1
|
Vedelek V, Jankovics F, Zádori J, Sinka R. Mitochondrial Differentiation during Spermatogenesis: Lessons from Drosophila melanogaster. Int J Mol Sci 2024; 25:3980. [PMID: 38612789 PMCID: PMC11012351 DOI: 10.3390/ijms25073980] [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: 02/06/2024] [Revised: 03/22/2024] [Accepted: 03/28/2024] [Indexed: 04/14/2024] Open
Abstract
Numerous diseases can arise as a consequence of mitochondrial malfunction. Hence, there is a significant focus on studying the role of mitochondria in cancer, ageing, neurodegenerative diseases, and the field of developmental biology. Mitochondria could exist as discrete organelles in the cell; however, they have the ability to fuse, resulting in the formation of interconnected reticular structures. The dynamic changes between these forms correlate with mitochondrial function and mitochondrial health, and consequently, there is a significant scientific interest in uncovering the specific molecular constituents that govern these transitions. Moreover, the specialized mitochondria display a wide array of variable morphologies in their cristae formations. These inner mitochondrial structures are closely associated with the specific functions performed by the mitochondria. In multiple cases, the presence of mitochondrial dysfunction has been linked to male sterility, as it has been observed to cause a range of abnormal spermatogenesis and sperm phenotypes in different species. This review aims to elucidate the dynamic alterations and functions of mitochondria in germ cell development during the spermatogenesis of Drosophila melanogaster.
Collapse
Affiliation(s)
- Viktor Vedelek
- Department of Genetics, Faculty of Science and Informatics, University of Szeged, 6726 Szeged, Hungary
| | - Ferenc Jankovics
- Institute of Genetics, HUN-REN Biological Research Centre, 6726 Szeged, Hungary;
- Department of Medical Biology, Albert Szent-Györgyi Medical Centre, University of Szeged, 6720 Szeged, Hungary
| | - János Zádori
- Institute of Reproductive Medicine, Albert Szent-Györgyi Medical Centre, University of Szeged, 6723 Szeged, Hungary;
| | - Rita Sinka
- Department of Genetics, Faculty of Science and Informatics, University of Szeged, 6726 Szeged, Hungary
| |
Collapse
|
2
|
Vásquez-Limeta A, Lukasik K, Kong D, Sullenberger C, Luvsanjav D, Sahabandu N, Chari R, Loncarek J. CPAP insufficiency leads to incomplete centrioles that duplicate but fragment. J Cell Biol 2022; 221:213119. [PMID: 35404385 PMCID: PMC9007748 DOI: 10.1083/jcb.202108018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 01/13/2022] [Accepted: 02/28/2022] [Indexed: 11/22/2022] Open
Abstract
Centrioles are structures that assemble centrosomes. CPAP is critical for centrosome assembly, and its mutations are found in patients with diseases such as primary microcephaly. CPAP’s centrosomal localization, its dynamics, and the consequences of its insufficiency in human cells are poorly understood. Here we use human cells genetically engineered for fast degradation of CPAP, in combination with superresolution microscopy, to address these uncertainties. We show that three independent centrosomal CPAP populations are dynamically regulated during the cell cycle. We confirm that CPAP is critical for assembly of human centrioles, but not for recruitment of pericentriolar material on already assembled centrioles. Further, we reveal that CPAP insufficiency leads to centrioles with incomplete microtubule triplets that can convert to centrosomes, duplicate, and form mitotic spindle poles, but fragment owing to loss of cohesion between microtubule blades. These findings further our basic understanding of the role of CPAP in centrosome biogenesis and help understand how CPAP aberrations can lead to human diseases.
Collapse
Affiliation(s)
- Alejandra Vásquez-Limeta
- Laboratory of Protein Dynamics and Signaling, National Institutes of Health, National Cancer Institute, Center for Cancer Research, Frederick, MD
| | - Kimberly Lukasik
- Laboratory of Protein Dynamics and Signaling, National Institutes of Health, National Cancer Institute, Center for Cancer Research, Frederick, MD
| | - Dong Kong
- Laboratory of Protein Dynamics and Signaling, National Institutes of Health, National Cancer Institute, Center for Cancer Research, Frederick, MD
| | - Catherine Sullenberger
- Laboratory of Protein Dynamics and Signaling, National Institutes of Health, National Cancer Institute, Center for Cancer Research, Frederick, MD
| | - Delgermaa Luvsanjav
- Laboratory of Protein Dynamics and Signaling, National Institutes of Health, National Cancer Institute, Center for Cancer Research, Frederick, MD
| | - Natalie Sahabandu
- Laboratory of Protein Dynamics and Signaling, National Institutes of Health, National Cancer Institute, Center for Cancer Research, Frederick, MD
| | - Raj Chari
- Genome Modification Core, Laboratory Animal Sciences Program, Frederick National Laboratory for Cancer Research, Frederick, MD
| | - Jadranka Loncarek
- Laboratory of Protein Dynamics and Signaling, National Institutes of Health, National Cancer Institute, Center for Cancer Research, Frederick, MD
| |
Collapse
|
3
|
The Microtubule Cytoskeleton during the Early Drosophila Spermiogenesis. Cells 2020; 9:cells9122684. [PMID: 33327573 PMCID: PMC7765066 DOI: 10.3390/cells9122684] [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: 10/07/2020] [Revised: 11/29/2020] [Accepted: 12/12/2020] [Indexed: 12/19/2022] Open
Abstract
Sperm elongation and nuclear shaping in Drosophila largely depends on the microtubule cytoskeleton that in early spermatids has centrosomal and non-centrosomal origins. We report here an additional γ-tubulin focus localized on the anterior pole of the nucleus in correspondence of the apical end of the perinuclear microtubules that run within the dense complex. The perinuclear microtubules are nucleated by the pericentriolar material, or centriole adjunct, that surrounds the basal body and are retained to play a major role in nuclear shaping. However, we found that both the perinuclear microtubules and the dense complex are present in spermatids lacking centrioles. Therefore, the basal body or the centriole adjunct seem to be dispensable for the organization and assembly of these structures. These observations shed light on a novel localization of γ-tubulin and open a new scenario on the distribution of the microtubules and the organization of the dense complex during early Drosophila spermiogenesis.
