Human KRAS / K-Ras (G12D & Q61H) Protein (His Tag)

K-Ras belongs to the small GTPase superfamily, Ras family. Like other members of the Ras family, K-Ras is a GTPase and is an early player in many signal transduction pathways. It is usually tethered to cell membranes because of the presence of an isoprenyl group on its C-terminus. K-Ras functions as a molecular on/off switch. Once it is turned on it recruits and activates proteins necessary for the propagation of growth factor and other receptors' signal, such as c-Raf and PI 3-kinase. It binds to GTP in the active state and possesses an intrinsic enzymatic activity that cleaves the terminal phosphate of the nucleotide converting it to GDP. Upon conversion of GTP to GDP, K-Ras is turned off. The rate of conversion is usually slow but can be sped up dramatically by an accessory protein of the GTPase activating protein class, for example, RasGAP. In turn, K-Ras can bind to proteins of the Guanine Nucleotide Exchange Factor class, for example, SOS1, which forces the release of bound nucleotide. Subsequently, K-Ras binds GTP present in the cytosol and the GEF is released from ras-GTP. Besides essential function in normal tissue signaling, the mutation of a K-Ras gene is an essential step in the development of many cancers. Several germline K-Ras mutations are associated with Noonan syndrome and Cardio-Facio-Cutaneous syndrome. Somatic K-Ras mutations are found at high rates in Leukemias, colon cancer, pancreatic cancer, and lung cancer.

C-K-RAS Protein, Human; CFC2 Protein, Human; K-RAS Protein, Human; K-RAS2A Protein, Human; K-RAS2B Protein, Human; K-RAS4A Protein, Human; K-RAS4B Protein, Human; KI-RAS Protein, Human; KRAS1 Protein, Human; KRAS2 Protein, Human; NS Protein, Human; NS3 Protein, Human; RALD Protein, Human; RASK2 Protein, Human

At Leading Biology, the biological activity of a recombinant protein is routinely measured using a bioassay, e.g. chemotaxis or cell proliferation assay, enzyme assay, or a functional ELISA. When a recombinant protein is an enzyme, specific activity is derived from an enzymatic assay. Each enzyme is tested for potency by cleavage of a substrate. We are in the process of updating the biological activity data. If you have any questions regarding this update, please feel free to contact our technical support team.

Lyophilized from sterile PBS, pH 7.4. Please contact us for any concerns or special requirements. Normally 5 % - 8 % trehalose, mannitol and 0.01% Tween 80 are added as protectants before lyophilization. Please refer to the specific buffer information in the hard copy of CoA.

The recombinant human KRAS consists of 202 amino acids and has a calculated molecular mass of 23.3 kDa. It migrates as an approximately 25.2 and 28.9 KDa band in SDS-PAGE under reducing conditions.

In general, recombinant proteins are provided as lyophilized powder which are shipped at ambient temperature. Bulk packages of recombinant proteins are provided as frozen liquid. They are shipped out with blue ice unless customers require otherwise. Stable for 1 year at -20°C or below from date of shipment. For maximum recovery of product, centrifuge the original vial after thawing and opening the cap. For long-term storage, aliquot and store at -20°C or below. Avoid repeated freeze-thaw cycles.

A DNA sequence encoding the human KRAS (P01116-2) (Thr2-Cys185, with natural variant Gly 12 Asp and Gln 61 His) was expressed with a polyhistide tag at the N-terminus.