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.

CDK5 S142-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.

CDK5 S142-p
Phosphatases, in vitro:
CDC14A S142-p
PTEN S601-p
Putative upstream phosphatases:
CDC14A S142-p
Regulatory protein:
PRP4 S337-p
BI2536 S134-p , S141-p , S142-p
CXCL12 S142-p
ischemia T346-p , S601-p
metastatic potential T335-p , S337-p , S339-p , S341-p , S342-p , T343-p
MLN8054 T335-p , S337-p
nocodazole S141-p , S142-p