Description
Melanoma Inhibiting Activity (MIA), also known as cartilage-derived retinoic acid-sensitive protein (CD-RAP), is an approximately 11-15 kDa protein that is secreted as a noncovalent homodimer and is structurally related to OTOR/Otoraplin and MIA-2. Mature human MIA contains a SH3 domain and shares 90% and 92% amino acid sequence identity with mouse and rat MIA, respectively. Alternative splicing generates a short isoform that lacks the SH3 domain. MIA is widely expressed in developing and regenerating cartilage and in the endothelium and parenchyma of developing lungs. MIA disrupts cellular interactions with the extracellular matrix by binding to Integrins alpha 4 beta 1 and alpha 5 beta 1. It competes with Fibronectin fragments for Integrin binding and interferes with Integrin signaling. It also functions as a chemoattractant for mesenchymal stem cells and enhances their BMP-2 and TGF-beta 3 induced differentiation into chondrocytes [tscheud]. MIA-deficient mice exhibit delayed chondrocyte differentiation but enhanced chondrocyte proliferation and cartilage repair. MIA is up-regulated in several cancers including malignant melanoma, lung adenoma, metastatic oral squamous cell carcinoma, neurofibromatosis type 1 (NF-1)-related tumors, and pancreatic cancer. It is selectively secreted and internalized from the trailing pole of migrating cells. This polarization reduces cellular attachment to the matrix at the trailing pole and contributes to directional tumor cell migration.
Molecular Weight
Approximately 12.1 kDa.
AA sequence
GPMPKLADRK LCADQECSHP ISMAVALQDY MAPDCRFLTI HRGQVVYVFS KLKGRGRLFW GGSVQGDYYG DLAARLGYFP SSIVREDQTL KPGKVDVKTD KWDFYCQ
Appearance
Sterile Filtered White lyophilized (freeze-dried) powder.
Purity
> 98 % by SDS-PAGE and HPLC analyses.
Biological Activity
The ED50 as determined by a cell proliferation assay using human A375 cell line is less than 5 μg/mL, corresponding to a specific activity of > 200 IU/mg. Fully biologically active when compared to standard.
Endotoxin
< 0.1 EU per 1μg of the protein by the LAL method.
Formulation
Lyophilized from a 0.2 µm filtered concentrated solution in PBS, pH 7.4, with 5 % Trehalose.
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.