Collapse
|
4
|
Galletta BJ, Ortega JM, Smith SL, Fagerstrom CJ, Fear JM, Mahadevaraju S, Oliver B, Rusan NM. Sperm Head-Tail Linkage Requires Restriction of Pericentriolar Material to the Proximal Centriole End. Dev Cell 2020; 53:86-101.e7. [PMID: 32169161 DOI: 10.1016/j.devcel.2020.02.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 11/22/2019] [Accepted: 02/07/2020] [Indexed: 01/27/2023]
Abstract
The centriole, or basal body, is the center of attachment between the sperm head and tail. While the distal end of the centriole templates the cilia, the proximal end associates with the nucleus. Using Drosophila, we identify a centriole-centric mechanism that ensures proper proximal end docking to the nucleus. This mechanism relies on the restriction of pericentrin-like protein (PLP) and the pericentriolar material (PCM) to the proximal end of the centriole. PLP is restricted proximally by limiting its mRNA and protein to the earliest stages of centriole elongation. Ectopic positioning of PLP to more distal portions of the centriole is sufficient to redistribute PCM and microtubules along the entire centriole length. This results in erroneous, lateral centriole docking to the nucleus, leading to spermatid decapitation as a result of a failure to form a stable head-tail linkage.
Collapse
Affiliation(s)
- Brian J Galletta
- Cell and Developmental Biology Center, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Jacob M Ortega
- Cell and Developmental Biology Center, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Samantha L Smith
- Cell and Developmental Biology Center, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Carey J Fagerstrom
- Cell and Developmental Biology Center, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Justin M Fear
- Developmental Genomics Section, Laboratory of Cell and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Sharvani Mahadevaraju
- Developmental Genomics Section, Laboratory of Cell and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Brian Oliver
- Developmental Genomics Section, Laboratory of Cell and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Nasser M Rusan
- Cell and Developmental Biology Center, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
| |
Collapse
|
5
|
Riparbelli MG, Persico V, Callaini G. A transient microtubule-based structure uncovers a new intrinsic asymmetry between the mother centrioles in the early Drosophila spermatocytes. Cytoskeleton (Hoboken) 2019; 75:472-480. [PMID: 30381895 DOI: 10.1002/cm.21503] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 09/27/2018] [Accepted: 10/25/2018] [Indexed: 12/23/2022]
Abstract
Parent centrioles are characterized in most organisms by individual morphological traits and have distinct asymmetries that provide different functional properties. By contrast, mother and daughter centrioles are morphologically undistinguishable during Drosophila male gametogenesis. Here we report the presence of previously unrecognized microtubule-based structures that extend into the peripheral cytoplasm of the Drosophila polar spermatocytes at the onset of the first meiosis and are positive for the typical centriolar protein Sas-4 and for the kinesin-like protein Klp10A. These structures have a short lifespan and are no longer found in early apolar spermatocytes. Remarkably, each polar spermatocyte holds only one microtubule-based structure that is associated with one of the sister centriole pairs and specifically with the mother centriole. These findings reveal an inherent asymmetry between the parent centrioles at the onset of male meiosis and also uncover unexpected functional properties between the mother centrioles of the same cells.
Collapse
|
6
|
Avidor-Reiss T, Mazur M, Fishman EL, Sindhwani P. The Role of Sperm Centrioles in Human Reproduction - The Known and the Unknown. Front Cell Dev Biol 2019; 7:188. [PMID: 31632960 PMCID: PMC6781795 DOI: 10.3389/fcell.2019.00188] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 08/23/2019] [Indexed: 01/02/2023] Open
Abstract
Each human spermatozoon contains two remodeled centrioles that it contributes to the zygote. There, the centrioles reconstitute a centrosome that assembles the sperm aster and participate in pronuclei migration and cleavage. Thus, centriole abnormalities may be a cause of male factor infertility and failure to carry pregnancy to term. However, the precise mechanisms by which sperm centrioles contribute to embryonic development in humans are still unclear, making the search for a link between centriole abnormalities and impaired male fecundity particularly difficult. Most previous investigations into the role of mammalian centrioles during fertilization have been completed in murine models; however, because mouse sperm and zygotes appear to lack centrioles, these studies provide information that is limited in its applicability to humans. Here, we review studies that examine the role of the sperm centrioles in the early embryo, with particular emphasis on humans. Available literature includes case studies and case-control studies, with a few retrospective studies and no prospective studies reported. This literature has provided some insight into the morphological characteristics of sperm centrioles in the zygote and has allowed identification of some centriole abnormalities in rare cases. Many of these studies suggest centriole involvement in early embryogenesis based on phenotypes of the embryo with only indirect evidence for centriole abnormality. Overall, these studies suggest that centriole abnormalities are present in some cases of sperm with asthenoteratozoospermia and unexplained infertility. Yet, most previously published studies have been restricted by the laborious techniques (like electron microscopy) and the limited availability of centriolar markers, resulting in small-scale studies and the lack of solid causational evidence. With recent progress in sperm centriole biology, such as the identification of the unique composition of sperm centrioles and the discovery of the atypical centriole, it is now possible to begin to fill the gaps in sperm centriole epidemiology and to identify the etiology of sperm centriole dysfunction in humans.
