1
|
Berg C, Sieber M, Sun J. Finishing the egg. Genetics 2024; 226:iyad183. [PMID: 38000906 PMCID: PMC10763546 DOI: 10.1093/genetics/iyad183] [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: 07/05/2023] [Accepted: 09/27/2023] [Indexed: 11/26/2023] Open
Abstract
Gamete development is a fundamental process that is highly conserved from early eukaryotes to mammals. As germ cells develop, they must coordinate a dynamic series of cellular processes that support growth, cell specification, patterning, the loading of maternal factors (RNAs, proteins, and nutrients), differentiation of structures to enable fertilization and ensure embryonic survival, and other processes that make a functional oocyte. To achieve these goals, germ cells integrate a complex milieu of environmental and developmental signals to produce fertilizable eggs. Over the past 50 years, Drosophila oogenesis has risen to the forefront as a system to interrogate the sophisticated mechanisms that drive oocyte development. Studies in Drosophila have defined mechanisms in germ cells that control meiosis, protect genome integrity, facilitate mRNA trafficking, and support the maternal loading of nutrients. Work in this system has provided key insights into the mechanisms that establish egg chamber polarity and patterning as well as the mechanisms that drive ovulation and egg activation. Using the power of Drosophila genetics, the field has begun to define the molecular mechanisms that coordinate environmental stresses and nutrient availability with oocyte development. Importantly, the majority of these reproductive mechanisms are highly conserved throughout evolution, and many play critical roles in the development of somatic tissues as well. In this chapter, we summarize the recent progress in several key areas that impact egg chamber development and ovulation. First, we discuss the mechanisms that drive nutrient storage and trafficking during oocyte maturation and vitellogenesis. Second, we examine the processes that regulate follicle cell patterning and how that patterning impacts the construction of the egg shell and the establishment of embryonic polarity. Finally, we examine regulatory factors that control ovulation, egg activation, and successful fertilization.
Collapse
Affiliation(s)
- Celeste Berg
- Department of Genome Sciences, University of Washington, Seattle, WA 98195-5065USA
| | - Matthew Sieber
- Department of Physiology, UT Southwestern Medical Center, Dallas, TX 75390USA
| | - Jianjun Sun
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, CT 06269USA
| |
Collapse
|
2
|
Feijão T, Marques B, Silva RD, Carvalho C, Sobral D, Matos R, Tan T, Pereira A, Morais-de-Sá E, Maiato H, DeLuca SZ, Martinho RG. Polycomb group (PcG) proteins prevent the assembly of abnormal synaptonemal complex structures during meiosis. Proc Natl Acad Sci U S A 2022; 119:e2204701119. [PMID: 36215502 PMCID: PMC9586294 DOI: 10.1073/pnas.2204701119] [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: 03/16/2022] [Accepted: 07/18/2022] [Indexed: 11/18/2022] Open
Abstract
The synaptonemal complex (SC) is a proteinaceous scaffold that is assembled between paired homologous chromosomes during the onset of meiosis. Timely expression of SC coding genes is essential for SC assembly and successful meiosis. However, SC components have an intrinsic tendency to self-organize into abnormal repetitive structures, which are not assembled between the paired homologs and whose formation is potentially deleterious for meiosis and gametogenesis. This creates an interesting conundrum, where SC genes need to be robustly expressed during meiosis, but their expression must be carefully regulated to prevent the formation of anomalous SC structures. In this manuscript, we show that the Polycomb group protein Sfmbt, the Drosophila ortholog of human MBTD1 and L3MBTL2, is required to avoid excessive expression of SC genes during prophase I. Although SC assembly is normal after Sfmbt depletion, SC disassembly is abnormal with the formation of multiple synaptonemal complexes (polycomplexes) within the oocyte. Overexpression of the SC gene corona and depletion of other Polycomb group proteins are similarly associated with polycomplex formation during SC disassembly. These polycomplexes are highly dynamic and have a well-defined periodic structure. Further confirming the importance of Sfmbt, germ line depletion of this protein is associated with significant metaphase I defects and a reduction in female fertility. Since transcription of SC genes mostly occurs during early prophase I, our results suggest a role of Sfmbt and other Polycomb group proteins in downregulating the expression of these and other early prophase I genes during later stages of meiosis.
