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The Mitogen-activated Protein Kinase Phosphatase-3 N-terminal Noncatalytic Region Is Responsible for Tight Substrate Binding and Enzymatic Specificity

1998; Elsevier BV; Volume: 273; Issue: 15 Linguagem: Inglês

10.1074/jbc.273.15.9323

1083-351X

Marco Muda, Aspasia Theodosiou, Corine Gilliéron, Anna L. Smith, Christian Chabert, Montserrat Camps, Ursula Boschert, Nanda R. Rodrigues, Kay E. Davies, Alan Ashworth, Steve Arkinstall,

Cancer Mechanisms and Therapy

We have reported recently that the dual specificity mitogen-activated protein kinase phosphatase-3 (MKP-3) elicits highly selective inactivation of the extracellular signal-regulated kinase (ERK) class of mitogen-activated protein (MAP) kinases (Muda, M., Theodosiou, A., Rodrigues, N., Boschert, U., Camps, M., Gillieron, C., Davies, K., Ashworth, A., and Arkinstall, S. (1996) J. Biol. Chem. 271, 27205–27208). We now show that MKP-3 enzymatic specificity is paralleled by tight binding to both ERK1 and ERK2 while, in contrast, little or no interaction with either c-Jun N-terminal kinase/stress activated protein kinase (JNK/SAPK) or p38 MAP kinases was detected. Further study revealed that the N-terminal noncatalytic domain of MKP-3 (MKP-3ΔC) binds both ERK1 and ERK2, while the C-terminal MKP-3 catalytic core (MKP-3ΔN) fails to precipitate either of these MAP kinases. A chimera consisting of the N-terminal half of MKP-3 with the C-terminal catalytic core of M3-6 also bound tightly to ERK1 but not to JNK3/SAPKβ. Consistent with a role for N-terminal binding in determining MKP-3 specificity, at least 10-fold higher concentrations of purified MKP-3ΔN than full-length MKP-3 is required to inhibit ERK2 activity. In contrast, both MKP-3ΔN and full-length MKP-3 inactivate JNK/SAPK and p38 MAP kinases at similarly high concentrations. Also, a chimera of the M3-6 N terminus with the MKP-3 catalytic core which fails to bind ERK elicits non selective inactivation of ERK1 and JNK3/SAPKβ. Together, these observations suggest that the physiological specificity of MKP-3 for inactivation of ERK family MAP kinases reflects tight substrate binding by its N-terminal domain.