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Product Includes Quantity (with Count) Solution Color
Phospho-Ezrin (Thr567)/Radixin (Thr564)/Moesin (Thr558) Antibody 3141 30 µl
Kinase Buffer (10X) 9802 15 ml
ATP (10 mM) 9804 1 ml

Product Description

The kit provides a means of performing kinase activity assays with recombinant active human Mst4 kinase. It includes active Mst4 kinase (supplied as a GST fusion protein), a biotinylated peptide substrate and a phospho-serine/threonine antibody for detection of the phosphorylated form of the substrate peptide.

Molecular Formula:

Peptide substrate, Ezrin (Thr567)/Radixin (Thr564)/Moesin (Thr558) Biotinylated Peptide #1344: 1,958 Daltons, GST-Mst4 Kinase: 76 kDa.

Peptide Core Sequence:


Mst kinases, members of the STE20 family of kinases, are upstream activators of MAPK pathways that regulate processes such as apoptosis, morphogenesis and cytoskeletal rearrangements. The amino-terminal kinase domain of Mst is considerably homologous to the kinase domain of yeast STE20 kinase and other p21-activated kinases (1). The carboxy-terminal region of Mst1 and Mst2 contains dimerization and inhibitory domains (1-3). Dimerization and phosphorylation at the activation loop results in translocation of Mst1 from the cytosol to the nucleus (3). Growing evidence indicates that Mst1, Mst2 and Mst3 are activated by apoptotic signals as well as other stress conditions (4-6). Complete activation of Mst1 requires both phosphorylation and caspase-mediated cleavage (4). Sequence alignment of the activation loop of the GCK family indicates that Thr183 of Mst1 and Thr180 of Mst2 are the conserved residues and might be critical for the activity of the kinases. Activated Mst kinases may rely on p38 MAPK and JNK pathways to amplify apoptotic signals (5). Phosphorylation at Ser327 of Mst1, which is close to the caspase-3 recognition site, inhibits caspase-mediated cleavage (4).

1.  Dan, I. et al. (2001) Trends Cell Biol. 11, 220-230.

2.  Creasy, C.L. et al. (1996) J. Biol. Chem. 271, 21049-21053.

3.  Lee, K. and Yonehara, S. (2002) J. Biol. Chem. 277, 12351-12358.

4.  Graves, J.D. et al. (2001) J. Biol. Chem. 276, 14909-14915.

5.  Lee, K. et al. (2001) J. Biol. Chem. 276, 19276-19285.

6.  Graves, J.D. et al. (1998) EMBO J. 17, 2224-2234.

Entrez-Gene Id 51765
Swiss-Prot Acc. Q9P289

Data Sheets & Documentation

For Research Use Only. Not For Use In Diagnostic Procedures.
Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc.
DELFIA is a registered trademark of PerkinElmer, Inc.