes. Firstly, the study compared the extent of thermal damage between two congeneric oyster species, the relative heat-tolerant Crassostrea angulata (C. angulata) and heat-sensitive Crassostrea gigas (C. gigas), under sublethal temperature (37 °C) for 12 h, using various physiological and biochemical methods. Subsequently, the comparative proteomic and phosphoproteomic analyses revealed that high-temperature considerably regulated signal transduction, energy metabolism, protein synthesis, cell survival and apoptosis, and cytoskeleton remodeling through phosphorylation modifications of related receptors and kinases. Furthermore, the protein kinase A, mitogen-activated protein kinase 1, tyrosine-protein kinase Src, and serine/threonine kinase AKT, exhibiting differential phosphorylation modification patterns, were identified as hub regulators that may enhance glycolysis and TCA cycle to increase the energy supply, distribute protein synthesis, inhibit Caspase-dependent apoptosis activated by endogenous mitochondrial cytochrome release and maintain cytoskeletal stability, ultimately shaping the higher thermal resistance of C. angulata. This study represents the first investigation of protein phosphorylation dynamics in marine invertebrates under heat stress, reveals the molecular mechanisms underlying the differential thermal responses between two Crassostrea oysters at the phosphorylation level, and provides new insights into understanding phosphorylation-mediated molecular responses in marine organisms during environmental changes and predicting the adaptive potential in the context of global warming.
Collapse
Affiliation(s)
- Chaogang Wang
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Biology and Biotechnology, Laoshan Laboratory, Qingdao, China; University of Chinese Academy of Sciences, Beijing, China
| | - Mingyang Du
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Biology and Biotechnology, Laoshan Laboratory, Qingdao, China; University of Chinese Academy of Sciences, Beijing, China
| | - Zhuxiang Jiang
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Biology and Biotechnology, Laoshan Laboratory, Qingdao, China; University of Chinese Academy of Sciences, Beijing, China
| | - Rihao Cong
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Biology and Biotechnology, Laoshan Laboratory, Qingdao, China; National and Local Joint Engineering Laboratory of Ecological Mariculture, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Shandong Technology Innovation Center of Oyster Seed Industry, Qingdao, China
| | - Wei Wang
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Fisheries Science and Food Production Processes, Laoshan Laboratory, Qingdao, China; National and Local Joint Engineering Laboratory of Ecological Mariculture, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Shandong Technology Innovation Center of Oyster Seed Industry, Qingdao, China
| | - Guofan Zhang
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Biology and Biotechnology, Laoshan Laboratory, Qingdao, China; Key Laboratory of Breeding Biotechnology and Sustainable Aquaculture, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China; National and Local Joint Engineering Laboratory of Ecological Mariculture, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Shandong Technology Innovation Center of Oyster Seed Industry, Qingdao, China
| | - Li Li
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; University of Chinese Academy of Sciences, Beijing, China; Key Laboratory of Breeding Biotechnology and Sustainable Aquaculture, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China; Laboratory for Marine Fisheries Science and Food Production Processes, Laoshan Laboratory, Qingdao, China; National and Local Joint Engineering Laboratory of Ecological Mariculture, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Shandong Technology Innovation Center of Oyster Seed Industry, Qingdao, China.
| |
Collapse
|
6
|
Sokac AM, Biel N, De Renzis S. Membrane-actin interactions in morphogenesis: Lessons learned from Drosophila cellularization. Semin Cell Dev Biol 2023; 133:107-122. [PMID: 35396167 PMCID: PMC9532467 DOI: 10.1016/j.semcdb.2022.03.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 03/18/2022] [Accepted: 03/21/2022] [Indexed: 01/12/2023]
Abstract
During morphogenesis, changes in the shapes of individual cells are harnessed to mold an entire tissue. These changes in cell shapes require the coupled remodeling of the plasma membrane and underlying actin cytoskeleton. In this review, we highlight cellularization of the Drosophila embryo as a model system to uncover principles of how membrane and actin dynamics are co-regulated in space and time to drive morphogenesis.
