1
|
Balachandra S, Amodeo AA. Bellymount-Pulsed Tracking: A Novel Approach for Real-Time In vivo Imaging of Drosophila Abdominal Tissues. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.31.587498. [PMID: 38617254 PMCID: PMC11014545 DOI: 10.1101/2024.03.31.587498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
Quantitative live imaging is a valuable tool that offers insights into cellular dynamics. However, many fundamental biological processes are incompatible with current live imaging modalities. Drosophila oogenesis is a well-studied system that has provided molecular insights into a range of cellular and developmental processes. The length of the oogenesis coupled with the requirement for inputs from multiple tissues has made long-term culture challenging. Here, we have developed Bellymount-Pulsed Tracking (Bellymount-PT), which allows continuous, non-invasive live imaging of Drosophila oogenesis inside the female abdomen for up to 16 hours. Bellymount-PT improves upon the existing Bellymount technique by adding pulsed anesthesia with periods of feeding that support the long-term survival of flies during imaging. Using Bellymount-PT we measure key events of oogenesis including egg chamber growth, yolk uptake, and transfer of specific proteins to the oocyte during nurse cell dumping with high spatiotemporal precision within the abdomen of a live female.
Collapse
Affiliation(s)
- Shruthi Balachandra
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire, USA
| | - Amanda A Amodeo
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire, USA
| |
Collapse
|
2
|
Williams AM, Horne-Badovinac S. Fat2 polarizes Lar and Sema5c to coordinate the motility of collectively migrating epithelial cells. J Cell Sci 2024; 137:jcs261173. [PMID: 37593878 PMCID: PMC10508692 DOI: 10.1242/jcs.261173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 07/24/2023] [Indexed: 08/19/2023] Open
Abstract
Migrating epithelial cells globally align their migration machinery to achieve tissue-level movement. Biochemical signaling across leading-trailing cell-cell interfaces can promote this alignment by partitioning migratory behaviors like protrusion and retraction to opposite sides of the interface. However, how signaling proteins become organized at interfaces to accomplish this is poorly understood. The follicular epithelial cells of Drosophila melanogaster have two signaling modules at their leading-trailing interfaces - one composed of the atypical cadherin Fat2 (also known as Kugelei) and the receptor tyrosine phosphatase Lar, and one composed of Semaphorin5c and its receptor Plexin A. Here, we show that these modules form one interface signaling system with Fat2 at its core. Trailing edge-enriched Fat2 concentrates both Lar and Semaphorin5c at leading edges of cells, but Lar and Semaphorin5c play little role in the localization of Fat2. Fat2 is also more stable at interfaces than Lar or Semaphorin5c. Once localized, Lar and Semaphorin5c act in parallel to promote collective migration. We propose that Fat2 serves as the organizer of this interface signaling system by coupling and polarizing the distributions of multiple effectors that work together to align the migration machinery of neighboring cells.
Collapse
Affiliation(s)
- Audrey Miller Williams
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Sally Horne-Badovinac
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
- Committee on Development, Regeneration, and Stem Cell Biology, University of Chicago, Chicago, IL 60637, USA
| |
Collapse
|
3
|
Berg C, Sieber M, Sun J. Finishing the egg. Genetics 2024; 226:iyad183. [PMID: 38000906 PMCID: PMC10763546 DOI: 10.1093/genetics/iyad183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 09/27/2023] [Indexed: 11/26/2023] Open
Abstract
Gamete development is a fundamental process that is highly conserved from early eukaryotes to mammals. As germ cells develop, they must coordinate a dynamic series of cellular processes that support growth, cell specification, patterning, the loading of maternal factors (RNAs, proteins, and nutrients), differentiation of structures to enable fertilization and ensure embryonic survival, and other processes that make a functional oocyte. To achieve these goals, germ cells integrate a complex milieu of environmental and developmental signals to produce fertilizable eggs. Over the past 50 years, Drosophila oogenesis has risen to the forefront as a system to interrogate the sophisticated mechanisms that drive oocyte development. Studies in Drosophila have defined mechanisms in germ cells that control meiosis, protect genome integrity, facilitate mRNA trafficking, and support the maternal loading of nutrients. Work in this system has provided key insights into the mechanisms that establish egg chamber polarity and patterning as well as the mechanisms that drive ovulation and egg activation. Using the power of Drosophila genetics, the field has begun to define the molecular mechanisms that coordinate environmental stresses and nutrient availability with oocyte development. Importantly, the majority of these reproductive mechanisms are highly conserved throughout evolution, and many play critical roles in the development of somatic tissues as well. In this chapter, we summarize the recent progress in several key areas that impact egg chamber development and ovulation. First, we discuss the mechanisms that drive nutrient storage and trafficking during oocyte maturation and vitellogenesis. Second, we examine the processes that regulate follicle cell patterning and how that patterning impacts the construction of the egg shell and the establishment of embryonic polarity. Finally, we examine regulatory factors that control ovulation, egg activation, and successful fertilization.
