ERK1/2 phosphorylates MSK1

MSK1 (Ribosomal protein S6 kinase alpha-5) is a serine/threonine kinase that is localised in the nucleus. It contains two protein kinase domains in a single polypeptide. It can be activated 5-fold by ERK1/2 through phosphorylation at four key residues.MSK1（核糖体蛋白S6激酶α-5）是一种定位于细胞核的丝氨酸/苏氨酸激酶。该激酶在其单个多肽链上含有两个蛋白激酶结构域。通过在四个关键残基上的磷酸化，ERK1/2能够将其激活5倍。