Collapse
Affiliation(s)
- Tália Feijão
- Algarve Biomedical Center Research Institute, Universidade do Algarve, 8005-139 Faro, Portugal
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Porto, 4200-135 Portugal
- Department of Medical Sciences and Institute for Biomedicine, Universidade de Aveiro, 3810-193 Aveiro, Portugal
| | - Bruno Marques
- Algarve Biomedical Center Research Institute, Universidade do Algarve, 8005-139 Faro, Portugal
| | - Rui D. Silva
- Algarve Biomedical Center Research Institute, Universidade do Algarve, 8005-139 Faro, Portugal
- Faculty of Medicine and Biomedical Sciences, Universidade do Algarve, 8005-139 Faro, Portugal
| | - Célia Carvalho
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Daniel Sobral
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2819-516 Caparica, Portugal
- Applied Molecular Biosciences Unit (UCIBIO), Department of Life Sciences, School of Science and Technology, NOVA University Lisbon, Caparica, 2819-516 Portugal
| | - Ricardo Matos
- Algarve Biomedical Center Research Institute, Universidade do Algarve, 8005-139 Faro, Portugal
| | - Tian Tan
- Department of Biology, Brandeis University, Waltham, MA 02453
| | - António Pereira
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Porto, 4200-135 Portugal
| | - Eurico Morais-de-Sá
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Porto, 4200-135 Portugal
| | - Hélder Maiato
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Porto, 4200-135 Portugal
| | | | - Rui Gonçalo Martinho
- Algarve Biomedical Center Research Institute, Universidade do Algarve, 8005-139 Faro, Portugal
- Department of Medical Sciences and Institute for Biomedicine, Universidade de Aveiro, 3810-193 Aveiro, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| |
Collapse
|
3
|
The structure and function of protein kinase C-related kinases (PRKs). Biochem Soc Trans 2021; 49:217-235. [PMID: 33522581 PMCID: PMC7925014 DOI: 10.1042/bst20200466] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 12/29/2020] [Accepted: 01/07/2021] [Indexed: 11/17/2022]
Abstract
The protein kinase C-related kinase (PRK) family of serine/threonine kinases, PRK1, PRK2 and PRK3, are effectors for the Rho family small G proteins. An array of studies have linked these kinases to multiple signalling pathways and physiological roles, but while PRK1 is relatively well-characterized, the entire PRK family remains understudied. Here, we provide a holistic overview of the structure and function of PRKs and describe the molecular events that govern activation and autoregulation of catalytic activity, including phosphorylation, protein interactions and lipid binding. We begin with a structural description of the regulatory and catalytic domains, which facilitates the understanding of their regulation in molecular detail. We then examine their diverse physiological roles in cytoskeletal reorganization, cell adhesion, chromatin remodelling, androgen receptor signalling, cell cycle regulation, the immune response, glucose metabolism and development, highlighting isoform redundancy but also isoform specificity. Finally, we consider the involvement of PRKs in pathologies, including cancer, heart disease and bacterial infections. The abundance of PRK-driven pathologies suggests that these enzymes will be good therapeutic targets and we briefly report some of the progress to date.
Collapse
|
4
|
Rathore OS, Silva RD, Ascensão-Ferreira M, Matos R, Carvalho C, Marques B, Tiago MN, Prudêncio P, Andrade RP, Roignant JY, Barbosa-Morais NL, Martinho RG. NineTeen Complex-subunit Salsa is required for efficient splicing of a subset of introns and dorsal-ventral patterning. RNA (NEW YORK, N.Y.) 2020; 26:1935-1956. [PMID: 32963109 PMCID: PMC7668242 DOI: 10.1261/rna.077446.120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 09/07/2020] [Indexed: 06/11/2023]
Abstract
The NineTeen Complex (NTC), also known as pre-mRNA-processing factor 19 (Prp19) complex, regulates distinct spliceosome conformational changes necessary for splicing. During Drosophila midblastula transition, splicing is particularly sensitive to mutations in NTC-subunit Fandango, which suggests differential requirements of NTC during development. We show that NTC-subunit Salsa, the Drosophila ortholog of human RNA helicase Aquarius, is rate-limiting for splicing of a subset of small first introns during oogenesis, including the first intron of gurken Germline depletion of Salsa and splice site mutations within gurken first intron impair both adult female fertility and oocyte dorsal-ventral patterning, due to an abnormal expression of Gurken. Supporting causality, the fertility and dorsal-ventral patterning defects observed after Salsa depletion could be suppressed by the expression of a gurken construct without its first intron. Altogether, our results suggest that one of the key rate-limiting functions of Salsa during oogenesis is to ensure the correct expression and efficient splicing of the first intron of gurken mRNA. Retention of gurken first intron compromises the function of this gene most likely because it undermines the correct structure and function of the transcript 5'UTR.