Collapse
Affiliation(s)
- Celeste Berg
- Department of Genome Sciences, University of Washington, Seattle, WA 98195-5065USA
| | - Matthew Sieber
- Department of Physiology, UT Southwestern Medical Center, Dallas, TX 75390USA
| | - Jianjun Sun
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, CT 06269USA
| |
Collapse
|
4
|
Tokamov SA, Buiter S, Ullyot A, Scepanovic G, Williams AM, Fernandez-Gonzalez R, Horne-Badovinac S, Fehon RG. Cortical tension promotes Kibra degradation via Par-1. Mol Biol Cell 2024; 35:ar2. [PMID: 37903240 PMCID: PMC10881160 DOI: 10.1091/mbc.e23-06-0246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 10/17/2023] [Accepted: 10/20/2023] [Indexed: 11/01/2023] Open
Abstract
The Hippo pathway is an evolutionarily conserved regulator of tissue growth. Multiple Hippo signaling components are regulated via proteolytic degradation. However, how these degradation mechanisms are themselves modulated remains unexplored. Kibra is a key upstream pathway activator that promotes its own ubiquitin-mediated degradation upon assembling a Hippo signaling complex. Here, we demonstrate that Hippo complex-dependent Kibra degradation is modulated by cortical tension. Using classical genetic, osmotic, and pharmacological manipulations of myosin activity and cortical tension, we show that increasing cortical tension leads to Kibra degradation, whereas decreasing cortical tension increases Kibra abundance. Our study also implicates Par-1 in regulating Kib abundance downstream of cortical tension. We demonstrate that Par-1 promotes ubiquitin-mediated Kib degradation in a Hippo complex-dependent manner and is required for tension-induced Kib degradation. Collectively, our results reveal a previously unknown molecular mechanism by which cortical tension affects Hippo signaling and provide novel insights into the role of mechanical forces in growth control.
Collapse
Affiliation(s)
- Sherzod A. Tokamov
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
- Committee on Development, Regeneration, and Stem Cell Biology, The University of Chicago, Chicago, IL 60637
| | - Stephan Buiter
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
| | - Anne Ullyot
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
| | - Gordana Scepanovic
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Audrey Miller Williams
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
| | - Rodrigo Fernandez-Gonzalez
- Institute of Biomedical Engineering and Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Sally Horne-Badovinac
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
- Committee on Development, Regeneration, and Stem Cell Biology, The University of Chicago, Chicago, IL 60637
| | - Richard G. Fehon
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
- Committee on Development, Regeneration, and Stem Cell Biology, The University of Chicago, Chicago, IL 60637
| |
Collapse
|
5
|
Chess MM, Douglas W, Saunders J, Ettensohn CA. Genome-wide identification and spatiotemporal expression analysis of cadherin superfamily members in echinoderms. EvoDevo 2023; 14:15. [PMID: 38124068 PMCID: PMC10734073 DOI: 10.1186/s13227-023-00219-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 12/12/2023] [Indexed: 12/23/2023] Open
Abstract
BACKGROUND Cadherins are calcium-dependent transmembrane cell-cell adhesion proteins that are essential for metazoan development. They consist of three subfamilies: classical cadherins, which bind catenin, protocadherins, which contain 6-7 calcium-binding repeat domains, and atypical cadherins. Their functions include forming adherens junctions, establishing planar cell polarity (PCP), and regulating cell shape, proliferation, and migration. Because they are basal deuterostomes, echinoderms provide important insights into bilaterian evolution, but their only well-characterized cadherin is G-cadherin, a classical cadherin that is expressed by many embryonic epithelia. We aimed to better characterize echinoderm cadherins by conducting phylogenetic analyses and examining the spatiotemporal expression patterns of cadherin-encoding genes during Strongylocentrotus purpuratus development. RESULTS Our phylogenetic analyses conducted on two echinoid, three asteroid, and one crinoid species identified ten echinoderm cadherins, including one deuterostome-specific ortholog, cadherin-23, and an echinoderm-specific atypical cadherin that possibly arose in an echinoid-asteroid ancestor. Catenin-binding domains in dachsous-2 orthologs were found to be a deuterostome-specific innovation that was selectively lost in mouse, while those in Fat4 orthologs appeared to be Ambulacraria-specific