Source:http://linkedlifedata.com/resource/umls/id/C1259395
NCI: Encoded by human RRM1 Gene, Ribonucleoside-Diphosphate Reductase M1 Chain is 1 of 2 ribonucleoside-diphosphate reductase subunits, a heterodimeric cytoplasmic enzyme essential in dividing cells that reduces ribonucleotides to deoxyribonucleotide precursors for DNA synthesis in S phase. Complex allosteric control, mediated by deoxynucleoside triphosphates, and by ATP bound to the M1 subunit prevents DNA replication and cell proliferation. A substrate specificity site and a catalytic activity site regulate enzyme activity. A substrate-binding catalytic site on M1 is only formed in the presence of M2. Enzyme activity closely correlates with the cellular rate of growth and appears to vary with the cell cycle. RRM1 functions as a metastasis suppressor gene through induction of PTEN expression and PTEN-regulated pathways. (from Swiss-Prot, OMIM, LocusLink and NCI)