Collapse
Affiliation(s)
- Anna Marie Sokac
- Department of Cell and Developmental Biology, University of Illinois at Urbana Champaign, Urbana, IL 61801, USA; Graduate Program in Integrative and Molecular Biomedical Sciences, Baylor College of Medicine, Houston, TX 77030, USA.
| | - Natalie Biel
- Department of Cell and Developmental Biology, University of Illinois at Urbana Champaign, Urbana, IL 61801, USA; Graduate Program in Integrative and Molecular Biomedical Sciences, Baylor College of Medicine, Houston, TX 77030, USA
| | - Stefano De Renzis
- European Molecular Biology Laboratory Heidelberg, 69117 Heidelberg, Germany
| |
Collapse
|
7
|
Wurz AI, Schulz AM, O’Bryant CT, Sharp JF, Hughes RM. Cytoskeletal dysregulation and neurodegenerative disease: Formation, monitoring, and inhibition of cofilin-actin rods. Front Cell Neurosci 2022; 16:982074. [PMID: 36212686 PMCID: PMC9535683 DOI: 10.3389/fncel.2022.982074] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 08/31/2022] [Indexed: 12/04/2022] Open
Abstract
The presence of atypical cytoskeletal dynamics, structures, and associated morphologies is a common theme uniting numerous diseases and developmental disorders. In particular, cytoskeletal dysregulation is a common cellular feature of Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease. While the numerous activators and inhibitors of dysregulation present complexities for characterizing these elements as byproducts or initiators of the disease state, it is increasingly clear that a better understanding of these anomalies is critical for advancing the state of knowledge and plan of therapeutic attack. In this review, we focus on the hallmarks of cytoskeletal dysregulation that are associated with cofilin-linked actin regulation, with a particular emphasis on the formation, monitoring, and inhibition of cofilin-actin rods. We also review actin-associated proteins other than cofilin with links to cytoskeleton-associated neurodegenerative processes, recognizing that cofilin-actin rods comprise one strand of a vast web of interactions that occur as a result of cytoskeletal dysregulation. Our aim is to present a current perspective on cytoskeletal dysregulation, connecting recent developments in our understanding with emerging strategies for biosensing and biomimicry that will help shape future directions of the field.
Collapse
Affiliation(s)
- Anna I. Wurz
- Department of Chemistry, East Carolina University, Greenville, NC, United States
| | - Anna M. Schulz
- Department of Chemistry, East Carolina University, Greenville, NC, United States
| | - Collin T. O’Bryant
- Department of Chemistry, East Carolina University, Greenville, NC, United States
| | - Josephine F. Sharp
- Department of Chemistry, Notre Dame College, South Euclid, OH, United States
| | - Robert M. Hughes
- Department of Chemistry, East Carolina University, Greenville, NC, United States
- *Correspondence: Robert M. Hughes,
| |
Collapse
|
8
|
Gunasekaran S, Miyagawa Y, Miyamoto K. Actin nucleoskeleton in embryonic development and cellular differentiation. Curr Opin Cell Biol 2022; 76:102100. [DOI: 10.1016/j.ceb.2022.102100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 03/28/2022] [Accepted: 04/22/2022] [Indexed: 11/03/2022]
|
9
|
Record J, Saeed MB, Venit T, Percipalle P, Westerberg LS. Journey to the Center of the Cell: Cytoplasmic and Nuclear Actin in Immune Cell Functions. Front Cell Dev Biol 2021; 9:682294. [PMID: 34422807 PMCID: PMC8375500 DOI: 10.3389/fcell.2021.682294] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 07/06/2021] [Indexed: 12/12/2022] Open
Abstract
Actin cytoskeletal dynamics drive cellular shape changes, linking numerous cell functions to physiological and pathological cues. Mutations in actin regulators that are differentially expressed or enriched in immune cells cause severe human diseases known as primary immunodeficiencies underscoring the importance of efficienct actin remodeling in immune cell homeostasis. Here we discuss recent findings on how immune cells sense the mechanical properties of their environement. Moreover, while the organization and biochemical regulation of cytoplasmic actin have been extensively studied, nuclear actin reorganization is a rapidly emerging field that has only begun to be explored in immune cells. Based on the critical and multifaceted contributions of cytoplasmic actin in immune cell functionality, nuclear actin regulation is anticipated to have a large impact on our understanding of immune cell development and functionality.
