#cell movement

Ready for Actin

Racing to the scene of an infection, immune cells like macrophages need to move through crowded tissues. How do they manage this without getting squished? Researchers studying macrophages in fruit flies (Drosophila melanogaster) find a protein called FOS helps to strengthen each cell’s internal skeleton, creating a ‘tank-like’ shell of actin fibres which cushions the fragile nucleus as the cells push into the tissue. Here macrophages (highlighted in green) spread into (unseen here) embryos under a high-powered microscope – cells with impaired FOS (right) have a weaker protective shell and move more slowly. Humans have similar macrophages and, researchers believe, similar tank-building FOS genes. The new challenge is to support FOS in strengthening our immune cells when invading tumours as a form of cancer immunotherapy.

Written by John Ankers

Image from work by Kunal Sharma and colleagues

Institute of Science and Technology Austria, Klosterneuburg, Austria

Video originally published with a Creative Commons Attribution 4.0 International (CC BY 4.0)

Published in PLOS Biology, January 2022

-- an organelle

-- cellular appendages

-- assist in movement

-- contain a microtubule core with cytoplasm covered in a plasma membrane

-- move in beating or waving motions

Cilia -- short -- numerous -- functions to sweep substances over the cell surface -- longer than microvilli

Flagellum -- long -- singular -- propels cell

Integrins, Cadherins, Signaling and the Cytoskeleton

Larry H. Bernstein, MD, FCAP, Reviewer and Curator

CSO, Leaders in Pharmaceutical Intelligence

Integrins, Cadherins, Signaling and the Cytoskeleton

  We have reviewed the cytoskeleton, cytoskeleton pores and ionic translocation under lipids. We shall now look at this again, with specific attention to proteins, transporters and signaling.

  Integrins and extracellular matrix in mechanotransduction

New type of cell movement discovered

In a new study from the University of Pennsylvania and National Institute of Dental and Craniofacial Research, scientists used an innovative technique to study how cells move in a three-dimensional matrix, similar to the structure of certain tissues, such as the skin. They discovered an entirely new type of cell movement whereby the nucleus helps propel cells through the matrix like a piston in an engine, generating pressure that thrusts the cell's plasma membrane forward.

"Our work elucidated a highly intriguing question: how cells move when they are in the complex and physiologically relevant environment of a 3-D extracellular matrix," said Hyun (Michel) Koo, a professor in the Department of Orthodontics at Penn's School of Dental Medicine. "We discovered that the nucleus can act as a piston that physically compartmentalizes the cell cytoplasm and increases the hydrostatic pressure driving the cell motility within a 3-D matrix."

R. J. Petrie, H. Koo, K. M. Yamada. Generation of compartmentalized pressure by a nuclear piston governs cell motility in a 3D matrix. Science, 2014; 345 (6200): 1062 DOI: 10.1126/science.1256965