RSKL

The RSK-like group, RSKL1 (SgK496) and RSKL2 (SgK269), is a poorly characterized branch of the AGC family whose members retain the RSK-type tandem kinase-domain architecture but show limited similarity elsewhere in sequence. Present knowledge places them in the cytoplasm and nucleus with cell-type-restricted expression patterns; specific substrates and physiological roles remain largely undetermined, though genomic studies have associated the RSKL2 locus with carcinomas of the prostate, colon, and other epithelial tissues, and RSKL2 is reported to reside at epithelial cell-cell junctions. Because natural activators and downstream effectors are unresolved, recombinant RSKL proteins serve mainly in kinase-panel profiling, phosphoproteomic substrate screening, antibody generation, and functional studies aimed at defining this enigmatic AGC branch.