KRAS(G12C) Coupled Nucleotide Exchange Assay Kit

Catalog #
78565
$1,355 *
Size: 384 reactions
Qty
*US Pricing only. For international pricing, please contact your local distributor.
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Description

The KRAS(G12C) Coupled Nucleotide Exchange Assay Kit is designed for screening and profiling of KRAS(G12C) antagonists/inhibitors by monitoring the binding of an effector protein such as the Ras binding domain of Raf1, (RBD-cRaf) to KRAS(G12C). With this kit, a few simple steps on a microtiter plate are required for nucleotide exchange detection. First, a sample containing GDP-loaded KRAS(G12C) is incubated with SOS1 and GTP for the nucleotide exchange. Next, RBD-cRAF is added and incubated for the effector-RAS binding. Then, acceptor and donor beads are added and incubated for detection followed by reading the Alpha-counts.

SOS1 (son of sevenless) is a guanine nucleotide exchange factor that facilitates the exchange of GDP for GTP. GDP-loaded KRAS(G12C) is in an inactive state, and does not interact with the Ras-binding domain (RBD) of cRAF.  SOS1 assists in the release of GDP from KRAS(G12C) so that GTP can occupy the nucleotide binding pocket. This results in a conformational change in KRAS(G12C) that permits its binding to RBD-cRAF. The KRAS(G12C) Coupled Nucleotide Exchange Assay Kit utilizes GST-tagged RBD-cRAF and His-tagged KRAS (G12C) to assay binding of KRAS(G12C) to RBD-cRAF in the Alpha assay. Glutathione acceptor and Ni chelate donor beads are brought into proximal range by the binding of KRAS(G12C) and RBD-cRAF, enabling the energy transfer from the donor to acceptor beads after laser excitation. 

Figure 1: Illustration of the assay principle.

Product Info
Storage and Usage
Citations
Assay Kit Format
AlphaLISA®
Supplied As
The KRAS(G12C) Coupled Nucleotide Exchange Assay Kit comes in a convenient 384-well format, with enough purified recombinant GDP-loaded KRAS(G12C) Isoform A, GTP, exchange factor SOS1, an effector protein RBD-cRAF, assay buffer and additives for 400 reactions.
Materials Required But Not Supplied
Name Ordering Information
AlphaLISA® Glutathione acceptor beads, 5 mg/ml PerkinElmer #AL109C
AlphaScreen® Nickel Chelate donor beads, 5 mg/ml PerkinElmer #AS101D
Optiplate -384 PerkinElmer #6007290
AlphaScreen® microplate reader  
Adjustable micropipettor and sterile tips  
Format
Catalog # Name Amount Storage
100640 GDP-loaded KRAS(G12C), Isoform A, His-tag* 10 µg -80°C
101573 SOS1, FLAG-Tag* 50 µg -80°C
100519 RBD-cRAF, GST-tag* 5 µg -80°C
79861-2 GTP (10 mM) 0.5 ml -20°C
  RBD-RAS Binding Buffer (Incomplete) 2 x 3 ml -20°C
  DTT (0.5 M) 2 x 200 µl -20°C
79311 3x Immuno Buffer 1 4 ml -20°C

*The concentration of the protein is lot-specific and will be indicated on the tube.

UniProt #
P01116
Background

It is well established that RAS mutations are responsible for more than 30% of human cancers. KRAS(G12C) is one of the KRAS mutations that is found frequently in lung and colon cancers. The G12C mutation favors the activated (GTP-bound) state of KRAS, amplifying signaling pathways that lead to oncogenesis. Recent studies have led to the discovery of a small molecule called AMG510 (Amgen) that locks KRAS conformation in the GDP-bound (inactive) state, thereby blocking KRAS(G12C)-mediated signaling pathway.  Compounds that affect the nucleotide exchange (GDP to GTP) reaction could lead to a novel approach leading to the inhibition of tumor cell growth in KRAS(G12C) driven tumors.