Human MUSK ELISA Kit (HUEB0931)- High Sensitivity

Product Name:	Human Muscle, skeletal receptor tyrosine-protein kinase (MUSK) ELISA Kit
SKU:	HUEB0931
Size:	96T
Target:	Human Muscle, skeletal receptor tyrosine-protein kinase (MUSK)
Synonyms:	Muscle-specific tyrosine-protein kinase receptor, MuSK
Assay Type:	Sandwich
Detection Method:	ELISA
Reactivity:	Human
Detection Range:	0.156-10ng/mL
Sensitivity:	0.045ng/mL

Intra CV:

3.8%

Inter CV:

7.4%

Linearity:

Sample	1:2	1:4	1:8	1:16
Serum(N=5)	100-112%	100-109%	103-113%	98-110%
EDTA Plasma(N=5)	104-113%	105-115%	101-110%	91-101%
Heparin Plasma(N=5)	106-116%	94-104%	101-111%	92-102%

Recovery:

Sample Type	Average(%)	Recovery Range(%)
Serum	97	91-103
Plasma	99	93-105

Function:

Receptor tyrosine kinase which plays a central role in the formation and the maintenance of the neuromuscular junction (NMJ), the synapse between the motor neuron and the skeletal muscle (PubMed:25537362). Recruitment of AGRIN by LRP4 to the MUSK signaling complex induces phosphorylation and activation of MUSK, the kinase of the complex. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. May regulate AChR phosphorylation and clustering through activation of ABL1 and Src family kinases which in turn regulate MUSK. DVL1 and PAK1 that form a ternary complex with MUSK are also important for MUSK-dependent regulation of AChR clustering. May positively regulate Rho family GTPases through FNTA. Mediates the phosphorylation of FNTA which promotes prenylation, recruitment to membranes and activation of RAC1 a regulator of the actin cytoskeleton and of gene expression. Other effectors of the MUSK signaling include DNAJA3 which functions downstream of MUSK. May also play a role within the central nervous system by mediating cholinergic responses, synaptic plasticity and memory formation.

Uniprot:	O15146
Sample Type:	Serum, plasma, tissue homogenates, cell culture supernates and other biological fluids
Specificity:	Natural and recombinant human Muscle, skeletal receptor tyrosine-protein kinase
Sub Unit:	Monomer (By similarity). Homodimer (Probable). Interacts with LRP4; the heterodimer forms an AGRIN receptor complex that binds AGRIN resulting in activation of MUSK (By similarity). Forms a heterotetramer composed of 2 DOK7 and 2 MUSK molecules which facilitates MUSK trans-autophosphorylation on tyrosine residue and activation. Interacts (via cytoplasmic part) with DOK7 (via IRS-type PTB domain); requires MUSK phosphorylation. Interacts with DVL1 (via DEP domain); the interaction is direct and mediates the formation of a DVL1, MUSK and PAK1 ternary complex involved in AChR clustering (By similarity). Interacts with PDZRN3; this interaction is enhanced by agrin (By similarity). Interacts with FNTA; the interaction is direct and mediates AGRIN-induced phosphorylation and activation of FNTA (By similarity). Interacts with CSNK2B; mediates regulation by CK2 (By similarity). Interacts (via the cytoplasmic domain) with DNAJA3 (By similarity). Interacts with NSF; may regulate MUSK endocytosis and activity (By similarity). Interacts with CAV3; may regulate MUSK signaling (By similarity). Interacts with RNF31.
Research Area:	Signal Transduction
Subcellular Location:	Cell junction Synapse Postsynaptic cell membrane Single-pass type I membrane protein Colocalizes with acetylcholine receptors (AChR) to the postsynaptic cell membrane of the neuromuscular junction.
Storage:	Please see kit components below for exact storage details
Note:	For research use only