Collapse
Affiliation(s)
- Om Singh Rathore
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
| | - Rui D Silva
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
| | - Mariana Ascensão-Ferreira
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Ricardo Matos
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
| | - Célia Carvalho
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Bruno Marques
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
| | - Margarida N Tiago
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
| | - Pedro Prudêncio
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Raquel P Andrade
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
- Department of Medicine and Biomedical Sciences and Algarve Biomedical Center, Universidade do Algarve, 8005-139 Faro, Portugal
| | - Jean-Yves Roignant
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, CH-1015 Lausanne, Switzerland
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-University Mainz, 55128 Mainz, Germany
| | - Nuno L Barbosa-Morais
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Rui Gonçalo Martinho
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
- Department of Medical Sciences and Institute for Biomedicine (iBiMED), Universidade de Aveiro, 3810-193 Aveiro, Portugal
| |
Collapse
|
5
|
Cyclin-dependent kinase 1-mediated phosphorylation of protein kinase N1 promotes anchorage-independent growth and migration. Cell Signal 2020; 69:109546. [PMID: 31981797 DOI: 10.1016/j.cellsig.2020.109546] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 01/17/2020] [Accepted: 01/21/2020] [Indexed: 12/30/2022]
Abstract
Protein kinase N1 (PKN1) is a member of the protein kinase C superfamily. Aberrations of PKN1 kinase activity are involved in several human pathological processes, including cancer. We found that PKN family proteins (PKN1/2/3) are phosphorylated in response to antitubulin drug-induced mitotic arrest. We identified cyclin-dependent kinase 1 (CDK1) as the corresponding kinase for PKN protein phosphorylation. CDK1 phosphorylates PKN1 at S533, S537, S562, and S916 in vitro and in cells during drug-induced mitotic arrest. Immunofluorescence staining further confirmed that PKN1 phosphorylation occurs during normal mitosis in a CDK1-dependent manner. Knockdown of PKN1 significantly inhibited anchorage-independent growth and migration without affecting proliferation in multiple cancer cell lines. We further showed that mitotic phosphorylation is essential for PKN1's oncogenic function, as the non-phosphorylatable mutant PKN1-4A failed to rescue anchorage-independent growth and migration in PKN1-knockdown cells. Thus, our findings reveal a novel regulatory mechanism for PKN1 in mitosis and its role in tumorigenesis.
Collapse
|
6
|
The Arp2/3 complex and the formin, Diaphanous, are both required to regulate the size of germline ring canals in the developing egg chamber. Dev Biol 2020; 461:75-85. [PMID: 31945342 DOI: 10.1016/j.ydbio.2020.01.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 01/10/2020] [Accepted: 01/10/2020] [Indexed: 01/30/2023]
Abstract
Intercellular bridges are an essential structural feature found in both germline and somatic cells throughout the animal kingdom. Because of their large size, the germline intercellular bridges, or ring canals, in the developing fruit fly egg chamber are an excellent model to study the formation, stabilization, and growth of these structures. Within the egg chamber, the germline ring canals connect 15 supporting nurse cells to the developing oocyte, facilitating the transfer of materials required for successful oogenesis. The ring canals are derived from a stalled actomyosin contractile ring; once formed, additional actin and actin-binding proteins are recruited to the ring to support the 20-fold growth that accompanies oogenesis. These behaviors provide a unique model system to study the actin regulators that control incomplete cytokinesis, intercellular bridge formation, and growth. By temporally controlling their expression in the germline, we have demonstrated that the Arp2/3 complex and the formin, Diaphanous (Dia), coordinately regulate ring canal size and growth throughout oogenesis. Dia is required for successful incomplete cytokinesis and the initial stabilization of the germline ring canals. Once ring canals have formed, the Arp2/3 complex and Dia cooperate to determine ring canal size and maintain stability. Our data suggest that nurse cells must maintain a precise balance between the activity of these two nucleators during oogenesis.
Collapse
|
7
|
Tsankova A, Pham TT, Garcia DS, Otte F, Cabernard C. Cell Polarity Regulates Biased Myosin Activity and Dynamics during Asymmetric Cell Division via Drosophila Rho Kinase and Protein Kinase N. Dev Cell 2017; 42:143-155.e5. [PMID: 28712722 DOI: 10.1016/j.devcel.2017.06.012] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 02/06/2017] [Accepted: 06/14/2017] [Indexed: 12/18/2022]
Abstract
Cell and tissue morphogenesis depends on the correct regulation of non-muscle Myosin II, but how this motor protein is spatiotemporally controlled is incompletely understood. Here, we show that in asymmetrically dividing Drosophila neural stem cells, cell intrinsic polarity cues provide spatial and temporal information to regulate biased Myosin activity. Using live cell imaging and a genetically encoded Myosin activity sensor, we found that Drosophila Rho kinase (Rok) enriches for activated Myosin on the neuroblast cortex prior to nuclear envelope breakdown (NEB). After NEB, the conserved polarity protein Partner of Inscuteable (Pins) sequentially enriches Rok and Protein Kinase N (Pkn) on the apical neuroblast cortex. Our data suggest that apical Rok first increases phospho-Myosin, followed by Pkn-mediated Myosin downregulation, possibly through Rok inhibition. We propose that polarity-induced spatiotemporal control of Rok and Pkn is important for unequal cortical expansion, ensuring correct cleavage furrow positioning and the establishment of physical asymmetry.