Collapse
Affiliation(s)
- Julien Record
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
| | - Mezida B. Saeed
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
| | - Tomas Venit
- Science Division, Biology Program, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates
| | - Piergiorgio Percipalle
- Science Division, Biology Program, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Lisa S. Westerberg
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
| |
Collapse
|
10
|
Schroeder CM, Tomlin SA, Mejia Natividad I, Valenzuela JR, Young JM, Malik HS. An actin-related protein that is most highly expressed in Drosophila testes is critical for embryonic development. eLife 2021; 10:71279. [PMID: 34282725 PMCID: PMC8291977 DOI: 10.7554/elife.71279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 06/20/2021] [Indexed: 12/25/2022] Open
Abstract
Most actin-related proteins (Arps) are highly conserved and carry out well-defined cellular functions in eukaryotes. However, many lineages like Drosophila and mammals encode divergent non-canonical Arps whose roles remain unknown. To elucidate the function of non-canonical Arps, we focus on Arp53D, which is highly expressed in testes and retained throughout Drosophila evolution. We show that Arp53D localizes to fusomes and actin cones, two germline-specific actin structures critical for sperm maturation, via a unique N-terminal tail. Surprisingly, we find that male fertility is not impaired upon Arp53D loss, yet population cage experiments reveal that Arp53D is required for optimal fitness in Drosophila melanogaster. To reconcile these findings, we focus on Arp53D function in ovaries and embryos where it is only weakly expressed. We find that under heat stress Arp53D-knockout (KO) females lay embryos with reduced nuclear integrity and lower viability; these defects are further exacerbated in Arp53D-KO embryos. Thus, despite its relatively recent evolution and primarily testis-specific expression, non-canonical Arp53D is required for optimal embryonic development in Drosophila.
Collapse
Affiliation(s)
- Courtney M Schroeder
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States
| | - Sarah A Tomlin
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States.,Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, United States
| | - Isabel Mejia Natividad
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States.,Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, United States
| | - John R Valenzuela
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States
| | - Janet M Young
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States
| | - Harmit S Malik
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States.,Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, United States
| |
Collapse
|
11
|
New Insights into Cellular Functions of Nuclear Actin. BIOLOGY 2021; 10:biology10040304. [PMID: 33916969 PMCID: PMC8067577 DOI: 10.3390/biology10040304] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 03/30/2021] [Accepted: 04/01/2021] [Indexed: 12/12/2022]
Abstract
Simple Summary It is well known that actin forms a cytoplasmic network of microfilaments, the part of the cytoskeleton, in the cytoplasm of eukaryotic cells. The presence of nuclear actin was elusive for a very long time. Now, there is a very strong evidence that actin plays many important roles in the nucleus. Here, we discuss the recently discovered functions of the nuclear actin pool. Actin does not have nuclear localization signal (NLS), so its import to the nucleus is facilitated by the NLS-containing proteins. Nuclear actin plays a role in the maintenance of the nuclear structure and the nuclear envelope breakdown. It is also involved in chromatin remodeling, and chromatin and nucleosome movement necessary for DNA recombination, repair, and the initiation of transcription. It also binds RNA polymerases, promoting transcription. Because of the multifaceted role of nuclear actin, the future challenge will be to further define its functions in various cellular processes and diseases. Abstract Actin is one of the most abundant proteins in eukaryotic cells. There are different pools of nuclear actin often undetectable by conventional staining and commercial antibodies used to identify cytoplasmic actin. With the development of more sophisticated imaging and analytical techniques, it became clear that nuclear actin plays a crucial role in shaping the chromatin, genomic, and epigenetic landscape, transcriptional regulation, and DNA repair. This multifaceted role of nuclear actin is not only important for the function of the individual cell but also for the establishment of cell fate, and tissue and organ differentiation during development. Moreover, the changes in the nuclear, chromatin, and genomic architecture are preamble to various diseases. Here, we discuss some of the newly described functions of nuclear actin.
