| Source: |
Escherichia coli |
| Molecular Weight: |
Approximately 16.5 kDa, a single non-glycosylated polypeptide chain containing 156 amino acids. |
| AA Sequence: |
MEPAAGSSME PSADWLATAA ARGRVEEVRA LLEAGALPNA PNSYGRRPIQ VMMMGSARVA ELLLLHGAEP NCADPATLTR PVHDAAREGF LDTLVVLHRA GARLDVRDAW GRLPVDLAEE LGHRDVARYL RAAAGGTRGS NHARIDAAEG PSDIPD |
| Purity: |
> 96% by SDS-PAGE and HPLC analyses. |
| Physical Appearance: |
Sterile filtered white lyophilized (freeze-dried) powder. |
| Formulation: |
Lyophilized from a 0.2 µm filtered concentrated solution in PBS, pH7.4. |
| Endotoxin: |
Less than 1 EU/µg of rHuP16-INK4a as determined by LAL method. |
| 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°C. Further dilutions should be made in appropriate buffered solutions. |
| Stability & Storage: |
Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
12 months from date of receipt, -20 to -70°C as supplied.
1 month, 2 to 8°C under sterile conditions after reconstitution.
3 months, -20 to -70°C under sterile conditions after reconstitution. |
| Synonyms: |
CDK4I, MTS-1, p16INK4A |
| Background: |
Cyclin-dependent kinase inhibitors (CDKIs) are proteins that bind to and inhibit CDK activity. They fall into two main classes. The p16 family (p15, p16, p18, and p19) binds specifically to CDK4 and CDK6, blocking their function. The p21 family (p21, p27, p28, and p57) can bind a wide range of CDK-cyclin complexes, inhibiting their activity. CDKIs have the capacity to suppress cellular growth, and there is compelling evidence suggesting that some CDKIs function as tumor suppressors.
Among the p16 family, p16-INK4A, encoded by the CDKN2A gene in humans, is notable. It exists in three isoforms, widely expressed but absent in the brain and skeletal muscle, except for isoform 3, which is pancreas-specific. Mutations in p16-INK4A are linked to disorders such as Li-Fraumeni syndrome (LFS) and melanoma-astrocytoma syndrome (MASTS). |
