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Penkert RR, LaFoya B, Moholt-Siebert L, Vargas E, Welch SE, Prehoda KE. The Drosophila neuroblast polarity cycle at a glance. J Cell Sci 2024; 137:jcs261789. [PMID: 38465513 PMCID: PMC10984279 DOI: 10.1242/jcs.261789] [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] [Indexed: 03/12/2024] Open
Abstract
Drosophila neural stem cells, or neuroblasts, rapidly proliferate during embryonic and larval development to populate the central nervous system. Neuroblasts divide asymmetrically to create cellular diversity, with each division producing one sibling cell that retains the neuroblast fate and another that differentiates into glia or neurons. This asymmetric outcome is mediated by the transient polarization of numerous factors to the cell cortex during mitosis. The powerful genetics and outstanding imaging tractability of the neuroblast make it an excellent model system for studying the mechanisms of cell polarity. This Cell Science at a Glance article and the accompanying poster explore the phases of the neuroblast polarity cycle and the regulatory circuits that control them. We discuss the key features of the cycle - the targeted recruitment of proteins to specific regions of the plasma membrane and multiple phases of highly dynamic actomyosin-dependent cortical flows that pattern both protein distribution and membrane structure.
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2
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Mullan TW, Felton T, Tam J, Kasem O, Yeung TJ, Memar N, Schnabel R, Poole RJ. Control of successive unequal cell divisions by neural cell fate regulators determines embryonic neuroblast cell size. Development 2024; 151:dev200981. [PMID: 38205939 PMCID: PMC10911278 DOI: 10.1242/dev.200981] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 01/02/2024] [Indexed: 01/12/2024]
Abstract
Asymmetric cell divisions often generate daughter cells of unequal size in addition to different fates. In some contexts, daughter cell size asymmetry is thought to be a key input to specific binary cell fate decisions. An alternative possibility is that unequal division is a mechanism by which a variety of cells of different sizes are generated during embryonic development. We show here that two unequal cell divisions precede neuroblast formation in the C lineage of Caenorhabditis elegans. The equalisation of these divisions in a pig-1/MELK mutant background has little effect on neuroblast specification. Instead, we demonstrate that let-19/MDT13 is a regulator of the proneural basic helix-loop-helix transcription factor hlh-14/ASCL1 and find that both are required to concomitantly regulate the acquisition of neuroblast identity and neuroblast cell size. Thus, embryonic neuroblast cell size in this lineage is progressively regulated in parallel with identity by key neural cell fate regulators. We propose that key cell fate determinants have a previously unappreciated function in regulating unequal cleavage, and therefore cell size, of the progenitor cells whose daughter cell fates they then go on to specify.
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Affiliation(s)
- Thomas W. Mullan
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Terry Felton
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Janis Tam
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Osama Kasem
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Tim J. Yeung
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Nadin Memar
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
- Institut für Genetik, TU Braunschweig, D-38106 Braunschweig, Germany
| | - Ralf Schnabel
- Institut für Genetik, TU Braunschweig, D-38106 Braunschweig, Germany
| | - Richard J. Poole
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
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3
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Hsu CR, Sangha G, Fan W, Zheng J, Sugioka K. Contractile ring mechanosensation and its anillin-dependent tuning during early embryogenesis. Nat Commun 2023; 14:8138. [PMID: 38065974 PMCID: PMC10709429 DOI: 10.1038/s41467-023-43996-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 11/27/2023] [Indexed: 12/18/2023] Open
Abstract
Cytokinesis plays crucial roles in morphogenesis. Previous studies have examined how tissue mechanics influences the position and closure direction of the contractile ring. However, the mechanisms by which the ring senses tissue mechanics remain largely elusive. Here, we show the mechanism of contractile ring mechanosensation and its tuning during asymmetric ring closure of Caenorhabditis elegans embryos. Integrative analysis of ring closure and cell cortex dynamics revealed that mechanical suppression of the ring-directed cortical flow is associated with asymmetric ring closure. Consistently, artificial obstruction of ring-directed cortical flow induces asymmetric ring closure in otherwise symmetrically dividing cells. Anillin is vital for mechanosensation. Our genetic analysis suggests that the positive feedback loop among ring-directed cortical flow, myosin enrichment, and ring constriction constitutes a mechanosensitive pathway driving asymmetric ring closure. These findings and developed tools should advance the 4D mechanobiology of cytokinesis in more complex tissues.
