Description
Midkine (MK) is a 15 kDa heparin-binding molecule originally cloned during a search for genes preferentially transcribed during retinoic acid (RA)-induced differentiation. Midkine belongs to a family of neurotrophic and developmentally-regulated heparin-binding molecules consisting of midkine, pleiotrophin (PTN/HBNF/OSF-1/HNGF-8) and the avian midkine homolog, RI-HB (for retinoic acid-inducible heparin-binding protein). Midkine is a highly basic, nonglycosylated polypeptide that contains five intrachain disulfide bonds. The predicted molecular weight is approximately 13.3 kDa, based on a mature peptide length of 118 amino acid residues in the mouse and 121 amino acid residues in the human. Across species, MK shows 87% identity between the human and murine proteins. Between family members, human MK is approximately 50% identical to human PTN, with conservation of all 10 cysteines. Initial structure-function studies indicate that the C-terminal half of MK contains the principal heparin-binding site plus the molecule’s antigenicity and neurite-promoting sequences; while both the C- and N-termini are necessary for the molecule’s neurotrophic effects.
Product Properties
Synonyms |
ARAP, Midgestation and Kidney Protein, Neurite Outgrowth-promoting Factor 2, Neurite Outgrowth-promoting Protein |
Accession |
P21741 |
GeneID |
4192 |
Source |
E.coli-derived Human Midkine, Val21-Asp143. |
Molecular Weight |
Approximately 13.4 kDa. |
AA Sequence |
VAKKKDKVKK GGPGSECAEW AWGPCTPSSK DCGVGFREGT CGAQTQRIRC RVPCNWKKEF GADCKYKFEN WGACDGGTGT KVRQGTLKKA RYNAQCQETI RVTKPCTPKT KAKAKAKKGK GKD |
Tag |
None |
Physical Appearance |
Sterile Filtered White lyophilized (freeze-dried) powder. |
Purity |
> 97 % by SDS-PAGE and HPLC analyses. |
Biological Activity |
The biological activity determined by a chemotaxis bioassay using human neutrophils is in a concentration range of 0.1-10 ng/mL. Fully biologically active when compared to standard. |
Endotoxin |
< 1.0 EU per 1μg of the protein by the LAL method. |
Formulation |
Lyophilized from a 0.2 μm filtered concentrated solution in PBS, pH7.4. |
Reconstitution |
We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Reconstitute in sterile distilled water or aqueous buffer containing 0.1% BSA to a concentration of 0.1-1.0 mg/mL. Stock solutions should be apportioned into working aliquots and stored at ≤ -20℃. Further dilutions should be made in appropriate buffered solutions. |
Shipping and Storage
The products are shipped with ice pack and can be stored at -20℃ to -80℃ for 1 year.
Recommend to aliquot the protein into smaller quantities when first used and avoid repeated freeze-thaw cycles.
Cautions
1. Avoid repeated freeze-thaw cycles.
2. For your safety and health, please wear lab coats and disposable gloves for operation.
3. For research use only!