UniProt Protein Function:	MUSK: a receptor tyrosine kinase that is essential for the establishment and maintenance of the neuromuscular junction (NMJ). Its activation by agrin, a neuronally derived heparan-sulfate proteoglycan, and the agrin receptor (LRP4), leads to clustering of acetylcholine receptors on the postsynaptic side of the NMJ. Its activation by agrin requires Dok7, which interacts with the cytoplasmic portion of MuSK and activates its tyrosine kinase activity.
UniProt Protein Details:	Protein type:Protein kinase, tyrosine (receptor); Membrane protein, integral; Protein kinase, TK; Kinase, protein; EC 2.7.10.1; TK group; Musk family Chromosomal Location of Human Ortholog: 9q31.3-q32 Cellular Component: postsynaptic membrane; integral to plasma membrane; neuromuscular junction; cell junction; receptor complex Molecular Function:protein binding; protein-tyrosine kinase activity; transmembrane receptor protein tyrosine kinase activity; ATP binding Biological Process: extracellular matrix organization and biogenesis; peptidyl-tyrosine phosphorylation; regulation of transcription, DNA-dependent; positive regulation of neuron apoptosis; protein amino acid autophosphorylation; multicellular organismal development; regulation of synaptic growth at neuromuscular junction; positive regulation of protein amino acid phosphorylation; cell differentiation; transmembrane receptor protein tyrosine kinase signaling pathway; memory; neuromuscular junction development Disease: Myasthenic Syndrome, Congenital, 9, Associated With Acetylcholine Receptor Deficiency; Fetal Akinesia Deformation Sequence
NCBI Summary:	This gene encodes a muscle-specific tyrosine kinase receptor. The encoded protein may play a role in clustering of the acetylcholine receptor in the postsynaptic neuromuscular junction. Mutations in this gene have been associated with congenital myasthenic syndrome. Alternatively spliced transcript variants have been described.[provided by RefSeq, Oct 2009]
UniProt Code:	O15146
NCBI GenInfo Identifier:	50400806
NCBI Gene ID:	4593
NCBI Accession:	O15146.1
UniProt Secondary Accession:	O15146,Q32MJ8, Q32MJ9, Q5VZW7, Q5VZW8,
UniProt Related Accession:	O15146
Molecular Weight:	86,425 Da
NCBI Full Name:	Muscle, skeletal receptor tyrosine-protein kinase
NCBI Synonym Full Names:	muscle, skeletal, receptor tyrosine kinase
NCBI Official Symbol:	MUSK
NCBI Protein Information:	muscle, skeletal receptor tyrosine-protein kinase; muscle-specific kinase receptor; muscle-specific tyrosine-protein kinase receptor
UniProt Protein Name:	Muscle, skeletal receptor tyrosine-protein kinase
UniProt Synonym Protein Names:	Muscle-specific tyrosine-protein kinase receptor; MuSK; Muscle-specific kinase receptor
Protein Family:	Muskelin
UniProt Gene Name:	MUSK
UniProt Entry Name:	MUSK_HUMAN

Component	Quantity (96 Assays)	Storage
ELISA Microplate (Dismountable)	8×12 strips	-20°C
Lyophilized Standard	2	-20°C
Sample Diluent	20ml	-20°C
Assay Diluent A	10mL	-20°C
Assay Diluent B	10mL	-20°C
Detection Reagent A	120µL	-20°C
Detection Reagent B	120µL	-20°C
Wash Buffer	30mL	4°C
Substrate	10mL	4°C
Stop Solution	10mL	4°C
Plate Sealer	5	-

Other materials and equipment required:

Microplate reader with 450 nm wavelength filter
Multichannel Pipette, Pipette, microcentrifuge tubes and disposable pipette tips
Incubator
Deionized or distilled water
Absorbent paper
Buffer resevoir

*Note: The below protocol is a sample protocol. Protocols are specific to each batch/lot. For the correct instructions please follow the protocol included in your kit.

Allow all reagents to reach room temperature (Please do not dissolve the reagents at 37°C directly). All the reagents should be mixed thoroughly by gently swirling before pipetting. Avoid foaming. Keep appropriate numbers of strips for 1 experiment and remove extra strips from microtiter plate. Removed strips should be resealed and stored at -20°C until the kits expiry date. Prepare all reagents, working standards and samples as directed in the previous sections. Please predict the concentration before assaying. If values for these are not within the range of the standard curve, users must determine the optimal sample dilutions for their experiments. We recommend running all samples in duplicate.