Collapse
Affiliation(s)
- Tomer Avidor-Reiss
- Department of Biological Sciences, College of Natural Sciences and Mathematics, The University of Toledo, Toledo, OH, United States.,Department of Urology, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, United States
| | - Matthew Mazur
- Department of Biological Sciences, College of Natural Sciences and Mathematics, The University of Toledo, Toledo, OH, United States.,Department of Urology, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, United States
| | - Emily L Fishman
- Department of Biological Sciences, College of Natural Sciences and Mathematics, The University of Toledo, Toledo, OH, United States
| | - Puneet Sindhwani
- Department of Biological Sciences, College of Natural Sciences and Mathematics, The University of Toledo, Toledo, OH, United States.,Department of Urology, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, United States
| |
Collapse
|
7
|
Gambarotto D, Pennetier C, Ryniawec JM, Buster DW, Gogendeau D, Goupil A, Nano M, Simon A, Blanc D, Racine V, Kimata Y, Rogers GC, Basto R. Plk4 Regulates Centriole Asymmetry and Spindle Orientation in Neural Stem Cells. Dev Cell 2019; 50:11-24.e10. [PMID: 31130353 PMCID: PMC6614718 DOI: 10.1016/j.devcel.2019.04.036] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 03/08/2019] [Accepted: 04/23/2019] [Indexed: 02/06/2023]
Abstract
Defects in mitotic spindle orientation (MSO) disrupt the organization of stem cell niches impacting tissue morphogenesis and homeostasis. Mutations in centrosome genes reduce MSO fidelity, leading to tissue dysplasia and causing several diseases such as microcephaly, dwarfism, and cancer. Whether these mutations perturb spindle orientation solely by affecting astral microtubule nucleation or whether centrosome proteins have more direct functions in regulating MSO is unknown. To investigate this question, we analyzed the consequences of deregulating Plk4 (the master centriole duplication kinase) activity in Drosophila asymmetrically dividing neural stem cells. We found that Plk4 functions upstream of MSO control, orchestrating centriole symmetry breaking and consequently centrosome positioning. Mechanistically, we show that Plk4 acts through Spd2 phosphorylation, which induces centriole release from the apical cortex. Overall, this work not only reveals a role for Plk4 in regulating centrosome function but also links the centrosome biogenesis machinery with the MSO apparatus. Drosophila Plk4 mutant NSCs show defects in centriole asymmetry and spindle positioning Apical centriole anchoring requires the PCM protein Spd-2 and the APC/C activator Fzr Movement of the centriole toward the basal side of the cell requires Plk4 activity At the mother centriole, Plk4 phosphorylates Spd2 to trigger PCM shedding and Fzr loss
Collapse
Affiliation(s)
- Davide Gambarotto
- Institut Curie, PSL Research University, CNRS, UMR144, Biology of centrosomes and Genetic instability lab, Paris 75005, France
| | - Carole Pennetier
- Institut Curie, PSL Research University, CNRS, UMR144, Biology of centrosomes and Genetic instability lab, Paris 75005, France
| | - John M Ryniawec
- Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, University of Arizona, Tucson, AZ 85724, USA
| | - Daniel W Buster
- Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, University of Arizona, Tucson, AZ 85724, USA
| | - Delphine Gogendeau
- Institut Curie, PSL Research University, CNRS, UMR144, Biology of centrosomes and Genetic instability lab, Paris 75005, France
| | - Alix Goupil
- Institut Curie, PSL Research University, CNRS, UMR144, Biology of centrosomes and Genetic instability lab, Paris 75005, France
| | - Maddalena Nano
- Institut Curie, PSL Research University, CNRS, UMR144, Biology of centrosomes and Genetic instability lab, Paris 75005, France
| | - Anthony Simon
- Institut Curie, PSL Research University, CNRS, UMR144, Biology of centrosomes and Genetic instability lab, Paris 75005, France
| | - Damien Blanc
- QuantaCell, 2 Allée du Doyen Georges Brus, Pessac 33600, France
| | - Victor Racine
- QuantaCell, 2 Allée du Doyen Georges Brus, Pessac 33600, France
| | - Yuu Kimata
- School of Life Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Pudong, Shanghai, 201210, China
| | - Gregory C Rogers
- Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, University of Arizona, Tucson, AZ 85724, USA.
| | - Renata Basto
- Institut Curie, PSL Research University, CNRS, UMR144, Biology of centrosomes and Genetic instability lab, Paris 75005, France.
| |
Collapse
|
8
|
Tillery MML, Blake-Hedges C, Zheng Y, Buchwalter RA, Megraw TL. Centrosomal and Non-Centrosomal Microtubule-Organizing Centers (MTOCs) in Drosophila melanogaster. Cells 2018; 7:E121. [PMID: 30154378 PMCID: PMC6162459 DOI: 10.3390/cells7090121] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 08/19/2018] [Accepted: 08/20/2018] [Indexed: 12/14/2022] Open
Abstract
The centrosome is the best-understood microtubule-organizing center (MTOC) and is essential in particular cell types and at specific stages during Drosophila development. The centrosome is not required zygotically for mitosis or to achieve full animal development. Nevertheless, centrosomes are essential maternally during cleavage cycles in the early embryo, for male meiotic divisions, for efficient division of epithelial cells in the imaginal wing disc, and for cilium/flagellum assembly in sensory neurons and spermatozoa. Importantly, asymmetric and polarized division of stem cells is regulated by centrosomes and by the asymmetric regulation of their microtubule (MT) assembly activity. More recently, the components and functions of a variety of non-centrosomal microtubule-organizing centers (ncMTOCs) have begun to be elucidated. Throughout Drosophila development, a wide variety of unique ncMTOCs form in epithelial and non-epithelial cell types at an assortment of subcellular locations. Some of these cell types also utilize the centrosomal MTOC, while others rely exclusively on ncMTOCs. The impressive variety of ncMTOCs being discovered provides novel insight into the diverse functions of MTOCs in cells and tissues. This review highlights our current knowledge of the composition, assembly, and functional roles of centrosomal and non-centrosomal MTOCs in Drosophila.
Collapse
Affiliation(s)
- Marisa M L Tillery
- Department of Biomedical Sciences, Florida State University, 1115 West Call St., Tallahassee, FL 32306, USA.
| | - Caitlyn Blake-Hedges
- Department of Biomedical Sciences, Florida State University, 1115 West Call St., Tallahassee, FL 32306, USA.
| | - Yiming Zheng
- Department of Biomedical Sciences, Florida State University, 1115 West Call St., Tallahassee, FL 32306, USA.
| | - Rebecca A Buchwalter
- Department of Biomedical Sciences, Florida State University, 1115 West Call St., Tallahassee, FL 32306, USA.
| | - Timothy L Megraw
- Department of Biomedical Sciences, Florida State University, 1115 West Call St., Tallahassee, FL 32306, USA.
| |
Collapse
|
9
|
Reina J, Gottardo M, Riparbelli MG, Llamazares S, Callaini G, Gonzalez C. Centrobin is essential for C-tubule assembly and flagellum development in Drosophila melanogaster spermatogenesis. J Cell Biol 2018; 217:2365-2372. [PMID: 29712734 PMCID: PMC6028543 DOI: 10.1083/jcb.201801032] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Revised: 04/16/2018] [Accepted: 04/24/2018] [Indexed: 12/15/2022] Open
Abstract
This work shows that Centrobin (CNB) mutant males assemble aberrant basal bodies and do not produce functional sperm. It also shows that CNB can act as a positive or negative regulator of ciliogenesis in a cell type–dependent manner. Centrobin homologues identified in different species localize on daughter centrioles. In Drosophila melanogaster sensory neurons, Centrobin (referred to as CNB in Drosophila) inhibits basal body function. These data open the question of CNB’s role in spermatocytes, where daughter and mother centrioles become basal bodies. In this study, we report that in these cells, CNB localizes equally to mother and daughter centrioles and is essential for C-tubules to attain the right position and remain attached to B-tubules as well as for centrioles to grow in length. CNB appears to be dispensable for meiosis, but flagellum development is severely compromised in Cnb mutant males. Remarkably, three N-terminal POLO phosphorylation sites that are critical for CNB function in neuroblasts are dispensable for spermatogenesis. Our results underpin the multifunctional nature of CNB that plays different roles in different cell types in Drosophila, and they identify CNB as an essential component for C-tubule assembly and flagellum development in Drosophila spermatogenesis.