and were selectively lost in non-crinoid echinoderms. The identified suite of echinoderm cadherins lacks vertebrate-specific innovations but contains two proteins that are present in protostomes and absent from mouse. The spatiotemporal expression patterns of four embryonically expressed cadherins (fat atypical cadherins 1 and 4, dachsous-2, and protocadherin-9) were dynamic and mirrored the expression pattern of Frizzled 5/8, a non-canonical Wnt PCP pathway receptor protein essential for archenteron morphogenesis. CONCLUSIONS The echinoderm cadherin toolkit is more similar to that of an ancient bilaterian predating protostomes and deuterostomes than it is to the suite of cadherins found in extant vertebrates. However, it also appears that deuterostomes underwent several cadherin-related innovations. Based on their similar spatiotemporal expression patterns and orthologous relationships to PCP-related and tumor-suppressing proteins, we hypothesize that sea urchin cadherins may play a role in regulating the shape and growth of embryonic epithelia and organs. Future experiments will examine cadherin expression in non-echinoid echinoderms and explore the functions of cadherins during echinoderm development.
Collapse
Affiliation(s)
- Macie M Chess
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - William Douglas
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Josiah Saunders
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Charles A Ettensohn
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.
| |
Collapse
|
6
|
Messer CL, McDonald JA. Expect the unexpected: conventional and unconventional roles for cadherins in collective cell migration. Biochem Soc Trans 2023; 51:1495-1504. [PMID: 37387360 DOI: 10.1042/bst20221202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 05/25/2023] [Accepted: 06/19/2023] [Indexed: 07/01/2023]
Abstract
Migrating cell collectives navigate complex tissue environments both during normal development and in pathological contexts such as tumor invasion and metastasis. To do this, cells in collectives must stay together but also communicate information across the group. The cadherin superfamily of proteins mediates junctional adhesions between cells, but also serve many essential functions in collective cell migration. Besides keeping migrating cell collectives cohesive, cadherins help follower cells maintain their attachment to leader cells, transfer information about front-rear polarity among the cohort, sense and respond to changes in the tissue environment, and promote intracellular signaling, in addition to other cellular behaviors. In this review, we highlight recent studies that reveal diverse but critical roles for both classical and atypical cadherins in collective cell migration, specifically focusing on four in vivo model systems in development: the Drosophila border cells, zebrafish mesendodermal cells, Drosophila follicle rotation, and Xenopus neural crest cells.
Collapse
Affiliation(s)
- C Luke Messer
- Division of Biology, Kansas State University, Manhattan, KS 66502, U.S.A
| | - Jocelyn A McDonald
- Division of Biology, Kansas State University, Manhattan, KS 66502, U.S.A
| |
Collapse
|
7
|
Williams AM, Horne-Badovinac S. Fat2 polarizes Lar and Sema5c to coordinate the motility of collectively migrating epithelial cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.28.530349. [PMID: 36909523 PMCID: PMC10002635 DOI: 10.1101/2023.02.28.530349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
Abstract
Migrating epithelial cells globally align their migration machinery to achieve tissue-level movement. Biochemical signaling across leading-trailing cell-cell interfaces can promote this alignment by partitioning migratory behaviors like protrusion and retraction to opposite sides of the interface. However, how the necessary signaling proteins become organized at this site is poorly understood. The follicular epithelial cells of Drosophila melanogaster have two signaling modules at their leading-trailing interfaces-one composed of the atypical cadherin Fat2 and the receptor tyrosine phosphatase Lar, and one composed of Semaphorin 5c and its receptor Plexin A. Here we show that these modules form one interface signaling system with Fat2 at its core. Trailing edge-enriched Fat2 concentrates both Lar and Sema5c at cells' leading edges, likely by slowing their turnover at this site. Once localized, Lar and Sema5c act in parallel to promote collective migration. Our data suggest a model in which Fat2 couples and polarizes the distributions of multiple effectors that work together to align the migration machinery of neighboring cells.
