Actin-based protrusions of migrating neutrophils are intrinsically lamellar and facilitate direction changes
Leukocytes and other amoeboid cells change shape as they move, forming highly dynamic, actin-filled pseudopods. Although we understand much about the architecture and dynamics of thin lamellipodia made by slow-moving cells on flat surfaces, conventional light microscopy lacks the spatial and tempora...
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| Format: | Article |
| Language: | English |
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eLife Sciences Publications Ltd
2017-09-01
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| Series: | eLife |
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| Online Access: | https://elifesciences.org/articles/26990 |
| _version_ | 1811227869968334848 |
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| author | Lillian K Fritz-Laylin Megan Riel-Mehan Bi-Chang Chen Samuel J Lord Thomas D Goddard Thomas E Ferrin Susan M Nicholson-Dykstra Henry Higgs Graham T Johnson Eric Betzig R Dyche Mullins |
| author_facet | Lillian K Fritz-Laylin Megan Riel-Mehan Bi-Chang Chen Samuel J Lord Thomas D Goddard Thomas E Ferrin Susan M Nicholson-Dykstra Henry Higgs Graham T Johnson Eric Betzig R Dyche Mullins |
| author_sort | Lillian K Fritz-Laylin |
| collection | DOAJ |
| description | Leukocytes and other amoeboid cells change shape as they move, forming highly dynamic, actin-filled pseudopods. Although we understand much about the architecture and dynamics of thin lamellipodia made by slow-moving cells on flat surfaces, conventional light microscopy lacks the spatial and temporal resolution required to track complex pseudopods of cells moving in three dimensions. We therefore employed lattice light sheet microscopy to perform three-dimensional, time-lapse imaging of neutrophil-like HL-60 cells crawling through collagen matrices. To analyze three-dimensional pseudopods we: (i) developed fluorescent probe combinations that distinguish cortical actin from dynamic, pseudopod-forming actin networks, and (ii) adapted molecular visualization tools from structural biology to render and analyze complex cell surfaces. Surprisingly, three-dimensional pseudopods turn out to be composed of thin (<0.75 µm), flat sheets that sometimes interleave to form rosettes. Their laminar nature is not templated by an external surface, but likely reflects a linear arrangement of regulatory molecules. Although we find that Arp2/3-dependent pseudopods are dispensable for three-dimensional locomotion, their elimination dramatically decreases the frequency of cell turning, and pseudopod dynamics increase when cells change direction, highlighting the important role pseudopods play in pathfinding. |
| first_indexed | 2024-04-12T09:49:15Z |
| format | Article |
| id | doaj.art-c16f3220afe84c1989e9c378f662ee27 |
| institution | Directory Open Access Journal |
| issn | 2050-084X |
| language | English |
| last_indexed | 2024-04-12T09:49:15Z |
| publishDate | 2017-09-01 |
| publisher | eLife Sciences Publications Ltd |
| record_format | Article |
| series | eLife |
| spelling | doaj.art-c16f3220afe84c1989e9c378f662ee272022-12-22T03:37:52ZengeLife Sciences Publications LtdeLife2050-084X2017-09-01610.7554/eLife.26990Actin-based protrusions of migrating neutrophils are intrinsically lamellar and facilitate direction changesLillian K Fritz-Laylin0https://orcid.org/0000-0002-9237-9403Megan Riel-Mehan1Bi-Chang Chen2Samuel J Lord3https://orcid.org/0000-0002-2785-989XThomas D Goddard4Thomas E Ferrin5Susan M Nicholson-Dykstra6Henry Higgs7Graham T Johnson8Eric Betzig9R Dyche Mullins10https://orcid.org/0000-0002-0871-5479Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United StatesDepartment of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, United StatesJanelia Research Campus, Howard Hughes Medical Institute, Ashburn, United StatesDepartment of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United StatesDepartment of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, United StatesDepartment of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, United StatesDepartment of Biochemistry and Cell Biology, Dartmouth Geisel School of Medicine, Hanover, United StatesDepartment of Biochemistry and Cell Biology, Dartmouth Geisel School of Medicine, Hanover, United StatesDepartment of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, United States; Animated Cell, Allen Institute for Cell Science, Seattle, United StatesJanelia Research Campus, Howard Hughes Medical Institute, Ashburn, United StatesDepartment of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United StatesLeukocytes and other amoeboid cells change shape as they move, forming highly dynamic, actin-filled pseudopods. Although we understand much about the architecture and dynamics of thin lamellipodia made by slow-moving cells on flat surfaces, conventional light microscopy lacks the spatial and temporal resolution required to track complex pseudopods of cells moving in three dimensions. We therefore employed lattice light sheet microscopy to perform three-dimensional, time-lapse imaging of neutrophil-like HL-60 cells crawling through collagen matrices. To analyze three-dimensional pseudopods we: (i) developed fluorescent probe combinations that distinguish cortical actin from dynamic, pseudopod-forming actin networks, and (ii) adapted molecular visualization tools from structural biology to render and analyze complex cell surfaces. Surprisingly, three-dimensional pseudopods turn out to be composed of thin (<0.75 µm), flat sheets that sometimes interleave to form rosettes. Their laminar nature is not templated by an external surface, but likely reflects a linear arrangement of regulatory molecules. Although we find that Arp2/3-dependent pseudopods are dispensable for three-dimensional locomotion, their elimination dramatically decreases the frequency of cell turning, and pseudopod dynamics increase when cells change direction, highlighting the important role pseudopods play in pathfinding.https://elifesciences.org/articles/26990cell migrationmicroscopyvisualizationactinarp2/3amoeboid motility |
| spellingShingle | Lillian K Fritz-Laylin Megan Riel-Mehan Bi-Chang Chen Samuel J Lord Thomas D Goddard Thomas E Ferrin Susan M Nicholson-Dykstra Henry Higgs Graham T Johnson Eric Betzig R Dyche Mullins Actin-based protrusions of migrating neutrophils are intrinsically lamellar and facilitate direction changes eLife cell migration microscopy visualization actin arp2/3 amoeboid motility |
| title | Actin-based protrusions of migrating neutrophils are intrinsically lamellar and facilitate direction changes |
| title_full | Actin-based protrusions of migrating neutrophils are intrinsically lamellar and facilitate direction changes |
| title_fullStr | Actin-based protrusions of migrating neutrophils are intrinsically lamellar and facilitate direction changes |
| title_full_unstemmed | Actin-based protrusions of migrating neutrophils are intrinsically lamellar and facilitate direction changes |
| title_short | Actin-based protrusions of migrating neutrophils are intrinsically lamellar and facilitate direction changes |
| title_sort | actin based protrusions of migrating neutrophils are intrinsically lamellar and facilitate direction changes |
| topic | cell migration microscopy visualization actin arp2/3 amoeboid motility |
| url | https://elifesciences.org/articles/26990 |
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