Collapse
Affiliation(s)
- Jose Reina
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Marco Gottardo
- Department of Life Sciences, University of Siena, Siena, Italy
| | | | - Salud Llamazares
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | | | - Cayetano Gonzalez
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain .,Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain
| |
Collapse
|
10
|
Roque H, Saurya S, Pratt MB, Johnson E, Raff JW. Drosophila PLP assembles pericentriolar clouds that promote centriole stability, cohesion and MT nucleation. PLoS Genet 2018; 14:e1007198. [PMID: 29425198 PMCID: PMC5823460 DOI: 10.1371/journal.pgen.1007198] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 02/22/2018] [Accepted: 01/12/2018] [Indexed: 12/31/2022] Open
Abstract
Pericentrin is a conserved centrosomal protein whose dysfunction has been linked to several human diseases. It has been implicated in many aspects of centrosome and cilia function, but its precise role is unclear. Here, we examine Drosophila Pericentrin-like-protein (PLP) function in vivo in tissues that form both centrosomes and cilia. Plp mutant centrioles exhibit four major defects: (1) They are short and have subtle structural abnormalities; (2) They disengage prematurely, and so overduplicate; (3) They organise fewer cytoplasmic MTs during interphase; (4) When forming cilia, they fail to establish and/or maintain a proper connection to the plasma membrane—although, surprisingly, they can still form an axoneme-like structure that can recruit transition zone (TZ) proteins. We show that PLP helps assemble “pericentriolar clouds” of electron-dense material that emanate from the central cartwheel spokes and spread outward to surround the mother centriole. We propose that the partial loss of these structures may largely explain the complex centriole, centrosome and cilium defects we observe in Plp mutant cells. Centrioles are complex, microtubule (MT) based structures that organise two important cell organelles, the centrosome and the cilium. The centrosome is a major MT organising centre in many cell types, while the cilium functions as a cellular “antenna” responsible for regulating several cellular signalling pathways. Pericentrin is conserved centriole-binding protein that plays an important part in centrosome and cilium function, and mutations in the Pericentrin gene are linked to several human diseases. Here we use the fruit-fly Drosophila melanogaster to investigate how Pericentrin-Like-Protein (the fly homolog of Pericentrin) contributes to centriole, centrosome and cilium function. We find that Plp mutant fly centrioles have subtle structural defects, organize less microtubules, and do not properly migrate to the cell membrane to form cilia. We also observe that PLP helps assemble “pericentriolar clouds”—dense structures that emanate from the centriole, and appear to interact with microtubules, as well as connect existing centrioles to newly formed ones. In mutant flies these structures are significantly reduced in size. We propose that the defects in these PLP structures can explain most, if not all, the complex defects observed in Plp mutants.
Collapse
Affiliation(s)
- Helio Roque
- The Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, United Kingdom
| | - Saroj Saurya
- The Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, United Kingdom
| | - Metta B. Pratt
- The Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, United Kingdom
| | - Errin Johnson
- The Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, United Kingdom
| | - Jordan W. Raff
- The Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, United Kingdom
- * E-mail:
| |
Collapse
|
11
|
Riparbelli MG, Gottardo M, Callaini G. Parthenogenesis in Insects: The Centriole Renaissance. Results Probl Cell Differ 2017; 63:435-479. [PMID: 28779329 DOI: 10.1007/978-3-319-60855-6_19] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Building a new organism usually requires the contribution of two differently shaped haploid cells, the male and female gametes, each providing its genetic material to restore diploidy of the new born zygote. The successful execution of this process requires defined sequential steps that must be completed in space and time. Otherwise, development fails. Relevant among the earlier steps are pronuclear migration and formation of the first mitotic spindle that promote the mixing of parental chromosomes and the formation of the zygotic nucleus. A complex microtubule network ensures the proper execution of these processes. Instrumental to microtubule organization and bipolar spindle assembly is a distinct non-membranous organelle, the centrosome. Centrosome inheritance during fertilization is biparental, since both gametes provide essential components to build a functional centrosome. This model does not explain, however, centrosome formation during parthenogenetic development, a special mode of sexual reproduction in which the unfertilized egg develops without the contribution of the male gamete. Moreover, whereas fertilization is a relevant example in which the cells actively check the presence of only one centrosome, to avoid multipolar spindle formation, the development of parthenogenetic eggs is ensured, at least in insects, by the de novo assembly of multiple centrosomes.Here, we will focus our attention on the assembly of functional centrosomes following fertilization and during parthenogenetic development in insects. Parthenogenetic development in which unfertilized eggs are naturally depleted of centrosomes would provide a useful experimental system to investigate centriole assembly and duplication together with centrosome formation and maturation.
Collapse
Affiliation(s)
| | - Marco Gottardo
- Department of Life Sciences, University of Siena, Via A. Moro 2, 53100, Siena, Italy
| | - Giuliano Callaini
- Department of Life Sciences, University of Siena, Via A. Moro 2, 53100, Siena, Italy.
| |
Collapse
|
12
|
Nano M, Basto R. Consequences of Centrosome Dysfunction During Brain Development. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1002:19-45. [PMID: 28600781 DOI: 10.1007/978-3-319-57127-0_2] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Development requires cell proliferation, differentiation and spatial organization of daughter cells to occur in a highly controlled manner. The mode of cell division, the extent of proliferation and the spatial distribution of mitosis allow the formation of tissues of the right size and with the correct structural organization. All these aspects depend on cell cycle duration, correct chromosome segregation and spindle orientation. The centrosome, which is the main microtubule-organizing centre (MTOC) of animal cells, contributes to all these processes. As one of the most structurally complex organs in our body, the brain is particularly susceptible to centrosome dysfunction. Autosomal recessive primary microcephaly (MCPH), primordial dwarfism disease Seckel syndrome (SCKS) and microcephalic osteodysplastic primordial dwarfism type II (MOPD-II) are often connected to mutations in centrosomal genes. In this chapter, we discuss the consequences of centrosome dysfunction during development and how they can contribute to the etiology of human diseases.
