MBPK-1
Source: Bovine kidney.
Purity: > 90% by SDS-PAGE, apparent Mr ~ 40-kDa.
Supplied: 100 ng in 50 μl 50 mM Tris-HCl pH 7.0 buffer containing 14 mM β-mercaptoethanol, 1 mM benzamidine, 0.1 mM phenylmethanesulfonyl fluoride, 1 mM EDTA and 50% glycerol.
Activity: ~ 300 units/mg with myelin basic protein (MBP) as substrate. One unit is the amount of MBPK-1 that incorporates 1 nmol of phosphate into MBP per min. Maintain preparations in aliquots at -70° C. Avoid repeated thawing.
Synonyms: Myelin Basic Protein Kinase 1; MBPK-1
Background: MBPK-1 and MBPK-2 (GLO114-100) are distinct MAP kinase family members. MAP kinases are important components of signal transduction pathways involved in regulating numerous cellular processes including cell growth, division and differentiation. MAP kinases undergo dual phosphorylation on specific tyrosine and threonine sites mapping within a characteristic Thr-Glu-Tyr motif. This dual phosphorylation is catalyzed by MEK in vivo and in vitro.
Furthermore, in vitro, these sites undergo phosphorylation following incubation of purified MAPK with ATP. In contrast to other MAPK’s, MBPK-1 and MBPK-2 do not undergo autophosphorylation on tyrosines and are not inactivated by protein tyrosine phosphatases before or after autophosphorylation of the enzymes. MBPK-1 and MBPK-2 phosphorylate and activate cPK (GLO117-100), a distinct insulin-stimulated protein kinase.