ACTA1 Knockout 143B Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population in which the ACTA1 gene has been disrupted in the human 143B osteosarcoma cell line. This heterogeneous pool preserves genetic diversity, enabling loss-of-function studies of alpha-skeletal muscle actin without clonal selection bias. The model provides a robust platform for investigating actin cytoskeleton dynamics, adhesion, and mechanotransduction within a highly tumorigenic bone cancer context.
The 143B cell line is a TK-minus derivative of the HOS osteosarcoma model, characterized by mesenchymal properties, rapid proliferation, and pronounced tumorigenicity in vivo. Its adherent morphology, well-defined stress fibers, and focal adhesions make it ideal for studying actin-dependent processes. The mesenchymal origin ensures that ACTA1 disruption can be interpreted in a cellular environment inherently dependent on actin remodeling for migration, invasion, and mechanical signal transduction.
ACTA1 encodes alpha-skeletal muscle actin, a core component of the sarcomeric thin filament essential for skeletal muscle contraction and universal actin cytoskeleton organization. Its expression is transcriptionally controlled by SRF, MEF2, and MyoD, with upstream regulation by RhoA/ROCK signaling. ACTA1 interacts with tropomyosin, cofilin, and profilin, integrating into the ARP2/3?CWASP-mediated actin polymerization machinery and contractile complexes containing troponin and myosin. Downstream targets include muscle structural genes (MYH, TNNT) and sarcomere proteins (titin, nebulin). Knockout of ACTA1 therefore perturbs actin filament assembly, sarcomeric organization, and the YAP/TAZ mechanotransduction pathway, which depends on actin-mediated nuclear translocation of these transcriptional co-activators.
In 143B osteosarcoma cells, loss of ACTA1 impairs actin stress fiber formation and focal adhesion dynamics, leading to reduced cellular motility and invasive potential??key traits in bone cancer progression. This knockout model enables dissection of how actin isoform usage influences tumor cell plasticity and mechanosensitive signaling. Since YAP/TAZ are frequently hyperactivated in osteosarcoma, the cells serve as a tool to examine whether ACTA1-dependent cytoskeletal integrity modulates the activity of these oncogenic co-factors, linking actin organization to proliferative and metastatic programs.
These polyclonal knockout cells are suitable for a wide range of experimental approaches. Western blotting and RT-qPCR can verify ACTA1 ablation and assess changes in downstream markers such as MYH and TNNT. Immunofluorescence microscopy allows visualization of actin stress fiber collapse and YAP/TAZ subcellular localization. Functional assays including Boyden chamber migration, Matrigel invasion, and cell adhesion quantify altered migratory and invasive behavior. Phospho-signaling analysis permits evaluation of RhoA?CROCK and YAP/TAZ pathway activity. Additionally, the cells can be employed in cytoskeletal drug screening (e.g., cytochalasin D sensitivity) and as a model for studying actin-related muscle disease mechanisms in a non-muscle environment. For further information, please contact Ascent Research.