Collapse
|
12
|
Yin C, Liu J, Chang Z, He B, Yang Y, Zhao R. Heat exposure impairs porcine oocyte quality with suppressed actin expression in cumulus cells and disrupted F-actin formation in transzonal projections. J Anim Sci Biotechnol 2020; 11:71. [PMID: 32647569 PMCID: PMC7336674 DOI: 10.1186/s40104-020-00477-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 05/17/2020] [Indexed: 12/29/2022] Open
Abstract
Background Transzonal projections (TZPs) constitute a structural basis for the communication between the oocyte and its surrounding cumulus cells (CCs), which play critical roles in promoting the oocyte maturation. Previously we found that heat stress (HS) causes loss of TZPs in porcine cumulus-oocyte complexes (COCs) with decreased density of filamentous actin (F-actin). However, the time-course responses of F-actin and its monomeric actins (β-actin and γ-actin) during the in vitro maturation of oocytes remain unclear. Results In this study, excised porcine ovaries were exposed to HS at 41.5 °C for 1 h before COCs were isolated and matured in vitro for 44 h. HS significantly reduced oocyte quality, characterized by impaired cumulus expansion, delayed meiotic resumption and lower survival rate and polar body extrusion rate, as well as decreased expression of mitochondrial DNA-encoded genes and elevated mitochondrial reactive oxygen species concentration. Expression of β-actin and γ-actin in CCs increased gradually with oocytes maturation, which was significantly reduced in HS group, especially at 24 h and/or 44 h of in vitro maturation. By contrast, the number of TZPs and the fluorescence intensity of F-actin in zona pellucida decreased gradually during oocytes maturation, which were significantly reduced by HS at 24 h of in vitro maturation. Moreover, colocalization analyses revealed both β-actin and γ-actin contribute to the F-actin formation in porcine TZPs, and the colocalization of F-actin with GJ protein connexin 45 was significantly reduced in heat-exposed COCs. Conclusions The results indicate that the suppression of actin expressions in CCs, which may lead to the F-actin unstabilization in TZPs, will subsequently contribute to the compromised quality of oocytes under HS.
Collapse
Affiliation(s)
- Chao Yin
- MOE Joint International Research Laboratory of Animal Health & Food Safety, Nanjing Agricultural University, Nanjing, Jiangsu China.,Key Laboratory of Animal Physiology and Biochemistry, Ministry of Agriculture, Nanjing Agricultural University, No.1 Weigang Road, Nanjing, 210095 China.,College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi China
| | - Jie Liu
- MOE Joint International Research Laboratory of Animal Health & Food Safety, Nanjing Agricultural University, Nanjing, Jiangsu China.,Key Laboratory of Animal Physiology and Biochemistry, Ministry of Agriculture, Nanjing Agricultural University, No.1 Weigang Road, Nanjing, 210095 China
| | - Zhanglin Chang
- MOE Joint International Research Laboratory of Animal Health & Food Safety, Nanjing Agricultural University, Nanjing, Jiangsu China.,Key Laboratory of Animal Physiology and Biochemistry, Ministry of Agriculture, Nanjing Agricultural University, No.1 Weigang Road, Nanjing, 210095 China
| | - Bin He
- MOE Joint International Research Laboratory of Animal Health & Food Safety, Nanjing Agricultural University, Nanjing, Jiangsu China.,Key Laboratory of Animal Physiology and Biochemistry, Ministry of Agriculture, Nanjing Agricultural University, No.1 Weigang Road, Nanjing, 210095 China
| | - Yang Yang
- MOE Joint International Research Laboratory of Animal Health & Food Safety, Nanjing Agricultural University, Nanjing, Jiangsu China.,Key Laboratory of Animal Physiology and Biochemistry, Ministry of Agriculture, Nanjing Agricultural University, No.1 Weigang Road, Nanjing, 210095 China
| | - Ruqian Zhao
