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.

ERK1 T148-p , S306-p , S341-p
ERK2 T148-p , S306-p , S341-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.

ERK2 S341-p
Regulatory protein:
BRAF T148-p , S306-p , S341-p
HER2 T148-p , S306-p , S341-p
MEK1 T148-p , S306-p , S341-p
PRP4 S306-p
Treatment:
CGP57380 S341-p
ionizing_radiation S69-p
PD0325901 T148-p , S306-p , S341-p
SCH772984 S341-p
Trametinib T148-p , S306-p , S341-p
UV S244-p