More Like this

1. Actin filament sliding in CaMKII-actin bundles

   https://doi.org/10.1016/j.bpj.2022.11.1051  

   Basurco, Carlos A.; Schafer, Nicholas P.; Waxham, Neal; Cheung, Margaret S.; Wolynes, Peter G. (February 2023, Biophysical Journal)
2. Actin chromobody imaging reveals sub-organellar actin dynamics

   https://doi.org/10.1038/s41592-020-0926-5  

   Schiavon, Cara R.; Zhang, Tong; Zhao, Bing; Moore, Andrew S.; Wales, Pauline; Andrade, Leonardo R.; Wu, Melissa; Sung, Tsung-Chang; Dayn, Yelena; Feng, Jasmine W.; et al (September 2020, Nature Methods)

   null (Ed.)
3. Morphometric analysis of actin networks

   https://doi.org/10.1091/mbc.E24-06-0248  

   Akenuwa, Oghosa H; Gu, Jinmo; Nebenführ, Andreas; Abel, Steven M (December 2024, Molecular Biology of the Cell)

   Zaritsky, Assaf (Ed.)

   The organization of cytoskeletal elements is pivotal for coordinating intracellular transport in eukaryotic cells. Several quantitative measures based on image analysis have been proposed to characterize morphometric features of fluorescently labeled actin networks. While helpful in detecting differences in actin organization between treatments or genotypes, the accuracy of these measures could not be rigorously assessed due to a lack of ground-truth data to which they could be compared. To overcome this limitation, we utilized coarse-grained computer simulations of actin filaments and cross-linkers to generate synthetic actin networks with varying levels of bundling. We converted the simulated networks into pseudofluorescence images similar to images obtained using confocal microscopy. Using both published and novel analysis procedures, we extracted a series of morphometric parameters and benchmarked them against analogous measures based on the ground-truth actin configurations. Our analysis revealed a set of parameters that reliably reports on actin network density, orientation, ordering, and bundling. Application of these morphometric parameters to root epidermal cells of Arabidopsis thaliana revealed subtle changes in network organization between wild-type and mutant cells. This work provides robust measures that can be used to quantify features of actin networks and characterize changes in actin organization for different experimental conditions. 

   more » « less
4. Liquid-like condensates that bind actin promote assembly and bundling of actin filaments

   Walker, C; Chandrasekaran, A; Mansour, D; Graham, K; Torres, A; Wang, L; Lafer, E M; Rangamani, P; Stachowiak, J C (February 2025, Developmental Cell)
5. Actin nano-architecture of phagocytic podosomes

   https://doi.org/10.1038/s41467-022-32038-0  

   Herron, J. Cody; Hu, Shiqiong; Watanabe, Takashi; Nogueira, Ana T.; Liu, Bei; Kern, Megan E.; Aaron, Jesse; Taylor, Aaron; Pablo, Michael; Chew, Teng-Leong; et al (December 2022, Nature Communications)

   Abstract Podosomes are actin-enriched adhesion structures important for multiple cellular processes, including migration, bone remodeling, and phagocytosis. Here, we characterize the structure and organization of phagocytic podosomes using interferometric photoactivated localization microscopy, a super-resolution microscopy technique capable of 15–20 nm resolution, together with structured illumination microscopy and localization-based super-resolution microscopy. Phagocytic podosomes are observed during frustrated phagocytosis, a model in which cells attempt to engulf micropatterned IgG antibodies. For circular patterns, this results in regular arrays of podosomes with well-defined geometry. Using persistent homology, we develop a pipeline for semi-automatic identification and measurement of podosome features. These studies reveal an hourglass shape of the podosome actin core, a protruding knob at the bottom of the core, and two actin networks extending from the core. Additionally, the distributions of paxillin, talin, myosin II, α-actinin, cortactin, and microtubules relative to actin are characterized. 

   more » « less