HUMAN G PROTEIN ALPHA SUBUNIT Gxi1 WITH AT LEAST ONE MUTATED AMINO ACID RESIDUE

Simple SummaryContent extracted from patent full text and abstract with AI.

This patent describes specific engineered variants (mutants) of the human G protein alpha subunit (Gαi1), a key component in cellular signaling pathways. By systematically replacing certain amino acids with alanine or glycine, the invention maps out which residues are crucial for stabilizing different conformational states of the Gαi1 protein—such as when it binds to nucleotides, interacts with receptors, or transitions between active and inactive forms. These mutant proteins can show altered stability or binding characteristics, which is valuable for both research and potential therapeutic applications.

Use CasesContent extracted from patent full text and abstract with AI.

• Facilitating structural studies of G protein-coupled receptor (GPCR) and G protein complexes by providing more stable complexes for crystallography or cryo-EM.
• Development of biosensors to monitor G protein activation with improved or altered response characteristics.
• Screening of drugs or ligands that target GPCR signaling pathways using the stabilized Gαi1 mutants.
• Studying mechanisms of signal transduction at the molecular level, helping to better understand allosteric activation in G proteins.
• Potentially engineering therapeutic proteins or tools to modulate GPCR signaling in diseases where this pathway is dysregulated.

BenefitsContent extracted from patent full text and abstract with AI.

• Provides a comprehensive single-residue functional map for Gαi1, enhancing understanding of protein activation and signaling.
• Enables the stabilization of specific G protein conformations, improving experimental reproducibility and reliability in protein studies.
• Mutant proteins can be tailored for specific applications, such as higher thermostability or altered binding, optimizing them for research or industrial use.
• May accelerate structure-based drug discovery targeting GPCR/G protein interactions by enabling high-quality structural data.
• Facilitates comparative studies across G protein family members, due to the use of standardized residue numbering and broad sequence alignment.

Technical Classifications (CPCs)

Inventors & Applicants

Patent Abstract

In this application, a comprehensive maps at single amino acid resolution of the residues stabilising the Gαi1subunit in nucleotide-and receptor-bound states is given. These maps were generated by measuring the effects of alanine mutations on the stability of Gαi1and of the rhodopsin-Gαi1complex. Using these data, stabilization clusters in the GTPase and helical domains have been identified responsible for structural integrity and the conformational changes associated with activation. In activation cluster I, helices α1 and α5 pack against strands β1-3 to stabilize the nucleotide-bound states. In the receptor-bound state, these interactions are replaced by interactions between α5 and strands β4-6.The key residues in this cluster are Y320, crucial for the stabilisation of the receptor-bound state, and F336, which stabilises nucleotide-bound states. Destabilisation of helix α1, caused by rearrangement of this activation cluster, leads to the weakening of the inter-domain interface and release of GDP. The present application discloses in detail mutant ligands of the human G protein alpha-subunit –Gαi1-, wherein at least one amino acid residue has been replaced with alanine if the at least one amino acid residue is a non-alanine residue,or at least one amino acid residue has been replace with glycine if the at least one amino acid residue is alanine and wherein the at least one amino acid residue is comprised in a first group containing of the amino acid residues with position R32A, K54A, I55A, I56A, H57A, R176A, E245A, Y296A, T327A, N331A, V332A and D350A or is comprised in a second group containing G42A, A59G, T177A, D200A, A226G, E297A, A300G and F334A or is comprised in a third group containing V50A, A59G, R178A 30 and K180A.