RAS & KRAS Proteins

RAS proteins are crucial in cancer research due to their role in cellular signal transduction. As a family of small GTPases, RAS proteins—including HRAS, KRAS, and NRAS—are among the most common oncogenes in human cancers. KRAS mutations, notably G12C, G12D, G12V, G13D, and Q61H, are highly prevalent in tumors, making them vital targets for oncology drug discovery, including the development of small-molecule inhibitors and molecular glues.

Amid Biosciences supports this critical research area by offering an extensive range of high-purity recombinant biotinylated and non-biotinylated RAS proteins, including wild-type and mutant KRAS, HRAS, and NRAS GTPases. Our proteins are engineered as essential tools for binding assays, structural biology, and high-throughput screening (HTS). Additionally, we provide custom services for loading RAS proteins with specific nucleotides (GTP/GDP) or their analogs to fit your precise experimental needs.

To complement your RAS signal transduction pathway research, we also provide key regulatory biomolecules, effector domains, and upstream / downstream targets, including:

Select RAS & KRAS Proteins by Category

Find assay-ready KRAS mutant proteins, nucleotide-loaded KRAS formats, biotinylated KRAS reagents, RAS-family GTPases, pathway proteins, and custom RAS protein services.

KRAS G12D Proteins

Recombinant KRAS G12D proteins for oncology research, binding assays, nucleotide exchange workflows, and drug discovery.

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KRAS G12C Proteins

KRAS G12C proteins for covalent inhibitor research, biochemical assays, and targeted oncology workflows.

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KRAS G12V Proteins

KRAS G12V proteins for RAS signaling studies, effector binding assays, and inhibitor screening.

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Nucleotide-Loaded KRAS Proteins

GDP-loaded and GppNHp-loaded KRAS proteins for defined nucleotide-state assay workflows.

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Biotinylated KRAS Proteins

Site-specifically biotinylated KRAS proteins for SPR, BLI, AlphaScreen, ELISA, and pull-down assays.

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KRAS Effector & Regulatory Proteins

SOS1, RAF1-RBD, PI3Kα-RBD, RALGDS-RBD, NF1-GRD, SHP2, and related pathway proteins.

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RAS-Family GTPases

KRAS, NRAS, HRAS, RALA, RALB, RHEB, and related small GTPase proteins.

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KRAS Proteins Used in Published Research

KRAS proteins and RAS pathway reagents used in peer-reviewed assay development and drug discovery studies.

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Custom RAS Protein Services

Custom KRAS mutations, site-specific biotinylation, nucleotide loading, assay-ready formats, and bulk production.

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RAS & KRAS Protein Selection Guide

Use this guide to select KRAS mutant proteins, nucleotide-loaded KRAS formats, biotinylated assay reagents, RAS-family GTPases, and KRAS pathway companion proteins for your workflow.

Protein Group Available Formats Common Applications Related Collection
KRAS G12D Biotinylated, AviTag™, GDP-loaded, GppNHp-loaded Nucleotide exchange assays, inhibitor screening, binding assays, oncology research KRAS G12D Proteins
KRAS G12C Biotinylated, AviTag™, GDP-loaded, GppNHp-loaded, Y96D-related formats Covalent inhibitor workflows, KRAS drug discovery, nucleotide-state assays KRAS G12C Proteins
KRAS G12V Biotinylated, AviTag™, C-terminal biotinylated, no His-tag formats Effector binding, RAS signaling studies, inhibitor screening KRAS G12V Proteins
Nucleotide-loaded KRAS GDP-loaded and GppNHp-loaded KRAS formats Defined nucleotide-state assays, exchange workflows, effector binding, inhibitor profiling Nucleotide-Loaded KRAS Proteins
Biotinylated KRAS N-terminal and C-terminal site-specific biotinylation formats SPR, BLI, AlphaScreen, ELISA, pull-down assays, streptavidin capture workflows Biotinylated KRAS Proteins
KRAS effector and regulatory proteins SOS1, RAF1-RBD, PI3Kα-RBD, RALGDS-RBD, NF1-GRD, SHP2, and related proteins Pathway interaction assays, nucleotide exchange workflows, effector binding studies KRAS Effector & Regulatory Proteins
RAS-family GTPases KRAS, NRAS, HRAS, RALA, RALB, RHEB, and related small GTPases Small GTPase pathway research, biochemical assays, binding studies, drug discovery RAS-Family GTPases

GDP-Loaded and GppNHp-Loaded KRAS Proteins

Defined nucleotide-loaded KRAS proteins help reduce preparation steps and improve consistency in nucleotide-state-dependent assay workflows.

