Phospho-PAK4/PAK5/PAK6 (S474/S560/S602) Recombinant Monoclonal Antibody

The p21-activated kinases PAK4, PAK5, and PAK6 belong to the group II PAK family and serve as critical effectors of Rho GTPases, orchestrating cytoskeletal dynamics, cell migration, and survival signaling pathways. Phosphorylation at the activation loop sites S474, S560, and S602 on PAK4, PAK5, and PAK6 respectively marks the catalytically active state of these kinases, making detection of these phospho-epitopes essential for researchers investigating oncogenic signaling, neuronal development, and cellular stress responses.

This recombinant monoclonal antibody, clone 2D1, offers the reproducibility and sequence-defined consistency that phospho-specific detection demands. Because recombinant production eliminates the batch variability inherent to traditional hybridoma methods, researchers can confidently compare phosphorylation states across longitudinal studies without concerns about antibody drift affecting quantitative assessments.

Validation in Western blot applications demonstrates robust performance in 293 cell lysates, where treatment with the phosphatase inhibitor Calyculin A enables clear visualization of phosphorylated PAK isoforms. The observed bands at approximately 75 and 80 kDa align with the predicted molecular weights for PAK5 and PAK6, while the 64 kDa PAK4 band may require optimization of treatment conditions for detection in this cell system. Immunofluorescence studies in HepG2 cells following Calyculin A treatment confirm the antibody's utility for spatial localization of activated PAK kinases within cellular compartments, providing researchers flexibility to move between biochemical and imaging-based approaches.

Whether investigating PAK-mediated cytoskeletal remodeling, exploring kinase activation in cancer models, or characterizing upstream regulatory mechanisms, this antibody delivers the phospho-specificity and experimental versatility needed for rigorous cell biology research.