RPS6 and psoriasis: Consistent with this, S6K1 (Thr389) is activated in psoriasis lesions [80] and ribosomal protein S6 is activated at multiple phosphorylation sites, with S6 (Ser235/236) more active in the suprabasal epidermis and S6 (Ser240) active throughout the epidermis and basal layer [80, 81].