Phospho-p90Rsk/RSK1/RPS6KA1-S363 Rabbit pAb - Q15418

Core Product Specifications and Parameters

Biological Background: Ribosomal Protein S6 Kinase Alpha-1 (RSK1) Function and Localization

• Ribosomal protein S6 kinase alpha-1 (RSK1, p90RSK1) is a serine/threonine kinase encoded by the RPS6KA1 gene, acting downstream of the ERK1/2 MAPK pathway to integrate mitogenic and stress signals.
• RSK1 phosphorylates the transcription factor CREB1 in response to EGF, contributing to immediate-early gene expression and cell proliferation. Related references: PMID:18508509 PMID:18813292
• It activates the NR4A1/NUR77 and ETV1/ER81 transcription factors as well as the CREBBP coactivator, thereby modulating transcriptional programs. Related references: PMID:12213813 PMID:16223362
• In the cytoplasm, RSK1 regulates cap-dependent translation by phosphorylating RPS6 and EIF4B, enhancing the assembly of the translation pre-initiation complex. Related references: PMID:17360704 PMID:16763566
• RSK1 is a critical node in the mTOR signaling network: it directly phosphorylates TSC2 and RPTOR to control mTORC1 activity, and contributes to feedback regulation by targeting DEPTOR. Related references: PMID:15342917 PMID:22017876
• The kinase promotes cell survival by phosphorylating the pro-apoptotic proteins BAD and DAPK1, inhibiting their apoptotic functions. Related references: PMID:10679322 PMID:16213824
• RSK1 regulates cell cycle progression by phosphorylating the CDK inhibitor CDKN1B (p27Kip1), leading to its cytoplasmic sequestration via 14-3-3 binding and removal of G1 blockade. Related references: PMID:18508509 PMID:18813292
• Additionally, RSK1 controls cell migration through phosphorylation of EPHA2 at Ser-897, influencing the RPS6KA-EPHA2 signaling axis. Related references: PMID:26158630
• The protein localizes to both nucleus and cytoplasm, consistent with its multi-functional roles in signaling and gene regulation. Key post-translational modifications include multiple phosphorylation events essential for its activation (UniProt keywords: Phosphoprotein, Serine/threonine-protein kinase, Stress response).

Experimental Guidance and Technical Tips

• The immunogen is a synthetic phosphorylated peptide corresponding to residues around Ser363 of human RSK1; this site is a known regulatory phosphorylation target in the kinase linker region. For Western blotting, verify the band at ~83 kDa under appropriate stimulation conditions (e.g., serum or EGF treatment) and confirm phospho-specificity by phosphatase treatment or competition with non-phosphorylated peptide.
• Reported applications include WB, IP, and ELISA. When performing immunoprecipitation, optimize antibody concentration and consider using fresh lysates with phosphatase inhibitors to preserve phosphorylation.
• The antibody shows cross-reactivity with rat RSK1. For applications in rat samples, validate the detection of the homologous phospho-epitope in your experimental system.
• Since RSK1 activation depends on the ERK pathway, include appropriate positive controls (e.g., PMA- or EGF-stimulated cell lines) and monitor total RSK1 levels to normalize phospho-signals.

CamelBio: Your One-Stop Sourcing Bridge

CamelBio supports diagnostic developers and research teams in accelerating projects from concept to clinic. For signal transduction studies involving RSK1 and related kinases, we can source validated antibody pairs, optimized monoclonal/polyclonal antibodies, and bulk ancillary reagents. Our one-stop supply model covers hard-to-find phospho-specific antibodies and custom development needs, ensuring reliable access to critical raw materials for your IVD workflows.