Multiple phosphorylation events control mitotic degradation of the muscle transcription factor Myf5

BMC Biochemistry

Table 1 List of kinase and phosphatase inhibitors tested in Xenopus egg extracts for their potential effect on Myf5 degradation These inhibitors were purchased from Sigma-Aldrich, stock solutions were prepared in ethanol or DMSO, following the furnisher instructions.

Inhibitor	Action	Concentrations tested	Effect on Myf5 phosphorylation status (*)	References
Indirubin-3'-oxime	GSK3β and CDK5 inhibitor	10¹ to 100 μM	Partial inhibition	[54, 55]
Roscovitine	CDK/cyclin inhibitor	100 μM²	Partial inhibition	[56–58]
Staurosporine	Broad spectrum kinase inhibitor (among which: PKA, PKG, CaMK, MLCK, PKC)	1¹ to 10 μM	Strong inhibition	[59, 60]
U0126	MEK1/2 inhibitor	50¹ to 100 μM	Partial inhibition	[61, 62]
GF109203X	PKC inhibitor	5¹ to 50 μM	Partial inhibition	[63, 64]
Cyclosporin A	Calcineurin inhibitor	1¹ to 10 μg/ml	No effect	[65, 66]
Microcystin LR	Broad spectrum phosphatase inhibitor	1 μM	Hyperphosphorylation	[42, 67]

¹ Usual concentration for treatment of cell cultures
² Efficiency of this concentration was tested by measuring H1 Kinase activity after treatment.
(*) as judged by electrophoretic migration pattern

ISSN: 1471-2091