GDP-Loaded KRAS

GDP-loaded KRAS proteins are useful for nucleotide exchange assays, SOS1-mediated exchange workflows, GDP-state studies, and experiments that begin from a defined inactive-state conformation.

GppNHp-Loaded KRAS

GppNHp-loaded KRAS proteins support active-state KRAS assays, effector binding studies, inhibitor profiling, and workflows requiring a stable GTP-like conformation.

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KRAS Effector and Regulatory Proteins

Pair KRAS mutant proteins with pathway companion proteins for effector binding assays, nucleotide exchange workflows, pathway interaction studies, and drug discovery assay development.

SOS1 RAF1-RBD PI3Kα-RBD RALGDS-RBD NF1-GRD SHP2 MEK1 / MEK2 RALA / RALB
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Published Research Using Amid RAS-Pathway Proteins

Amid Biosciences' RAS-family proteins have been used in published research from leading academic and industry laboratories, including the lab of Prof. Kevan Shokat (UCSF/HHMI) — a pioneer in KRAS drug discovery whose work on the G12C switch-II cryptic pocket opened the modern era of direct RAS inhibition.

Our biotinylated KRAS mutant proteins and SOS1 have been used in high-throughput nucleotide exchange assays to characterize next-generation KRAS inhibitors and degraders.

  1. Morstein J, Bowcut V, Fernando M, et al. Targeting Ras-, Rho-, and Rab-family GTPases via a conserved cryptic pocket. Cell. 2024;187(22):6379–6392.e17. doi:10.1016/j.cell.2024.08.017
  2. Kidane M, Hoffman RM, Wolfe-Demarco JK, et al. Suite of Biochemical and Cell-Based Assays for the Characterization of Kirsten Rat Sarcoma (KRAS) Inhibitors and Degraders. ACS Pharmacol Transl Sci. 2024;7(12):3921–3934. doi:10.1021/acsptsci.4c00450
  3. Kage M, Hayashi R, Matsuo A, et al. Structure-activity relationships of middle-size cyclic peptides, KRAS inhibitors derived from an mRNA display. Bioorg Med Chem. 2024;110:117830. doi:10.1016/j.bmc.2024.117830

KRAS inhibitor and degrader assay development

Biotinylated KRAS mutant proteins and SOS1 were used in biochemical assay workflows for KRAS inhibitor and degrader characterization.

Pan-GTPase druggability research

RAS-family and related small GTPase reagents support research into conserved GTPase binding pockets and pathway-targeted drug discovery.

View Cited RAS-Pathway Proteins

Need a Custom RAS Protein?

Request custom KRAS mutations, tag placement, site-specific biotinylation, GDP or GppNHp nucleotide loading, assay-ready formats, custom QC, and bulk production.

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FAQ

Which KRAS mutation should I choose?

Choose the KRAS mutation that matches your biological model, assay target, or inhibitor program. KRAS G12D, G12C, and G12V are commonly used in oncology drug discovery and RAS pathway research.

When should I use GDP-loaded versus GppNHp-loaded KRAS?

GDP-loaded KRAS is useful when starting from a defined inactive-state conformation or running nucleotide exchange assays. GppNHp-loaded KRAS is useful for active-state workflows, effector binding studies, and GTP-like assay formats.

When should I choose biotinylated KRAS?

Biotinylated KRAS is useful for streptavidin-based capture workflows, including SPR, BLI, AlphaScreen, ELISA, pull-down assays, and related surface-based biochemical assays.

Do you offer C-terminally biotinylated KRAS?

Yes. Amid Biosciences offers site-specifically biotinylated KRAS formats, including C-terminally biotinylated constructs for workflows where N-terminal tag placement may not be preferred.

Can Amid Biosciences make custom KRAS mutants?

Yes. Custom RAS protein services are available for KRAS mutations, tag placement, nucleotide loading, assay-ready formats, custom QC, and bulk production.

Are these products for research use only?

Yes. These products are intended for research use only and are not intended for diagnostic or therapeutic use.

Research Use Only. These products are for research use only and are not intended for diagnostic or therapeutic use.

Table 1. KRAS and KRAS-related proteins by mutation type