Collapse
Affiliation(s)
- Maddalena Nano
- Institut Curie, PSL Research University, CNRS UMR144, 12 rue Lhomond, 75005, Paris, France
| | - Renata Basto
- Institut Curie, PSL Research University, CNRS UMR144, 12 rue Lhomond, 75005, Paris, France.
| |
Collapse
|
13
|
Gottardo M, Callaini G, Riparbelli MG. Klp10A modulates the localization of centriole-associated proteins during Drosophila male gametogenesis. Cell Cycle 2016; 15:3432-3441. [PMID: 27764551 DOI: 10.1080/15384101.2016.1248005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Mutations in Klp10A, a microtubule-depolymerising Kinesin-13, lead to overly long centrioles in Drosophila male germ cells. We demonstrated that the loss of Klp10A modifies the distribution of typical proteins involved in centriole assembly and function. In the absence of Klp10A the distribution of Drosophila pericentrin-like protein (Dplp), Sas-4 and Sak/Plk4 that are restricted in control testes to the proximal end of the centriole increase along the centriole length. Remarkably, the cartwheel is lacking or it appears abnormal in mutant centrioles, suggesting that this structure may spatially delimit protein localization. Moreover, the parent centrioles that in control cells have the same dimensions grow at different rates in mutant testes with the mother centrioles longer than the daughters. Daughter centrioles have often an ectopic position with respect to the proximal end of the mothers and failed to recruit Dplp.
Collapse
Affiliation(s)
- Marco Gottardo
- a Department of Life Sciences , University of Siena , Siena , Italy
| | | | | |
Collapse
|
14
|
Abstract
The centrosome is the main microtubule organizing center of animal cells. It contributes to spindle assembly and orientation during mitosis and to ciliogenesis in interphase. Numerical and structural defects in this organelle are known to be associated with developmental disorders such as dwarfism and microcephaly, but only recently, the molecular mechanisms linking centrosome aberrations to altered physiology are being elucidated. Defects in centrosome number or structure have also been described in cancer. These opposite clinical outcomes--arising from reduced proliferation and overproliferation respectively--can be explained in light of the tissue- and developmental-specific requirements for centrosome functions. The pathological outcomes of centrosome deficiencies have become clearer when considering its consequences. Among them, there are genetic instability (mainly aneuploidy, a defect in chromosome number), defects in the symmetry of cell division (important for cell fate specification and tissue architecture) and impaired ciliogenesis. In this review, we discuss the origins and the consequences of centrosome flaws, with particular attention on how they contribute to developmental diseases.
Collapse
Affiliation(s)
- Maddalena Nano
- Institut Curie, PSL Research University, CNRS UMR144, 12 rue Lhomond, 75005, Paris, France
| | - Renata Basto
- Institut Curie, PSL Research University, CNRS UMR144, 12 rue Lhomond, 75005, Paris, France.
| |
Collapse
|
15
|
Gottardo M, Callaini G, Riparbelli MG. Does Unc-GFP uncover ciliary structures in the rhabdomeric eye of Drosophila? J Cell Sci 2016; 129:2726-31. [PMID: 27235419 DOI: 10.1242/jcs.185942] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 05/25/2016] [Indexed: 11/20/2022] Open
Abstract
The uncoordinated (unc) gene product, a potential ortholog of mammalian orofaciodigital syndrome 1 (Ofd1), is involved in the assembly of the ciliary axoneme in Drosophila and it is, therefore, constrained to cell types that have ciliary structures, namely type 1 sensory neurons and male germ cells. Here, we show that evenly spaced Unc-GFP spots are present in the eye imaginal discs of third-instar larvae. These spots are restricted to the R8 photoreceptor cell of each ommatidium in association with mother centrioles. This finding is unexpected because the Drosophila eye is of the rhabdomeric type and would be expected to lack ciliary structures.
Collapse
Affiliation(s)
- Marco Gottardo
- University of Siena, Department of Life Sciences, Via A. Moro 2, 53100 Siena, Italy
| | - Giuliano Callaini
- University of Siena, Department of Life Sciences, Via A. Moro 2, 53100 Siena, Italy
| | | |
Collapse
|
16
|
Galletta BJ, Jacobs KC, Fagerstrom CJ, Rusan NM. Asterless is required for centriole length control and sperm development. J Cell Biol 2016; 213:435-50. [PMID: 27185836 PMCID: PMC4878089 DOI: 10.1083/jcb.201501120] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 04/19/2016] [Indexed: 12/18/2022] Open
Abstract
Loss of the centriole protein Asterless (Asl) prevents centriole duplication, which has limited the study of its function at centrioles. Here, Galletta et al. show that Asl controls centriole length and ensures proper basal body functions during spermatogenesis. Centrioles are the foundation of two organelles, centrosomes and cilia. Centriole numbers and functions are tightly controlled, and mutations in centriole proteins are linked to a variety of diseases, including microcephaly. Loss of the centriole protein Asterless (Asl), the Drosophila melanogaster orthologue of Cep152, prevents centriole duplication, which has limited the study of its nonduplication functions. Here, we identify populations of cells with Asl-free centrioles in developing Drosophila tissues, allowing us to assess its duplication-independent function. We show a role for Asl in controlling centriole length in germline and somatic tissue, functioning via the centriole protein Cep97. We also find that Asl is not essential for pericentriolar material recruitment or centrosome function in organizing mitotic spindles. Lastly, we show that Asl is required for proper basal body function and spermatid axoneme formation. Insights into the role of Asl/Cep152 beyond centriole duplication could help shed light on how Cep152 mutations lead to the development of microcephaly.