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Affiliation(s)
- Christina Rou Hsu
- Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T1Z3, Canada
- Department of Zoology, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T1Z3, Canada
| | - Gaganpreet Sangha
- Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T1Z3, Canada
- Department of Zoology, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T1Z3, Canada
| | - Wayne Fan
- Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T1Z3, Canada
- Department of Zoology, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T1Z3, Canada
| | - Joey Zheng
- Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T1Z3, Canada
- Department of Zoology, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T1Z3, Canada
| | - Kenji Sugioka
- Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T1Z3, Canada.
- Department of Zoology, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T1Z3, Canada.
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4
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LaFoya B, Prehoda KE. Consumption of a polarized membrane reservoir drives asymmetric membrane expansion during the unequal divisions of neural stem cells. Dev Cell 2023; 58:993-1003.e3. [PMID: 37116487 PMCID: PMC10247545 DOI: 10.1016/j.devcel.2023.04.006] [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: 05/03/2022] [Revised: 11/23/2022] [Accepted: 04/05/2023] [Indexed: 04/30/2023]
Abstract
The asymmetric divisions of Drosophila neural stem cells (NSCs) produce unequally sized siblings, with most volume directed into the sibling that retains the NSC fate. Sibling size asymmetry results from the preferential expansion of the NSC sibling surface during division. Here, we show that a polarized membrane reservoir constructed by the NSC in early mitosis provides the source for expansion. The reservoir is formed from membrane domains that contain folds and microvilli that become polarized by apically directed cortical flows of actomyosin early in mitosis. When furrow ingression begins and internal pressure increases, the stores of membrane within the apical reservoir are rapidly consumed. Expansion is substantially diminished in NSCs that lack a reservoir, and membrane expansion equalizes when the reservoir is not polarized. Our results suggest that the cortical flows that remodel the plasma membrane during asymmetric cell division function to satisfy the dynamic surface area requirements of unequally dividing cells.
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Affiliation(s)
- Bryce LaFoya
- Institute of Molecular Biology, Department of Chemistry and Biochemistry, 1229 University of Oregon, Eugene, OR 97403, USA
| | - Kenneth E Prehoda
- Institute of Molecular Biology, Department of Chemistry and Biochemistry, 1229 University of Oregon, Eugene, OR 97403, USA.
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5
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Montembault E, Deduyer I, Claverie MC, Bouit L, Tourasse NJ, Dupuy D, McCusker D, Royou A. Two RhoGEF isoforms with distinct localisation control furrow position during asymmetric cell division. Nat Commun 2023; 14:3209. [PMID: 37268622 DOI: 10.1038/s41467-023-38912-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 05/19/2023] [Indexed: 06/04/2023] Open
Abstract
Cytokinesis partitions cellular content between daughter cells. It relies on the formation of an acto-myosin contractile ring, whose constriction induces the ingression of the cleavage furrow between the segregated chromatids. Rho1 GTPase and its RhoGEF (Pbl) are essential for this process. However, how Rho1 is regulated to sustain furrow ingression while maintaining correct furrow position remains poorly defined. Here, we show that during asymmetric division of Drosophila neuroblasts, Rho1 is controlled by two Pbl isoforms with distinct localisation. Spindle midzone- and furrow-enriched Pbl-A focuses Rho1 at the furrow to sustain efficient ingression, while Pbl-B pan-plasma membrane localization promotes the broadening of Rho1 activity and the subsequent enrichment of myosin on the entire cortex. This enlarged zone of Rho1 activity is critical to adjust furrow position, thereby preserving correct daughter cell size asymmetry. Our work highlights how the use of isoforms with distinct localisation makes an essential process more robust.
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Affiliation(s)
- Emilie Montembault
- CNRS, UMR5095, University of Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France
- CNRS, UMR5095, University of Bordeaux, Institut de Biologie et Génétique Cellulaire, 1 rue Camille Saint-Saëns, 33077, Bordeaux, France
| | - Irène Deduyer
- CNRS, UMR5095, University of Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France
- CNRS, UMR5095, University of Bordeaux, Institut de Biologie et Génétique Cellulaire, 1 rue Camille Saint-Saëns, 33077, Bordeaux, France
| | - Marie-Charlotte Claverie
- CNRS, UMR5095, University of Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France
- CNRS, UMR5095, University of Bordeaux, Institut de Biologie et Génétique Cellulaire, 1 rue Camille Saint-Saëns, 33077, Bordeaux, France
| | - Lou Bouit
- CNRS, UMR5095, University of Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France
- CNRS, UMR5297, University of Bordeaux, 146 Rue Léo Saignat, 33076, Bordeaux, France
| | - Nicolas J Tourasse
- University of Bordeaux, INSERM, U1212, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France
| | - Denis Dupuy
- University of Bordeaux, INSERM, U1212, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France
| | - Derek McCusker
- CNRS, UMR5095, University of Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France
- CNRS, UMR5095, University of Bordeaux, Institut de Biologie et Génétique Cellulaire, 1 rue Camille Saint-Saëns, 33077, Bordeaux, France
| | - Anne Royou
- CNRS, UMR5095, University of Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France.
