Purine nucleotide-binding proteins

Purine nucleotide-binding proteins represent a vast and diverse superfamily of proteins characterized by their ability to bind purine nucleotides, most notably adenosine triphosphate (ATP) and guanosine triphosphate (GTP) (UniProt, 2024). This group encompasses several major functional classes, including protein kinases, small GTPases (like Ras), heterotrimeric G-proteins, motor proteins (like myosin and kinesin), and various metabolic enzymes (PubMed, 2021). These proteins play fundamental roles in cellular life, serving as molecular switches in signal transduction, providing energy for mechanical work, and acting as substrates for phosphorylation (NIH, 2023). Due to their central role in regulating cell growth, survival, and metabolism, many members of this class are high-priority therapeutic targets in diseases such as cancer and inflammation (StatPearls, 2024). However, the 'unspecified' designation typically indicates a lack of specific protein identification in experimental data, reflecting the challenge of achieving selectivity among proteins that share highly conserved nucleotide-binding motifs, such as the Walker A motif or P-loop (ChEMBL, 2024). Drug development for this class often focuses on achieving high specificity for a single protein member to avoid the toxicity associated with pan-inhibition of the purine-binding sub-proteome (PubMed, 2022).

Other names

Purine nucleotide-binding proteins – unspecifiedPurine-binding proteinsNucleotide-binding proteinsATP-binding proteinsGTP-binding proteinsPurine ribonucleotide-binding proteins

Drugs targeting these proteins typically act through competitive inhibition of the purine nucleotide-binding pocket (e.g., the ATP-binding site in kinases or the GTP-binding site in GTPases), allosteric modulation to prevent nucleotide exchange, or covalent modification of conserved residues within the binding domain (PubMed, 2023).