Recombinant human Muscle, skeletal receptor tyrosine-protein kinase (MUSK), protein kinase domain, 10 µg

Background: MuSK is a receptor tyrosine kinase that plays an important role in the formation and stabilization of neuromuscular junctions (NMJs) expressed in mammalian tissues other than skeletal muscle, including excitatory neurons in the central nervous system and sperm. The extracellular region comprises three immunoglobulin-like domains and a cysteine-rich domain. The cytoplasmic juxtamembrane segment of MuSK (~ 40 residues) links the transmembrane helix to the tyrosine kinase domain.Upon interaction of agrin, derived from motor neurons, to the transmembrane protein LRP4 induces a conformational change in LRP4 that enhances the interaction between LRP4 and MuSK and facilitates MuSK trans-phosphorylation. In addition to this, MuSK requires a cytoplasmic protein, Dok7, for activation. Dok7 binds directly to the juxtamembrane region of MuSK juxtaposes two MuSK kinase domains for trans-phosphorylation of the three tyrosine residues. The MuSK complex has an intrinsic capacity to organise acetylcholine receptors (AChR) clusters and is essential for targeting AChRs, acetylcholinesterase and a variety of other postsynaptic proteins to the developing synapse.

human MUSK (protein kinase domian, amino acids R529-V869 as in GenBank entry NM_005592), N-terminally fused to GST-HIS6-Thrombin cleavage site

Theoretical MW : 68.4 kDa (fusion proteins)
Expression system: Sf9 cells
Purification: One-step affinity purification using glutathione agarose
Activation: Incubation with 0.1 mM ATP, followed by (NH4)2SO4 precipitation
Storage buffer: 50 mM Tris-HCl, pH 8.0; 100 mM NaCl, 5 mM DTT, 20% glycerol
Protein concentration: 0.159 mg/ml (Bradford method using BSA as standard protein)
Method for determination of Km value & specific activity: Filter binding assay MAFC membrane
Specific activity : 19,000 pmol/mg x min

Entrez Gene ID: 4593
UniProt KB: 015146

Ordering information: shipped on dry ice

Product specific literature

Ghazanfari N1, Fernandez KJ, Murata Y, Morsch M, Ngo ST, Reddel SW, Noakes PG, Phillips WD. (2011) Muscle specific kinase: organiser of synaptic membrane domains.Int J Biochem Cell Biol. 2011 Mar;43(3):295-8

Hubbard SR1, Gnanasambandan K. (2013) Structure and activation of MuSK, a receptor tyrosine kinase central to neuromuscular junction formation.Biochim Biophys Acta. 2013 Oct;1834(10):2166-9.