Kinase, in vitro: 

An enzyme-substrate reaction that occurs in non-living experimental conditions such as a test tube. For example, a purified enzyme is reacted with a substrate protein or mixture of proteins or peptides.

p90RSK S205-p
 Putative in vivo kinases: 

An enzyme-substrate reaction that occurs within living cells; includes cultured cells, ex vivo samples, and intact organisms. In the case of kinases, the large number of protein kinases in intact cells makes exact identification of the responsible kinase challenging.

CDK2 S203-p
p90RSK S205-p
Regulatory protein:
PRP4 S203-p
Treatment:
BI2536 S43-p
EGF Y195-p
H2O2 S205-p
interstitial flow S205-p
ionizing_radiation S203-p , S206-p
nocodazole S36-p , S154-p , S203-p
U0126 Y195-p
UV S203-p , S206-p