Collapse
Affiliation(s)
- Brian J Galletta
- Cell Biology and Physiology Center, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892
| | - Katherine C Jacobs
- Cell Biology and Physiology Center, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892
| | - Carey J Fagerstrom
- Cell Biology and Physiology Center, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892
| | - Nasser M Rusan
- Cell Biology and Physiology Center, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892
| |
Collapse
|
17
|
Conduit PT, Wainman A, Novak ZA, Weil TT, Raff JW. Re-examining the role of Drosophila Sas-4 in centrosome assembly using two-colour-3D-SIM FRAP. eLife 2015; 4. [PMID: 26530814 PMCID: PMC4631861 DOI: 10.7554/elife.08483] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 10/01/2015] [Indexed: 01/10/2023] Open
Abstract
Centrosomes have many important functions and comprise a ‘mother’ and ‘daughter’ centriole surrounded by pericentriolar material (PCM). The mother centriole recruits and organises the PCM and templates the formation of the daughter centriole. It has been reported that several important Drosophila PCM-organising proteins are recruited to centrioles from the cytosol as part of large cytoplasmic ‘S-CAP’ complexes that contain the centriole protein Sas-4. In a previous paper (Conduit et al., 2014b) we showed that one of these proteins, Cnn, and another key PCM-organising protein, Spd-2, are recruited around the mother centriole before spreading outwards to form a scaffold that supports mitotic PCM assembly; the recruitment of Cnn and Spd-2 is dependent on another S-CAP protein, Asl. We show here, however, that Cnn, Spd-2 and Asl are not recruited to the mother centriole as part of a complex with Sas-4. Thus, PCM recruitment in fly embryos does not appear to require cytosolic S-CAP complexes. DOI:http://dx.doi.org/10.7554/eLife.08483.001
Collapse
Affiliation(s)
- Paul T Conduit
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom.,Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Alan Wainman
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Zsofia A Novak
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Timothy T Weil
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Jordan W Raff
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
18
|
Abstract
It has become clear that the role of centrosomes extends well beyond that of important microtubule organizers. There is increasing evidence that they also function as coordination centres in eukaryotic cells, at which specific cytoplasmic proteins interact at high concentrations and important cell decisions are made. Accordingly, hundreds of proteins are concentrated at centrosomes, including cell cycle regulators, checkpoint proteins and signalling molecules. Nevertheless, several observations have raised the question of whether centrosomes are essential for many cell processes. Recent findings have shed light on the functions of centrosomes in animal cells and on the molecular mechanisms of centrosome assembly, in particular during mitosis. These advances should ultimately allow the in vitro reconstitution of functional centrosomes from their component proteins to unlock the secrets of these enigmatic organelles.
Collapse
|
19
|
Abstract
Stem cells are necessary for the maintenance of many adult tissues. Signals within the stem cell microenvironment, or niche, regulate the self-renewal and differentiation capability of these cells. Misregulation of these signals through mutation or damage can lead to overgrowth or depletion of different stem cell pools. In this review, we focus on the Drosophila testis and ovary, both of which contain well-defined niches, as well as the mouse testis, which has become a more approachable stem cell system with recent technical advances. We discuss the signals that regulate gonadal stem cells in their niches, how these signals mediate self-renewal and differentiation under homeostatic conditions, and how stress, whether from mutations or damage, can cause changes in cell fate and drive stem cell competition.
Collapse
Affiliation(s)
- Leah Joy Greenspan
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205; , ,
| | - Margaret de Cuevas
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205; , ,
| | - Erika Matunis
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205; , ,
| |
Collapse
|
20
|
Bang C, Cheng J. Dynamic interplay of spectrosome and centrosome organelles in asymmetric stem cell divisions. PLoS One 2015; 10:e0123294. [PMID: 25849996 PMCID: PMC4388834 DOI: 10.1371/journal.pone.0123294] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 02/16/2015] [Indexed: 12/20/2022] Open
Abstract
Stem cells have remarkable self-renewal ability and differentiation potency, which are critical for tissue repair and tissue homeostasis. Recently it has been found, in many systems (e.g. gut, neurons, and hematopoietic stem cells), that the self-renewal and differentiation balance is maintained when the stem cells divide asymmetrically. Drosophila male germline stem cells (GSCs), one of the best characterized model systems with well-defined stem cell niches, were reported to divide asymmetrically, where centrosome plays an important role. Utilizing time-lapse live cell imaging, customized tracking, and image processing programs, we found that most acentrosomal GSCs have the spectrosomes reposition from the basal end (wild type) to the apical end close to hub-GSC interface (acentrosomal GSCs). In addition, these apically positioned spectrosomes were mostly stationary while the basally positioned spectrosomes were mobile. For acentrosomal GSCs, their mitotic spindles were still highly oriented and divided asymmetrically with longer mitosis duration, resulting in asymmetric divisions. Moreover, when the spectrosome was knocked out, the centrosomes velocity decreased and centrosomes located closer to hub-GSC interface. We propose that in male GSCs, the spectrosome recruited to the apical end plays a complimentary role in ensuring proper spindle orientation when centrosome function is compromised.
Collapse
Affiliation(s)
- Chi Bang
- Department of Bioengineering, The University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Jun Cheng
- Department of Bioengineering, The University of Illinois at Chicago, Chicago, Illinois, United States of America
- * E-mail:
| |
Collapse
|
21
|
Mendes Maia T, Gogendeau D, Pennetier C, Janke C, Basto R. Bug22 influences cilium morphology and the post-translational modification of ciliary microtubules. Biol Open 2014; 3:138-51. [PMID: 24414207 PMCID: PMC3925317 DOI: 10.1242/bio.20146577] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Cilia and flagella are organelles essential for motility and sensing of environmental stimuli. Depending on the cell type, cilia acquire a defined set of functions and, accordingly, are built with an appropriate length and molecular composition. Several ciliary proteins display a high degree of conservation throughout evolution and mutations in ciliary genes are associated with various diseases such as ciliopathies and infertility. Here, we describe the role of the highly conserved ciliary protein, Bug22, in Drosophila. Previous studies in unicellular organisms have shown that Bug22 is required for proper cilia function, but its exact role in ciliogenesis has not been investigated yet. Null Bug22 mutant flies display cilia-associated phenotypes and nervous system defects. Furthermore, sperm differentiation is blocked at the individualization stage, due to impaired migration of the individualization machinery. Tubulin post-translational modifications (PTMs) such as polyglycylation, polyglutamylation or acetylation, are determinants of microtubule (MT) functions and stability in centrioles, cilia and neurons. We found defects in the timely incorporation of polyglycylation in sperm axonemal MTs of Bug22 mutants. In addition, we found that depletion of human Bug22 in RPE1 cells resulted in the appearance of longer cilia and reduced axonemal polyglutamylation. Our work identifies Bug22 as a protein that plays a conserved role in the regulation of PTMs of the ciliary axoneme.