- CNRS, UMR5095, University of Bordeaux, Institut de Biologie et Génétique Cellulaire, 1 rue Camille Saint-Saëns, 33077, Bordeaux, France.
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6
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Sugioka K. Symmetry-breaking of animal cytokinesis. Semin Cell Dev Biol 2021; 127:100-109. [PMID: 34955355 DOI: 10.1016/j.semcdb.2021.12.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 12/05/2021] [Accepted: 12/16/2021] [Indexed: 12/24/2022]
Abstract
Cytokinesis is a mechanism that separates dividing cells via constriction of a supramolecular structure, the contractile ring. In animal cells, three modes of symmetry-breaking of cytokinesis result in unilateral cytokinesis, asymmetric cell division, and oriented cell division. Each mode of cytokinesis plays a significant role in tissue patterning and morphogenesis by the mechanisms that control the orientation and position of the contractile ring relative to the body axis. Despite its significance, the mechanisms involved in the symmetry-breaking of cytokinesis remain unclear in many cell types. Classical embryologists have identified that the geometric relationship between the mitotic spindle and cell cortex induces cytokinesis asymmetry; however, emerging evidence suggests that a concerted flow of compressional cell-cortex materials (cortical flow) is a spindle-independent driving force in spatial cytokinesis control. This review provides an overview of both classical and emerging mechanisms of cytokinesis asymmetry and their roles in animal development.
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Affiliation(s)
- Kenji Sugioka
- Life Sciences Institute, The University of British Columbia, Vancouver, BC V6T1Z3, Canada; Department of Zoology, The University of British Columbia, Vancouver, BC V6T1Z3, Canada.
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7
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Phase Separation and Mechanical Forces in Regulating Asymmetric Cell Division of Neural Stem Cells. Int J Mol Sci 2021; 22:ijms221910267. [PMID: 34638607 PMCID: PMC8508713 DOI: 10.3390/ijms221910267] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 09/20/2021] [Accepted: 09/21/2021] [Indexed: 12/13/2022] Open
Abstract
Asymmetric cell division (ACD) of neural stem cells and progenitors not only renews the stem cell population but also ensures the normal development of the nervous system, producing various types of neurons with different shapes and functions in the brain. One major mechanism to achieve ACD is the asymmetric localization and uneven segregation of intracellular proteins and organelles into sibling cells. Recent studies have demonstrated that liquid-liquid phase separation (LLPS) provides a potential mechanism for the formation of membrane-less biomolecular condensates that are asymmetrically distributed on limited membrane regions. Moreover, mechanical forces have emerged as pivotal regulators of asymmetric neural stem cell division by generating sibling cell size asymmetry. In this review, we will summarize recent discoveries of ACD mechanisms driven by LLPS and mechanical forces.
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8
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Taubenberger AV, Baum B, Matthews HK. The Mechanics of Mitotic Cell Rounding. Front Cell Dev Biol 2020; 8:687. [PMID: 32850812 PMCID: PMC7423972 DOI: 10.3389/fcell.2020.00687] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/06/2020] [Indexed: 12/21/2022] Open
Abstract
When animal cells enter mitosis, they round up to become spherical. This shape change is accompanied by changes in mechanical properties. Multiple studies using different measurement methods have revealed that cell surface tension, intracellular pressure and cortical stiffness increase upon entry into mitosis. These cell-scale, biophysical changes are driven by alterations in the composition and architecture of the contractile acto-myosin cortex together with osmotic swelling and enable a mitotic cell to exert force against the environment. When the ability of cells to round is limited, for example by physical confinement, cells suffer severe defects in spindle assembly and cell division. The requirement to push against the environment to create space for spindle formation is especially important for cells dividing in tissues. Here we summarize the evidence and the tools used to show that cells exert rounding forces in mitosis in vitro and in vivo, review the molecular basis for this force generation and discuss its function for ensuring successful cell division in single cells and for cells dividing in normal or diseased tissues.