Step
1.	Add Sample: Add 100µL of Standard, Blank, or Sample per well. The blank well is added with Sample diluent. Solutions are added to the bottom of micro ELISA plate well, avoid inside wall touching and foaming as possible. Mix it gently. Cover the plate with sealer we provided. Incubate for 120 minutes at 37°C.
2.	Remove the liquid from each well, don't wash. Add 100µL of Detection Reagent A working solution to each well. Cover with the Plate sealer. Gently tap the plate to ensure thorough mixing. Incubate for 1 hour at 37°C. Note: if Detection Reagent A appears cloudy warm to room temperature until solution is uniform.
3.	Aspirate each well and wash, repeating the process three times. Wash by filling each well with Wash Buffer (approximately 400µL) (a squirt bottle, multi-channel pipette,manifold dispenser or automated washer are needed). Complete removal of liquid at each step is essential. After the last wash, completely remove remaining Wash Buffer by aspirating or decanting. Invert the plate and pat it against thick clean absorbent paper.
4.	Add 100µL of Detection Reagent B working solution to each well. Cover with the Plate sealer. Incubate for 60 minutes at 37°C.
5.	Repeat the wash process for five times as conducted in step 3.
6.	Add 90µL of Substrate Solution to each well. Cover with a new Plate sealer and incubate for 10-20 minutes at 37°C. Protect the plate from light. The reaction time can be shortened or extended according to the actual color change, but this should not exceed more than 30 minutes. When apparent gradient appears in standard wells, user should terminatethe reaction.
7.	Add 50µL of Stop Solution to each well. If color change does not appear uniform, gently tap the plate to ensure thorough mixing.
8.	Determine the optical density (OD value) of each well at once, using a micro-plate reader set to 450 nm. User should open the micro-plate reader in advance, preheat the instrument, and set the testing parameters.
9.	After experiment, store all reagents according to the specified storage temperature respectively until their expiry.

When carrying out an ELISA assay it is important to prepare your samples in order to achieve the best possible results. Below we have a list of procedures for the preparation of samples for different sample types.

Sample Type	Protocol
Serum	If using serum separator tubes, allow samples to clot for 30 minutes at room temperature. Centrifuge for 10 minutes at 1,000x g. Collect the serum fraction and assay promptly or aliquot and store the samples at -80°C. Avoid multiple freeze-thaw cycles. If serum separator tubes are not being used, allow samples to clot overnight at 2-8°C. Centrifuge for 10 minutes at 1,000x g. Remove serum and assay promptly or aliquot and store the samples at -80°C. Avoid multiple freeze-thaw cycles.
Plasma	Collect plasma using EDTA or heparin as an anticoagulant. Centrifuge samples at 4°C for 15 mins at 1000 × g within 30 mins of collection. Collect the plasma fraction and assay promptly or aliquot and store the samples at -80°C. Avoid multiple freeze-thaw cycles. Note: Over haemolysed samples are not suitable for use with this kit.
Urine & Cerebrospinal Fluid	Collect the urine (mid-stream) in a sterile container, centrifuge for 20 mins at 2000-3000 rpm. Remove supernatant and assay immediately. If any precipitation is detected, repeat the centrifugation step. A similar protocol can be used for cerebrospinal fluid.
Cell culture supernatant	Collect the cell culture media by pipette, followed by centrifugation at 4°C for 20 mins at 1500 rpm. Collect the clear supernatant and assay immediately.
Cell lysates	Solubilize cells in lysis buffer and allow to sit on ice for 30 minutes. Centrifuge tubes at 14,000 x g for 5 minutes to remove insoluble material. Aliquot the supernatant into a new tube and discard the remaining whole cell extract. Quantify total protein concentration using a total protein assay. Assay immediately or aliquot and store at ≤ -20 °C.
Tissue homogenates	The preparation of tissue homogenates will vary depending upon tissue type. Rinse tissue with 1X PBS to remove excess blood & homogenize in 20ml of 1X PBS (including protease inhibitors) and store overnight at ≤ -20°C. Two freeze-thaw cycles are required to break the cell membranes. To further disrupt the cell membranes you can sonicate the samples. Centrifuge homogenates for 5 mins at 5000xg. Remove the supernatant and assay immediately or aliquot and store at -20°C or -80°C.
Tissue lysates	Rinse tissue with PBS, cut into 1-2 mm pieces, and homogenize with a tissue homogenizer in PBS. Add an equal volume of RIPA buffer containing protease inhibitors and lyse tissues at room temperature for 30 minutes with gentle agitation. Centrifuge to remove debris. Quantify total protein concentration using a total protein assay. Assay immediately or aliquot and store at ≤ -20 °C.
Breast Milk	Collect milk samples and centrifuge at 10,000 x g for 60 min at 4°C. Aliquot the supernatant and assay. For long term use, store samples at -80°C. Minimize freeze/thaw cycles.

ELISA

Human MUSK ELISA Kit

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