- MOE Joint International Research Laboratory of Animal Health & Food Safety, Nanjing Agricultural University, Nanjing, Jiangsu China.,Key Laboratory of Animal Physiology and Biochemistry, Ministry of Agriculture, Nanjing Agricultural University, No.1 Weigang Road, Nanjing, 210095 China
| |
Collapse
|
13
|
Biel N, Figard L, Sokac AM. Imaging Intranuclear Actin Rods in Live Heat Stressed Drosophila Embryos. J Vis Exp 2020. [PMID: 32478727 DOI: 10.3791/61297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The purpose of this protocol is to visualize intranuclear actin rods that assemble in live Drosophila melanogaster embryos following heat stress. Actin rods are a hallmark of a conserved, inducible Actin Stress Response (ASR) that accompanies human pathologies, including neurodegenerative disease. Previously, we showed that the ASR contributes to morphogenesis failures and reduced viability of developing embryos. This protocol allows the continued study of mechanisms underlying actin rod assembly and the ASR in a model system that is highly amenable to imaging, genetics and biochemistry. Embryos are collected and mounted on a coverslip to prepare them for injection. Rhodamine-conjugated globular actin (G-actinRed) is diluted and loaded into a microneedle. A single injection is made into the center of each embryo. After injection, embryos are incubated at elevated temperature and intranuclear actin rods are then visualized by confocal microscopy. Fluorescence recovery after photobleaching (FRAP) experiments may be performed on the actin rods; and other actin-rich structures in the cytoplasm can also be imaged. We find that G-actinRed polymerizes like endogenous G-actin and does not, on its own, interfere with normal embryo development. One limitation of this protocol is that care must be taken during injection to avoid serious injury to the embryo. However, with practice, injecting G-actinRed into Drosophila embryos is a fast and reliable way to visualize actin rods and can easily be used with flies of any genotype or with the introduction of other cellular stresses, including hypoxia and oxidative stress.
Collapse
Affiliation(s)
- Natalie Biel
- Integrative Molecular and Biomedical Sciences, Baylor College of Medicine; Department of Cell and Molecular Biology, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign
| | - Lauren Figard
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine
| | - Anna Marie Sokac
- Integrative Molecular and Biomedical Sciences, Baylor College of Medicine; Department of Cell and Molecular Biology, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign; Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine;
| |
Collapse
|
14
|
Hyrskyluoto A, Vartiainen MK. Regulation of nuclear actin dynamics in development and disease. Curr Opin Cell Biol 2020; 64:18-24. [PMID: 32088545 DOI: 10.1016/j.ceb.2020.01.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 01/17/2020] [Accepted: 01/22/2020] [Indexed: 12/21/2022]
Abstract
Actin has essential functions both in the cytoplasm and in the nucleus, where it has been linked to key nuclear processes, from transcription to DNA damage response. The multifunctional nature of actin suggests that the cell must contain mechanisms to accurately control the cellular actin balance. Indeed, recent results have demonstrated that nuclear actin levels fluctuate to regulate the transcriptional activity of the cell and that controlled nuclear actin polymerization is required for transcription activation, cell cycle progression, and DNA repair. Intriguingly, aberrant nuclear actin regulation has been observed, for example, in cancer, signifying the importance of this process for cellular homeostasis. This review discussed the latest research on how nuclear actin is regulated, and how this influences actin-dependent nuclear processes.
Collapse
Affiliation(s)
- Alise Hyrskyluoto
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, 00014, Helsinki, Finland
| | - Maria K Vartiainen
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, 00014, Helsinki, Finland.
| |
Collapse
|