Product Name: RSK1-pS221
Product Number: AB-PK804
Size: 25 µg      Price:89.00
      $US
Target Full Name: Ribosomal S6 protein-serine kinase 1; Ribosomal protein S6 kinase alpha 2

Target Alias: 90 kDa ribosomal protein S6 kinase 1; HU-1; Kinase p90RSK1; KS6A1; KS6AA; MAPKAPK1A; P90RSK1; RPS6KA1; S6K-alpha 1; CCDS284.1; ENSG00000117676

Product Type Specific: Protein kinase phosphosite-specific antibody

Antibody Code: PK804

Antibody Target Type: Phosphosite-specific

Antibody Phosphosite: S221

Protein UniProt: Q15418

Protein SigNET: Q15418

Antibody Type: Polyclonal

Antibody Host Species: Rabbit

Antibody Immunogen Source: Human RSK1 (RPS6KA1, p90RSK) sequence peptide Cat. No.: PE-04AGF99

Antibody Immunogen Sequence: KAY(pS)FCG(bA)C

Antibody Immunogen Description: Corresponds to amino acid residues K218 to G224; In the protein kinase catalytic domain activation T loop region between subdomains VII and VIII.

Production Method: The immunizing peptide was produced by solid phase synthesis on a multipep peptide synthesizer and purified by reverse-phase hplc chromatography. Purity was assessed by analytical hplc and the amino acid sequence confirmed by mass spectrometry analysis. This peptide was coupled to KLH prior to immunization into rabbits. New Zealand White rabbits were subcutaneously injected with KLH-coupled immunizing peptide every 4 weeks for 4 months. The sera from these animals was applied onto an agarose column to which the immunogen peptide was thio-linked. Antibody was eluted from the column with 0.1 M glycine, pH 2.5. Subsequently, the antibody solution was neutralized to pH 7.0 with saturated Tris.This antibody was also subject to negative purification over phosphotyrosine-agarose.

Antibody Modification: Unconjugated. Contact KInexus if you are interest in having the antibody biotinylated or coupled with fluorescent dyes.

Antibody Concentration: 1 mg/ml

Storage Buffer: Phosphate buffered saline pH 7.4, 0.05% Thimerasol

Storage Conditions: For long term storage, keep frozen at -40°C or lower. Stock solution can be kept at +4°C for more than 3 months. Avoid repeated freeze-thaw cycles.

Product Use: Western blotting | Antibody microarray

Antibody Dilution Recommended: 2 µg/ml for immunoblotting

Antibody Potency: Very strong immunoreactivity of a target-sized protein by Western blotting in HepG2 and Jurkat cells.

Antibody Species Reactivity: Human

Antibody Positive Control: The observed molecular mass of the processed target protein on SDS-PAGE gels is reported to be around 82-92 kDa.
Antibody Specificity: High-very high

Antibody Cross Reactivity: Almost no significant cross-reactivities detected in HepG2 and Jurkat cells.

Related Product 1: RSK1-pS221 blocking peptide

Related Product 2: RSK1-CT pan-specific antibody (Cat. No.: AB-NK164-3)

Related Product 3: RSK1-pS380 phosphosite-specific antibody (Cat. No.: AB-PK805)

Related Product 4: RSK1-pT573 phosphosite-specific antibody (Cat. No.: AB-PK806)

Related Product 5: RSK1-pY220+pS221 phosphosite-specific antibody (Cat. No.: AB-PK807)

Related Product 6: RSKSubtide - RSK1_d1 (RPS6KA2) protein kinase substrate peptide
Related Product 7: RPS6 (230-238) KinSub - 40S ribosomal protein S6 (K230-R238, human) peptide; p70S6K protein kinase substrate peptide

Related Product 8: RPS6 (230-239) KinSub - 40S ribosomal protein S6 (K230-A239, human) peptide; RSK protein kinase substrate peptide

Scientific Background: RSK1 (RPS6KA1) is a protein-serine/threonine kinase of the AGC group and RSK family, which features two kinase catalytic domains on the same polypeptide chain. This kinase is highly expressed and widely distributed in most tested human tissues. RSK1 transcript is present in lymphocytes, skeletal muscle, liver, and adipose tissue. RSK1 is activated by phosphorylation at S363, S380 and T573. Phosphorylation at S221 by PDK1 is required for increased phosphotransferase activity, but is insufficient by itself. Phosphorylation at S154 induces interaction with 14-3-3 and inhibits catalytic activity. RSKs are implicated in the activation of the mitogen-activated kinase (MAPK) cascade and the stimulation of cell proliferation and differentiation. RSK1 forms a complex with either ERK1 or ERK2 in quiescent cells, and phosphorylation of S732 in response to mitogenic stimulation of cells permits dissociation of RSK-ERK complexes. RSK1 is known phosphorylates various substrates, including members of the mitogen-activated kinase (MAPK) signalling pathway -- a pro-growth/anti-apoptotic pathway, as it will activate CREB, which in turn will upregulate expression of cyclin-D and c-Myc. Activation of this pathway is common in various types of tumours. RSK1 may be a tumour requiring protein (TRP). The active form of the protein kinase normally acts to promote tumour cell proliferation. Abnormal activation of RSK1 expression has been linked to many human diseases, including breast and prostate cancers. Inhibition of RSK signalling enhances the effects of enzalutamide prostate cancer therapy.
Figure 1. Dot blotting RSK1-pS221 antibody with recombinant purified proteins.


Figure 2. Epitope mapping of RSK1-pS221 antibody with similar phosphopeptides on dot blots.


Figure 3. Identification of phosphosites related to RSK1-pS221.