Collapse
|
22
|
Fu J, Glover DM. Structured illumination of the interface between centriole and peri-centriolar material. Open Biol 2013; 2:120104. [PMID: 22977736 PMCID: PMC3438536 DOI: 10.1098/rsob.120104] [Citation(s) in RCA: 186] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Accepted: 08/02/2012] [Indexed: 12/22/2022] Open
Abstract
The increase in centrosome size in mitosis was described over a century ago, and yet it is poorly understood how centrioles, which lie at the core of centrosomes, organize the pericentriolar material (PCM) in this process. Now, structured illumination microscopy reveals in Drosophila that, before clouds of PCM appear, its proteins are closely associated with interphase centrioles in two tube-like layers: an inner layer occupied by centriolar microtubules, Sas-4, Spd-2 and Polo kinase; and an outer layer comprising Pericentrin-like protein (Dplp), Asterless (Asl) and Plk4 kinase. Centrosomin (Cnn) and γ-tubulin associate with this outer tube in G2 cells and, upon mitotic entry, Polo activity is required to recruit them together with Spd-2 into PCM clouds. Cnn is required for Spd-2 to expand into the PCM during this maturation process but can itself contribute to PCM independently of Spd-2. By contrast, the centrioles of spermatocytes elongate from a pre-existing proximal unit during the G2 preceding meiosis. Sas-4 is restricted to the microtubule-associated, inner cylinder and Dplp and Cnn to the outer cylinder of this proximal part. γ-Tubulin and Asl associate with the outer cylinder and Spd-2 with the inner cylinder throughout the entire G2 centriole. Although they occupy different spatial compartments on the G2 centriole, Cnn, Spd-2 and γ-tubulin become diminished at the centriole upon entry into meiosis to become part of PCM clouds.
Collapse
Affiliation(s)
- Jingyan Fu
- Cancer Research UK Cell Cycle Genetics Group, Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK.
| | | |
Collapse
|
23
|
Riparbelli MG, Callaini G, Megraw TL. Assembly and persistence of primary cilia in dividing Drosophila spermatocytes. Dev Cell 2012; 23:425-32. [PMID: 22898783 DOI: 10.1016/j.devcel.2012.05.024] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2011] [Revised: 04/16/2012] [Accepted: 05/29/2012] [Indexed: 10/28/2022]
Abstract
Basal bodies are freed from cilia and transition into centrioles to organize centrosomes in dividing cells. A mutually exclusive centriole/basal body existence during cell-cycle progression has become a widely accepted principle. Contrary to this view, we show here that cilia assemble and persist through two meiotic divisions in Drosophila spermatocytes. Remarkably, all four centrioles assemble primary cilia-centriole complexes that transit from the plasma membrane encased in a packet of membrane, recruit centrosomal material into microtubule-organizing centers, and persist at the spindle poles through division. Thus, spermatocyte centrioles organize centrosomes and cilia simultaneously at cell division. These findings challenge the prevailing view that cilia antagonize cell-cycle progression and raise the possibility that cilium retention at cell division may occur in diverse organisms and cell types.
Collapse
|
24
|
Matunis EL, Stine RR, de Cuevas M. Recent advances in Drosophila male germline stem cell biology. SPERMATOGENESIS 2012; 2:137-144. [PMID: 23087833 PMCID: PMC3469437 DOI: 10.4161/spmg.21763] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The ability of stem cells to divide asymmetrically to produce both self-renewing and differentiating daughter cells sustains many adult tissues, but germline stem cells (GSCs) are unique among stem cells as they perpetuate the genome of the species. The cellular and molecular mechanisms regulating most mammalian stem cells in their endogenous local microenvironments, or niches, are quite challenging to study. However, studies of stem cell niches such as those found in the Drosophila gonads have proven very useful. In these tissues, GSCs are housed in a readily identifiable niche, and the ability to genetically manipulate these cells and their neighbors has uncovered several fundamental mechanisms that are relevant to stem cells more generally. Here, we summarize recent work on the regulation of GSCs in the Drosophila testis niche by intercellular signals, and on the intracellular mechanisms that cooperate with these signals to ensure the survival of the germline. This review focuses on GSCs within the adult Drosophila testis; somatic stem cells in this tissue are reviewed by Zoller and Schulz in this issue.(1) For a review of the testis niche as a whole, see de Cuevas and Matunis,(2) and for more comprehensive reviews of the Drosophila testis, refer to Fuller(3) and Davies and Fuller.(4).
Collapse
Affiliation(s)
- Erika L. Matunis
- Department of Cell Biology; Johns Hopkins University School of Medicine; Baltimore, MD USA
| | - Rachel R. Stine
- Department of Cell Biology; Johns Hopkins University School of Medicine; Baltimore, MD USA
| | - Margaret de Cuevas
- Department of Cell Biology; Johns Hopkins University School of Medicine; Baltimore, MD USA
| |
Collapse
|
25
|
Enjolras C, Thomas J, Chhin B, Cortier E, Duteyrat JL, Soulavie F, Kernan MJ, Laurençon A, Durand B. Drosophila chibby is required for basal body formation and ciliogenesis but not for Wg signaling. ACTA ACUST UNITED AC 2012; 197:313-25. [PMID: 22508513 PMCID: PMC3328381 DOI: 10.1083/jcb.201109148] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In contrast to vertebrate CBY, which functions in WNT signaling, Drosophila CBY is essential for normal basal body structure and function but dispensable for Wg signaling. Centriole-to–basal body conversion, a complex process essential for ciliogenesis, involves the progressive addition of specific proteins to centrioles. CHIBBY (CBY) is a coiled-coil domain protein first described as interacting with β-catenin and involved in Wg-Int (WNT) signaling. We found that, in Drosophila melanogaster, CBY was exclusively expressed in cells that require functional basal bodies, i.e., sensory neurons and male germ cells. CBY was associated with the basal body transition zone (TZ) in these two cell types. Inactivation of cby led to defects in sensory transduction and in spermatogenesis. Loss of CBY resulted in altered ciliary trafficking into neuronal cilia, irregular deposition of proteins on spermatocyte basal bodies, and, consequently, distorted axonemal assembly. Importantly, cby1/1 flies did not show Wingless signaling defects. Hence, CBY is essential for normal basal body structure and function in Drosophila, potentially through effects on the TZ. The function of CBY in WNT signaling in vertebrates has either been acquired during vertebrate evolution or lost in Drosophila.
