Related Experiment Video
Updated: Jan 11, 2026
09:58
RhoC GTPase Activation Assay
Published on: August 22, 2010
13.0K
Local RhoA activation induces septin recruitment
Shreya Chandrasekar1, Margaret E Utgaard1, Bradley Somerfield1
1Dept. Cell & Molecular Physiology, Loyola University Chicago, Stritch School of Medicine, Maywood, IL 60153.
Biorxiv : the Preprint Server for Biology
|November 19, 2025
Summary
RhoA signaling influences the septin cytoskeleton, a key component of cell structure. Local RhoA activation, but not myosin changes, increases septin accumulation, revealing new roles for septins in cell remodeling.
Area of Science:
- Cell Biology
- Cytoskeletal Dynamics
- Molecular Cell Biology
Background:
- The actin cytoskeleton is crucial for cell shape and structure.
- RhoA GTPase regulates the actomyosin cytoskeleton, but its role in septin cytoskeleton regulation is unclear.
- Traditional assays struggle to resolve spatial and temporal RhoA interactions.
Purpose of the Study:
- To investigate how RhoA and myosin impact the septin cytoskeleton.
- To explore the spatial and temporal effects of RhoA signaling on septin organization.
- To elucidate the mechanism by which RhoA influences septin structure.
Main Methods:
- Utilized optogenetic tools for spatial and temporal control of cellular processes.
- Manipulated myosin localization and contractile force.
- Activated RhoA locally within cells.
- Assessed changes in septin cytoskeleton architecture and accumulation.
Main Results:
- Local accumulation or increased activity of myosin did not alter septin architecture.
- Local activation of RhoA led to a significant local increase in septin accumulation.
- This RhoA-induced septin increase was independent of the scaffolding protein anillin.
Conclusions:
- RhoA signaling directly impacts septin cytoskeleton organization.
- Myosin activity alone is insufficient to remodel the septin cytoskeleton.
- Septins may play a broader role in mediating RhoA signaling through cytoskeletal remodeling.
More Related Videos
11:50Purification and Quality Control of Recombinant Septin Complexes for Cell-Free Reconstitution
Published on: June 23, 2022
2.6K
12:35Author Spotlight: Optogenetic Inhibition of Rho1-Mediated Actomyosin Contractility Coupled with Measurement of Epithelial Tension in Drosophila Embryos
Published on: April 14, 2023
1.8K
Related Concept Videos
01:21Cell Polarization by Rho Proteins
3.5K
Cell polarity is the asymmetric distribution of cellular and membrane components, making one side of the cell different from the other. This polarity is essential to many processes such as embryogenesis, axon migration, glucose transport across epithelial cells, and directional cell migration. A migrating cell responds to intracellular or extracellular signals via molecular cascades that reorganize the actin cytoskeleton to establish this polarity. In these cells, the Rho family proteins Cdc42,...
3.5K
01:24Small GTPases - Ras and Rho
5.2K
Ras and Rho are small monomeric GTPases that act downstream of receptor tyrosine kinase (RTK) and regulate various cellular processes. These GTPases switch between active and inactive states by binding to guanine nucleotides.
Three regulatory proteins control their activity:
Three regulatory proteins control their activity:
5.2K
02:15The Contractile Ring
7.1K
Contractile rings are composed of microfilaments and are responsible for separating the daughter cells during cytokinesis. Contractile ring assembly proceeds along with other cell cycle events; however, very few mechanistic details are known about the timing and coordination of the contractile rings with the cell cycle.
A small GTPase, RhoA, controls the function and assembly of the contractile ring. RhoA belongs to the Ras superfamily of proteins. The activation of formins by RhoA promotes...
A small GTPase, RhoA, controls the function and assembly of the contractile ring. RhoA belongs to the Ras superfamily of proteins. The activation of formins by RhoA promotes...
7.1K
01:19Septins
2.2K
Septins are protein filaments forming the cytoskeleton along with the microtubules, microfilaments, intermediate filaments, and other accessory proteins. In 1971 while studying the cell division cycle in mutant Saccharomyces cerevisiae Harwell et al. first identified the septin-related genes playing a crucial role in yeast cytokinesis. Fluorescence microscopy revealed that these proteins localize at the budding neck as rings. These ring-like proteins were then named Septins by John Pringle, and...
2.2K
01:25Rab Cascades
3.4K
Rab GTPases act in a regulated cascade during membrane fusion, helping the lipid bilayers mix. The Rab family of proteins are active when bound to GTP, and inactive when bound to GDP. Hence, they act as guanine nucleotide-dependent molecular switches. Rab-GTP recognizes and binds to long or short-range tethering proteins to capture the target vesicle. These tethers coordinate with SNAREs on the vesicle and the target membrane to assemble the trans SNARE complex that locks the mixing bilayers.
3.4K
01:02Role of Septins
2.1K
Septins are the recently discovered fourth major protein component of the cytoskeleton, along with microfilaments, microtubules, and intermediate filaments. These proteins can associate with other cytoskeletal filaments and carry out varied roles or can be free-floating in the cytoplasm.
Cellular Functions of Septins
Recent studies have revealed the multifaceted roles of septins in various cellular processes such as cytokinesis, ciliogenesis, and neurogenesis. Septins act as scaffolds and...
Cellular Functions of Septins
Recent studies have revealed the multifaceted roles of septins in various cellular processes such as cytokinesis, ciliogenesis, and neurogenesis. Septins act as scaffolds and...
2.1K