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Affiliation(s)
- Anna V. Taubenberger
- Biotechnology Center, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany
| | - Buzz Baum
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Helen K. Matthews
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
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9
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Mechanical regulation of cell size, fate, and behavior during asymmetric cell division. Curr Opin Cell Biol 2020; 67:9-16. [PMID: 32768924 DOI: 10.1016/j.ceb.2020.07.002] [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: 04/03/2020] [Revised: 06/15/2020] [Accepted: 07/06/2020] [Indexed: 01/03/2023]
Abstract
Asymmetric cell division (ACD) is an evolutionary conserved mechanism used by prokaryotes and eukaryotes alike to generate cell diversity. ACD can be manifested in biased segregation of macromolecules or differential partitioning of cell organelles. Cells are also constantly subject to extrinsic or intrinsic mechanical forces, influencing cell behavior and fate. During ACD, cell intrinsic forces generated through the spatiotemporal regulation of the actomyosin cytoskeleton can influence sibling cell size. External mechanical stresses are further translated by transcriptional coactivators or mechanically gated ion channels. Here, we will discuss recent literature, exploring how mechanical cues influence various aspects of ACD and stem cell behavior, and how these mechanical cues contribute to cell fate decisions.
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10
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Abstract
Asymmetric cell division (ACD) is an evolutionarily conserved mechanism used by prokaryotes and eukaryotes alike to control cell fate and generate cell diversity. A detailed mechanistic understanding of ACD is therefore necessary to understand cell fate decisions in health and disease. ACD can be manifested in the biased segregation of macromolecules, the differential partitioning of cell organelles, or differences in sibling cell size or shape. These events are usually preceded by and influenced by symmetry breaking events and cell polarization. In this Review, we focus predominantly on cell intrinsic mechanisms and their contribution to cell polarization, ACD and binary cell fate decisions. We discuss examples of polarized systems and detail how polarization is established and, whenever possible, how it contributes to ACD. Established and emerging model organisms will be considered alike, illuminating both well-documented and underexplored forms of polarization and ACD.
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Affiliation(s)
- Bharath Sunchu
- Department of Biology, University of Washington, Life Science Building, Seattle, WA 98195, USA
| | - Clemens Cabernard
- Department of Biology, University of Washington, Life Science Building, Seattle, WA 98195, USA
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11
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Loyer N, Januschke J. Where does asymmetry come from? Illustrating principles of polarity and asymmetry establishment in Drosophila neuroblasts. Curr Opin Cell Biol 2020; 62:70-77. [DOI: 10.1016/j.ceb.2019.07.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 07/15/2019] [Accepted: 07/16/2019] [Indexed: 12/22/2022]
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12
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Wesley CC, Mishra S, Levy DL. Organelle size scaling over embryonic development. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2020; 9:e376. [PMID: 32003549 DOI: 10.1002/wdev.376] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 12/19/2019] [Accepted: 01/08/2020] [Indexed: 12/13/2022]
Abstract
Cell division without growth results in progressive cell size reductions during early embryonic development. How do the sizes of intracellular structures and organelles scale with cell size and what are the functional implications of such scaling relationships? Model organisms, in particular Caenorhabditis elegans worms, Drosophila melanogaster flies, Xenopus laevis frogs, and Mus musculus mice, have provided insights into developmental size scaling of the nucleus, mitotic spindle, and chromosomes. Nuclear size is regulated by nucleocytoplasmic transport, nuclear envelope proteins, and the cytoskeleton. Regulators of microtubule dynamics and chromatin compaction modulate spindle and mitotic chromosome size scaling, respectively. Developmental scaling relationships for membrane-bound organelles, like the endoplasmic reticulum, Golgi, mitochondria, and lysosomes, have been less studied, although new imaging approaches promise to rectify this deficiency. While models that invoke limiting components and dynamic regulation of assembly and disassembly can account for some size scaling relationships in early embryos, it will be exciting to investigate the contribution of newer concepts in cell biology such as phase separation and interorganellar contacts. With a growing understanding of the underlying mechanisms of organelle size scaling, future studies promise to uncover the significance of proper scaling for cell function and embryonic development, as well as how aberrant scaling contributes to disease. This article is categorized under: Establishment of Spatial and Temporal Patterns > Regulation of Size, Proportion, and Timing Early Embryonic Development > Fertilization to Gastrulation Comparative Development and Evolution > Model Systems.
