PKC, and casein kinases I and II that can phosphorylate and thereby activate CREB/CREM proteins [17]. Serine residue 117 of CREM is one target for activating protein kinases [18]. In the context of T cell biology, T cell receptor (TCR) activation and increased calcium influx, as induced by ionomycine, are alternative pathways that activate protein kinases that phosphorylate CREB/ CREM proteins, such as calcium/calmodulin-dependent kinases (CaMKs). Sera of SLE patients display increased CaMKIV activity, which activates CREMα and leads to transcriptional effects on the IL2 promoter [19].
