Post-translational modification and regulation of actin

Jonathan R Terman1, Anna Kashina

  • 1Department of Neuroscience, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA. jonathan.terman@utsouthwestern.edu

Summary

Actin undergoes covalent modifications, impacting cellular events and host-pathogen interactions. These post-translational alterations are crucial for regulating actin dynamics in various biological processes.

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Actin Polymerization and Cell Motility01:13

Actin Polymerization and Cell Motility

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Actin cytoskeleton dynamics can produce pushing, pulling, and resistance forces that help the cell to migrate.
Introduction to Actin01:26

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Actin is a highly conserved cytoskeletal protein found abundantly in eukaryotic cells. It constitutes 10% weight of the total cellular protein in muscle cells, while in non-muscle cells, it is lower and makes up around 1–5 percent of the total cell protein. Actin found in the unicellular amoebae and complex multicellular animals is around 80% similar, demonstrating their conservation over a billion years of evolution.  Actin coding genes are conserved within species and across different species.
Generation of Straight or Branched Actin Filaments01:14

Generation of Straight or Branched Actin Filaments

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Arp2/3 Complex
Arp2/3 complex is a seven-subunit complex consisting of two proteins similar to actin- Arp2 and Arp3, and five other subunits that help keep Arp2 and Arp3 inactive. When required, the complex is...
Covalently Linked Protein Regulators02:04

Covalently Linked Protein Regulators

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These groups modify specific amino acids in a protein.
Covalently Linked Protein Regulators02:04

Covalently Linked Protein Regulators

Proteins can undergo many types of post-translational modifications, often in response to changes in their environment. These modifications play an important role in the function and stability of these proteins. Covalently linked molecules include functional groups, such as methyl, acetyl, and phosphate groups, and also small proteins, such as ubiquitin. There are around 200 different types of covalent regulators that have been identified.
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Actin Polymerization01:42

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