The KRAS gene plays important roles in cell division, cell differentiation, and apoptosis. We offer an assortment of KRAS recombinant protein, kits, and services to advance your research and drug discovery needs.

• Kras wild-type and mutants (G12C, G12D, G12R, G12V) (apo)
• Kras wild-type and mutants (G12C, G12D, G12R, G12V) + GDP loaded
• Kras wild-type and mutants (G12C, G12D, G12R, G12V) + GppNHp loaded (for activity binding assay)
• Kras wild-type and mutants (G12C, G12D, G12R, G12V) TR-FRET based Nucleotide exchange assay kits
• Kras wild-type and mutants (G12C, G12D, G12R, G12V) TR-FRET based Kras -cRAF binding assay
• Kras assay services (Compound screening and profiling)
• Human recombinant SOS1 and cRAF

Our Nucleotide exchange assay for our kits/service is a TR-FRET based assay. The assay kit is designed to detect the GTP binding status of Kras in the presence of SOS1, a known Kras Guanine exchange factor. The Kras in our assay has a GST tag, that can bind to a Terbium-labeled anti-GST antibody (HTRF donor). If the Kras binds to a fluorescence-labeled GTP (HTRF acceptor), the donor and the acceptor will be brought in close proximity. Excitation of Terbium (340 nm) generates fluorescence resonance energy transfer (FRET) to fluorescence-labeled GTP acceptor, which emits specific fluorescence at 665 nm (figure below). Thus, GTP binding to the Kras can be quantitively measured by calculation of fluorescent ratio of 665 nm/620 nm.

The Kras-cRAF binding assay is a TR-FRET based assay. In this assay, Kras is loaded with GppNHp, representing the activated Kras. The assay kit is designed to detect binding between Kras and cRAF. The Kras in this assay kit has a GST tag, that can bind to a Terbium-labeled anti-GST antibody (HTRF donor), and cRAF in this assay kit has a His tag, that can bind to a fluorescence-labeled anti-His antibody (HTRF acceptor). The binding of Kras with cRAF results in fluorescence resonance energy transfer (FRET) from the HTRF donor to the HTRF acceptor when the donor is activated allowing cRAF binding to be measured.