Collapse
Affiliation(s)
- Camille Enjolras
- Centre de Génétique et de Physiologie Moléculaire et Cellulaire, Centre National de la Recherche Scientifique UMR 5534, Université Claude Bernard Lyon 1, Villeurbanne, Lyon F69622, France
| | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Li S, Fernandez JJ, Marshall WF, Agard DA. Three-dimensional structure of basal body triplet revealed by electron cryo-tomography. EMBO J 2011; 31:552-62. [PMID: 22157822 PMCID: PMC3273388 DOI: 10.1038/emboj.2011.460] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2011] [Accepted: 11/15/2011] [Indexed: 12/03/2022] Open
Abstract
The basal body, derived from the centriole, is a microtubule-organizing organelle that nucleates the cilium in non-dividing cells. Cryo-electron tomography reveals the overall structure of this organelle, and provides insights its biogenesis and function. Basal bodies and centrioles play central roles in microtubule (MT)-organizing centres within many eukaryotes. They share a barrel-shaped cylindrical structure composed of nine MT triplet blades. Here, we report the structure of the basal body triplet at 33 Å resolution obtained by electron cryo-tomography and 3D subtomogram averaging. By fitting the atomic structure of tubulin into the EM density, we built a pseudo-atomic model of the tubulin protofilaments at the core of the triplet. The 3D density map reveals additional densities that represent non-tubulin proteins attached to the triplet, including a large inner circular structure in the basal body lumen, which functions as a scaffold to stabilize the entire basal body barrel. We found clear longitudinal structural variations along the basal body, suggesting a sequential and coordinated assembly mechanism. We propose a model in which δ-tubulin and other components participate in the assembly of the basal body.
Collapse
Affiliation(s)
- Sam Li
- The Howard Hughes Medical Institute, University of California, San Francisco, CA 94158-2517, USA
| | | | | | | |
Collapse
|
27
|
Yadlapalli S, Yamashita YM. Spindle positioning in the stem cell niche. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2011; 1:215-30. [DOI: 10.1002/wdev.16] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
28
|
Regulation of cyclin A localization downstream of Par-1 function is critical for the centrosome orientation checkpoint in Drosophila male germline stem cells. Dev Biol 2011; 361:57-67. [PMID: 22024320 DOI: 10.1016/j.ydbio.2011.10.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Revised: 10/03/2011] [Accepted: 10/04/2011] [Indexed: 12/12/2022]
Abstract
Male germline stem cells (GSCs) in Drosophila melanogaster divide asymmetrically by orienting the mitotic spindle with respect to the niche, a microenvironment that specifies stem cell identity. The spindle orientation is prepared during interphase through stereotypical positioning of the centrosomes. We recently demonstrated that GSCs possess a checkpoint ("the centrosome orientation checkpoint") that monitors correct centrosome orientation prior to mitosis to ensure an oriented spindle and thus asymmetric outcome of the division. Here, we show that Par-1, a serine/threonine kinase that regulates polarity in many systems, is involved in this checkpoint. Par-1 shows a cell cycle-dependent localization to the spectrosome, a germline-specific, endoplasmic reticulum-like organelle. Furthermore, the localization of cyclin A, which is normally localized to the spectrosome, is perturbed in par-1 mutant GSCs. Interestingly, overexpression of mutant cyclin A that does not localize to the spectrosome and mutation in hts, a core component of the spectrosome, both lead to defects in the centrosome orientation checkpoint. We propose that the regulation of cyclin A localization via Par-1 function plays a critical role in the centrosome orientation checkpoint.
Collapse
|
29
|
Abstract
In metazoans, tissue maintenance and regeneration depend on adult stem cells, which are characterized by their ability to self-renew and generate differentiating progeny in response to the needs of the tissues in which they reside. In the Drosophila testis, germline and somatic stem cells are housed together in a common niche, where they are regulated by local signals, epigenetic mechanisms and systemic factors. These stem cell populations in the Drosophila testis have the unique advantage of being easy to identify and manipulate, and hence much progress has been made in understanding how this niche operates. Here, we summarize recent work on stem cells in the adult Drosophila testis and discuss the remarkable ability of these stem cells to respond to change within the niche.
Collapse
Affiliation(s)
- Margaret de Cuevas
- Department of Cell Biology, Johns Hopkins School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205, USA.
| | | |
Collapse
|
30
|
Fly meets yeast: checking the correct orientation of cell division. Trends Cell Biol 2011; 21:526-33. [PMID: 21705221 DOI: 10.1016/j.tcb.2011.05.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Revised: 05/18/2011] [Accepted: 05/24/2011] [Indexed: 12/13/2022]
Abstract
Cell division is generally thought to be a process that produces an exact copy of the mother cell by precisely replicating its genomic DNA, doubling organelles, and segregating them into two cells. Many cell types from bacteria to human cells divide asymmetrically, however, to generate daughter cells with distinct characteristics. Such asymmetric divisions are fundamental to the lifespan of a cell, to embryonic development, and to stem cell homeostasis. Asymmetric division requires coordination of cellular asymmetry and the cell division machinery. Accumulating evidence suggests that the basic molecular mechanisms that govern this process are conserved from yeast to humans. In this review we highlight similarities in the mechanisms of asymmetric cell division in yeast and Drosophila male germline stem cells (GSCs) in the hope of extracting common themes underlying several systems.
Collapse
|
31
|
Gopalakrishnan J, Mennella V, Blachon S, Zhai B, Smith AH, Megraw TL, Nicastro D, Gygi SP, Agard DA, Avidor-Reiss T. Sas-4 provides a scaffold for cytoplasmic complexes and tethers them in a centrosome. Nat Commun 2011; 2:359. [PMID: 21694707 DOI: 10.1038/ncomms1367] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Accepted: 05/24/2011] [Indexed: 12/28/2022] Open
Abstract
Centrosomes are conserved organelles that are essential for accurate cell division and cilium formation. A centrosome consists of a pair of centrioles surrounded by a protein network of pericentriolar material (PCM) that is essential for the centrosome's function. In this study, we show that Sas-4 provides a scaffold for cytoplasmic complexes (named S-CAP), which include CNN, Asl and D-PLP, proteins that are all found in the centrosomes at the vicinity of the centriole. When Sas-4 is absent, nascent procentrioles are unstable and lack PCM, and functional centrosomes are not generated. When Sas-4 is mutated, so that it cannot form S-CAP complexes, centrosomes are present but with dramatically reduced levels of PCM. Finally, purified S-CAP complexes or recombinant Sas-4 can bind centrosomes stripped of PCM, whereas recombinant CNN or Asl cannot. In summary, PCM assembly begins in the cytosol where Sas-4 provides a scaffold for pre-assembled cytoplasmic complexes before tethering of the complexes in a centrosome.
Collapse
|