Table 1. Substrates of p38 group members – kinases.

Substrate	Kinase	Function	References
MAPKAPK2 (MK2)	p38α, p38β, p38γ, p38δ	Activates the kinase substrate	Freshney NW et al., Cell, 1994 4 Rouse J et al., Cell, 1994 3
MAPKAPK3 (MK3)	p38α, p38β, p38γ, p38δ	Activates the kinase substrate	McLaughlin MM et al., J Biol Chem, 1996 54
MNK1/2	p38α	Activates the kinase substrate	Fukunaga R et al., EMBO J, 1997 58 Waskiewicz AJ et al., EMBO J, 1997 57
MSK1/2	p38α	Activates the kinase substrate	Deak M et al., EMBO J, 1998 56 Pierrat B et al., J Biol Chem, 1998 77
PAK6	p38α	Activates the kinase substrate	Kaur R et al., J Biol Chem, 2005 78
PIP4Kb	p38α	Inactivates the kinase substrate	Jones DR et al., Mol Cell, 2006 79
RPAK (MK5)	p38α, p38β	Activates the kinase substrate	New L et al., EMBO J, 1998 55
PKCε	p38α, p38β	Completes cytokinesis	Saurin AT et al., Nat Cell Biol, 2008 80
GSK3β	p38α	Inactivates the kinase substrate, activates Wnt pathway.	Bikkavilli RK et al., J Cell Sci, 2008 60 Thornton TM et al., Science, 2008 59

GSK3β, glycogen synthase kinase 3 beta; MAPKAPK, mitogen-activated protein kinase activated protein kinase; MSK1/2, mitogen- and stress-activated protein kinase; PAK6, p21-activated kinase 6; PIP4Kb, phosphatidylinositol 5 phosphate 4-kinase; PKCε, protein kinase C epsilon type.