Collapse
Affiliation(s)
- Audrey Miller Williams
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL, USA
| | - Sally Horne-Badovinac
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL, USA
- Committee on Development, Regeneration, and Stem Cell Biology, University of Chicago, Chicago, IL, USA
| |
Collapse
|
8
|
Zajac AL, Williams AM, Horne-Badovinac S. A Low-Tech Flow Chamber for Live Imaging of Drosophila Egg Chambers During Drug Treatments. Methods Mol Biol 2023; 2626:277-289. [PMID: 36715910 DOI: 10.1007/978-1-0716-2970-3_14] [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: 01/31/2023]
Abstract
The Drosophila egg chamber is a powerful system to study epithelial cell collective migration and polarized basement membrane secretion. A strength of this system is the ability to capture these dynamic processes in ex vivo organ culture using high-resolution live imaging. Ex vivo culture also allows acute pharmacological or labeling treatments, extending the versatility of the system. However, many current ex vivo egg chamber culture setups do not permit easy medium exchange, preventing researchers from following individual egg chambers through multiple treatments. Here we present a method to immobilize egg chambers in an easy-to-construct flow chamber that permits imaging of the same egg chamber through repeated solution exchanges. This will allow researchers to take greater advantage of the wide variety of available pharmacological perturbations and other treatments like dyes to study dynamic processes in the egg chamber.
Collapse
Affiliation(s)
- Allison L Zajac
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, USA
| | - Audrey Miller Williams
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, USA
| | - Sally Horne-Badovinac
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, USA.
- Committee on Development, Regeneration, and Stem Cell Biology, The University of Chicago, Chicago, IL, USA.
| |
Collapse
|
9
|
Williams AM, Donoughe S, Munro E, Horne-Badovinac S. Fat2 polarizes the WAVE complex in trans to align cell protrusions for collective migration. eLife 2022; 11:e78343. [PMID: 36154691 PMCID: PMC9576270 DOI: 10.7554/elife.78343] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 09/11/2022] [Indexed: 11/13/2022] Open
Abstract
For a group of cells to migrate together, each cell must couple the polarity of its migratory machinery with that of the other cells in the cohort. Although collective cell migrations are common in animal development, little is known about how protrusions are coherently polarized among groups of migrating epithelial cells. We address this problem in the collective migration of the follicular epithelial cells in Drosophila melanogaster. In this epithelium, the cadherin Fat2 localizes to the trailing edge of each cell and promotes the formation of F-actin-rich protrusions at the leading edge of the cell behind. We show that Fat2 performs this function by acting in trans to concentrate the activity of the WASP family verprolin homolog regulatory complex (WAVE complex) at one long-lived region along each cell's leading edge. Without Fat2, the WAVE complex distribution expands around the cell perimeter and fluctuates over time, and protrusive activity is reduced and unpolarized. We further show that Fat2's influence is very local, with sub-micron-scale puncta of Fat2 enriching the WAVE complex in corresponding puncta just across the leading-trailing cell-cell interface. These findings demonstrate that a trans interaction between Fat2 and the WAVE complex creates stable regions of protrusive activity in each cell and aligns the cells' protrusions across the epithelium for directionally persistent collective migration.
Collapse
Affiliation(s)
- Audrey Miller Williams
- Department of Molecular Genetics and Cell Biology, University of ChicagoChicagoUnited States
| | - Seth Donoughe
- Department of Molecular Genetics and Cell Biology, University of ChicagoChicagoUnited States
| | - Edwin Munro
- Department of Molecular Genetics and Cell Biology, University of ChicagoChicagoUnited States
- Committee on Development, Regeneration, and Stem Cell Biology, University of ChicagoChicagoUnited States
- Institute for Biophysical Dynamics, University of ChicagoChicagoUnited States
| | - Sally Horne-Badovinac
- Department of Molecular Genetics and Cell Biology, University of ChicagoChicagoUnited States
- Committee on Development, Regeneration, and Stem Cell Biology, University of ChicagoChicagoUnited States
| |
Collapse
|