Ribosomal protein S6 kinases (RSK) are a family of broadly expressed serine/threonine kinases activated in response to mitogenic stimuli, including tumor-promoting growth factors and phorbol esters. RSKs are positioned downstream of the Raf-MEK-ERK signal transduction pathway, and are directly phosphorylated by ERK1 and ERK2extracellular kinases. Active RSKs appear to play a significant role in transcriptional regulation, translocation to the nucleus, and phosphorylation of c-Fos and CREBs.

Current models suggest that RSK activation requires a binding of active ERK1/2 to a docking site at the carboxyl end of RSK. ERK moored to RSK1 phosphorylate at several sites, including the CTD activation loop (carboxyl-terminal kinase domain). The CTD autophosphorylates Serine 380, a site in the central hydrophobic region.

The AlphaLISA™ SureFire® Ultra™ p-RSK1 (Ser380) assay is a sandwich immunoassay for the quantitative detection of phospho-RSK1 (phosphorylated on Ser380) in cellular lysates, using Alpha Technology.

Formats:

• The HV (high volume) kit contains reagents to run 100 wells in 96-well format, using a 60 μL reaction volume.
• The 500-point kit contains enough reagents to run 500 wells in 384-well format, using a 20 μL reaction volume.
• The 10,000-point kit contains enough reagents to run 10,000 wells in 384-well format, using a 20 μL reaction volume.
• The 50,000-point kit contains enough reagents to run 50,000 wells in 384-well format, using a 20 μL reaction volume.

AlphaLISA SureFire Ultra kits are compatible with:

• Cell and tissue lysates
• Antibody modulators
• Biotherapeutic antibodies

Alpha SureFire kits can be used for:

• Cellular kinase assays
• Receptor activation studies
• Screening