Collapse
Affiliation(s)
- Anna Tsankova
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, 4056 Basel, Switzerland
| | - Tri Thanh Pham
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, 4056 Basel, Switzerland; Department of Biology, University of Washington, 24 Kinkaid Hall, Seattle, WA 98105, USA
| | | | - Fabian Otte
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, 4056 Basel, Switzerland
| | - Clemens Cabernard
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, 4056 Basel, Switzerland; Department of Biology, University of Washington, 24 Kinkaid Hall, Seattle, WA 98105, USA.
| |
Collapse
|
8
|
Heissler SM, Chinthalapudi K, Sellers JR. Kinetic characterization of the sole nonmuscle myosin-2 from the model organism Drosophila melanogaster. FASEB J 2015; 29:1456-66. [PMID: 25636739 DOI: 10.1096/fj.14-266742] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Accepted: 12/01/2014] [Indexed: 12/31/2022]
Abstract
Nonmuscle myosin-2 is the primary enzyme complex powering contractility of the F-actin cytoskeleton in the model organism Drosophila. Despite myosin's essential function in fly development and homeostasis, its kinetic features remain elusive. The purpose of this in vitro study is a detailed steady-state and presteady-state kinetic characterization of the Drosophila nonmuscle myosin-2 motor domain. Kinetic features are a slow steady-state ATPase activity, high affinities for F-actin and ADP, and a low duty ratio. Comparative analysis of the overall enzymatic signatures across the nonmuscle myosin-2 complement from model organisms indicates that the Drosophila protein resembles nonmuscle myosin-2s from metazoa rather than protozoa, though modulatory aspects of myosin motor function are distinct. Drosophila nonmuscle myosin-2 is uniquely insensitive toward blebbistatin, a commonly used myosin-2 inhibitor. An in silico modeling approach together with kinetic studies indicate that the nonconsensus amino acid Met466 in the Drosophila nonmuscle myosin-2 active-site loop switch-2 acts as blebbistatin desensitizer. Introduction of the M466I mutation sensitized the protein for blebbistatin, resulting in a half-maximal inhibitory concentration of 36.3 ± 4.1 µM. Together, these data show that Drosophila nonmuscle myosin-2 is a bona fide molecular motor and establish an important link between switch-2 and blebbistatin sensitivity.
Collapse
Affiliation(s)
- Sarah M Heissler
- *Laboratory of Molecular Physiology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA; and The Cell Adhesion Laboratory, Department of Cancer Biology, The Scripps Research Institute, Jupiter, Florida, USA
| | - Krishna Chinthalapudi
- *Laboratory of Molecular Physiology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA; and The Cell Adhesion Laboratory, Department of Cancer Biology, The Scripps Research Institute, Jupiter, Florida, USA
| | - James R Sellers
- *Laboratory of Molecular Physiology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA; and The Cell Adhesion Laboratory, Department of Cancer Biology, The Scripps Research Institute, Jupiter, Florida, USA
| |
Collapse
|
9
|
Manning L, Starz-Gaiano M. Culturing Drosophila Egg Chambers and Investigating Developmental Processes Through Live Imaging. Methods Mol Biol 2015; 1328:73-88. [PMID: 26324430 DOI: 10.1007/978-1-4939-2851-4_5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Drosophila oogenesis provides many examples of essential processes in development. A myriad of genetic tools combined with recent advances in culturing egg chambers ex vivo has revealed several surprising mechanisms that govern how this tissue develops, and which could not have been determined in fixed tissues. Here we describe a straightforward protocol for dissecting ovaries, culturing egg chambers, and observing egg development in real time by fluorescent microscopy. This technique is suitable for observation of early- or late-stage egg development, and can be adapted to study a variety of cellular, molecular, or developmental processes. Ongoing analysis of oogenesis in living egg chambers has tremendous potential for discovery of new developmental mechanisms.
Collapse
Affiliation(s)
- Lathiena Manning
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD, 21250, USA
| | | |
Collapse
|