RRM1 also known as R1 is a key component of the ribonucleotide reductase complex, catalyzes ribonucleotide conversion to deoxyribonucleotides for DNA synthesis. RRM1 plays a crucial role in the synthesis of deoxyribonucleotide triphosphates (dNTPs), the building blocks necessary for DNA replication and repair. The RRM1 subunit is notable for allosteric regulatory sites, which allow responses to cellular signals and modulate enzyme activity, thereby ensuring appropriate dNTP levels during the cell cycle. This regulation supports the fidelity of DNA synthesis and repair processes, vital for maintaining genomic stability. Additionally, ribonucleotide reductase participates in nucleotide excision repair, with both RRM1 and RRM2 subunits being induced in response to UV light, highlighting their role in cellular responses to DNA damage.