F-Actin—A Crucial Protein for Cellular Function and Motility
In most eukaryotic cells, actin is the most abundant protein. As an important part of the cytoskeleton, actin is essential for cell stability and morphogenesis. It is involved in many crucial processes, such as cell division, endocytosis, and cell migration.
Actin is present in two forms:
- Monomeric, globular G-actin
- Polymeric, filamentous F-actin
The monomeric G-actin has the ability to polymerize, thereby creating the F-actin polymer filaments (also named actin filaments or microfilaments). These microfilaments are an essential part of the cytoskeleton and build up many higher order structures in cells (e.g., stress fibers, lamellipodia, and filopodia).
Given these numerous and important functions in the cellular architecture, it is no surprise that the visualization of F-actin is indispensable in many research areas:
- Cell biology
- Cellular structure and morphology
- Function and regulation of actin binding proteins
- Chemotaxis and migration
- Muscle cell research
- Cytoskeleton biophysics
- Cellular adherence, cellular interactions, interactions with ECM
- Cancer research
LifeAct stains filamentous actin structures in living or fixed eukaryotic cells and tissues having the lowest potential interference with actin dynamics in vivo and in vitro.
T. Oda, M. Iwasa, T. Aihara, Y. Maéda and A. Narita. The nature of the globular- to fibrous-actin transition. Nature, 2009, 10.1038/nature07685
M. Melak, M. Plessner, and R. Grosse. Actin visualization at a glance. Journal of Cell Science, 2017, 10.1242/jcs.204487
G-actin has the ability to polymerize, resulting in the F-actin polymer. This process is reversible, allowing the actin monomers to dissociate again from the ends of the actin filaments.