Ribosomal protein S6 kinase alpha-4 (RPS6KA4)

Ribosomal protein S6 kinase alpha-4 (RPS6KA4), also known as mitogen- and stress-activated protein kinase 2 (MSK2), is a serine/threonine-protein kinase in the RSK family. It contains two distinct kinase domains and is activated by MAPK pathways in response to growth factors and cellular stress. RPS6KA4 phosphorylates downstream effectors including transcription factors (CREB1, ATF1, c-Fos, c-Jun) and histones (notably histone H3), regulating immediate early gene transcription, inflammatory responses, and cell growth. It plays roles in cancer, inflammation, and other conditions with abnormal cell proliferation or stress response. Although no selective therapeutic drugs currently target RPS6KA4, kinase inhibitors that impact S6K pathways are under investigation for cancer and metabolic diseases[1][5][6][9].

Other names

RPS6KA4MSK2 (mitogen- and stress-activated protein kinase 2)MAPK-activated protein kinase-2S6K-alpha-4

Inhibition of serine/threonine kinase activity, leading to reduced phosphorylation of substrates involved in transcription and cell growth; Down-regulation of mTOR/S6K signaling may suppress cell proliferation and protein synthesis.