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Affiliation(s)
- Chase C Wesley
- Department of Molecular Biology, University of Wyoming, Laramie, Wyoming
| | - Sampada Mishra
- Department of Molecular Biology, University of Wyoming, Laramie, Wyoming
| | - Daniel L Levy
- Department of Molecular Biology, University of Wyoming, Laramie, Wyoming
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13
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Winkley K, Ward S, Reeves W, Veeman M. Iterative and Complex Asymmetric Divisions Control Cell Volume Differences in Ciona Notochord Tapering. Curr Biol 2019; 29:3466-3477.e4. [PMID: 31607534 DOI: 10.1016/j.cub.2019.08.056] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/29/2019] [Accepted: 08/21/2019] [Indexed: 12/12/2022]
Abstract
The notochord of the invertebrate chordate Ciona forms a tapered rod at tailbud stages consisting of only 40 cylindrical cells in a single-file column. This tapered shape involves differences in notochord cell volume along the anterior-posterior axis. Here, we quantify sibling cell volume asymmetry throughout the developing notochord and find that there are distinctive patterns of unequal cleavage in all 4 bilateral pairs of A-line primary notochord founder cells and also in the B-line-derived secondary notochord founder cells. A quantitative model confirms that the observed patterns of unequal cleavage are sufficient to explain all the anterior-posterior variation in notochord cell volume. Many examples are known of cells that divide asymmetrically to give daughter cells of different size and fate. Here, by contrast, a series of subtle but iterative and finely patterned asymmetric divisions controls the shape of an entire organ. Quantitative 3D analysis of cell shape and spindle positioning allows us to infer multiple cellular mechanisms driving these unequal cleavages, including polarized displacements of the mitotic spindle, contributions from the shape of the mother cell, and late changes occurring between anaphase and abscission that potentially involve differential cortical contractility. We infer differential use of these mechanisms between different notochord blastomeres and also between different rounds of cell division. These results demonstrate a new role for asymmetric division in directly shaping a developing organ and point toward complex underlying mechanisms.
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Affiliation(s)
- Konner Winkley
- Division of Biology, Kansas State University, 1717 Claflin Road, Manhattan, KS 66506, USA
| | - Spencer Ward
- Division of Biology, Kansas State University, 1717 Claflin Road, Manhattan, KS 66506, USA
| | - Wendy Reeves
- Division of Biology, Kansas State University, 1717 Claflin Road, Manhattan, KS 66506, USA
| | - Michael Veeman
- Division of Biology, Kansas State University, 1717 Claflin Road, Manhattan, KS 66506, USA.
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14
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Aguilar G, Vigano MA, Affolter M, Matsuda S. Reflections on the use of protein binders to study protein function in developmental biology. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2019; 8:e356. [PMID: 31265212 PMCID: PMC6851689 DOI: 10.1002/wdev.356] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 06/03/2019] [Accepted: 06/04/2019] [Indexed: 02/01/2023]
Abstract
Studies in the field of developmental biology aim to unravel how a fertilized egg develops into an adult organism and how proteins and other macromolecules work together during this process. With regard to protein function, most of the developmental studies have used genetic and RNA interference approaches, combined with biochemical analyses, to reach this goal. However, there always remains much room for interpretation on how a given protein functions, because proteins work together with many other molecules in complex regulatory networks and it is not easy to reveal the function of one given protein without affecting the networks. Likewise, it has remained difficult to experimentally challenge and/or validate the proposed concepts derived from mutant analyses without tools that directly manipulate protein function in a predictable manner. Recently, synthetic tools based on protein binders such as scFvs, nanobodies, DARPins, and others have been applied in developmental biology to directly manipulate target proteins in a predicted manner. Although such tools would have a great impact in filling the gap of knowledge between mutant phenotypes and protein functions, careful investigations are required when applying functionalized protein binders to fundamental questions in developmental biology. In this review, we first summarize how protein binders have been used in the field, and then reflect on possible guidelines for applying such tools to study protein functions in developmental biology. This article is categorized under: Technologies > Analysis of Proteins Establishment of Spatial and Temporal Patterns > Gradients Invertebrate Organogenesis > Flies.
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