Ribonucleotide reductase (RNR, class Ia)
Clinical / pharmacological. Target of hydroxyurea; allosterically controlled by dNTPs
What it does, reaction by reaction
Deoxyribonucleotide Formation (Ribonucleotide Reductase pathway and thymidylate synthesis) Nucleotide Metabolism · Cytosol
Nucleoside diphosphates → deoxyribonucleoside diphosphates
Converts ADP GDP CDP UDP into dADP dGDP dCDP dUDP
› Notes
Class Ia RNR catalyzes ADP, GDP, CDP, or UDP + reducing equivalents → dADP, dGDP, dCDP, or dUDP + oxidized electron-transfer proteins. The human enzyme is an alpha2beta2 complex: the RRM2/RRM2B small subunit uses a diiron center to generate a stable tyrosyl radical, and the RRM1 large subunit contains catalytic cysteines that reduce the 2′-hydroxyl group. Reducing equivalents are transferred from NADPH through thioredoxin reductase and reduced thioredoxin (or through NADPH, glutathione reductase, glutathione, and glutaredoxin); the chemical reduction of each NDP requires one NADPH-derived pair of electrons. This is the rate-limiting and committed step for de novo deoxyribonucleotide production.
Showing all 1 reactions.
What accelerates and inhibits it
Regulation is pathway-specific, so each context is listed separately
No regulation recorded for this enzyme in the source documents.
Recent literature
Europe PMC · fetched just now · sorted by publication date
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1
Stress-specific 14-3-3-client modules in digestive cancers: an evidence-graded review of adaptive survival and therapy resistance.
Li R, Zhao Z, Wang X. · 2026-07-27
open access unreviewed -
2
Mechanistic studies on HNRNPA2B1 suggest binding but not selective recognition of m<sup>6</sup>A.
Park R, Demny M, Miller LG, Pedraza C, Xenophontos X, Hunt RK, Orr AA, Perez LM, Montalbano M, Contreras LM, … · 2026-03-02
cited 1× open access unreviewed -
3
DND1–NANOS3 shapes the PGC transcriptome via a heptanucleotide sequence in mRNA 3′-UTRs
Suzawa M, Qiu C, Polash A, Yamaji M, Jacob A, Horikawa W, Farroha E, Barua M, Feng X, Liu C, Williams J, Rand… · 2026-10-05
unreviewed -
4
Capturing Hu Antigen R Domain Closure Through Supervised Molecular Dynamics Simulations.
Cavastracci Strascia C, Dodaro A, Novello G, Menin S, Sturlese M, Salmaso V, Moro S. · 2026-10-01
open access unreviewed -
5
Engineering a protein homodimer from a heterodimer: A chimeric DBHS protein.
Marshall AC, Mohnen I, Gomez AV, Fox AH, Knott GJ, Bond CS. · 2026-10-01
open access unreviewed -
6
TDP-43 drives ferroptosis evasion by modulating PCBP1/PCBP2 axis to promote lung adenocarcinoma growth.
Liu B, Chen X, Chen J, Feng J, Wang J, Jin X, Cao J, Zhao B, Yin H, Wang J, Yang Y, Zheng P, Ma S, Liao W, Zh… · 2026-08-10
open access unreviewed -
7
Crossroad of motor neuron disease and dementia: Insights from TDP-43 RNA-binding deficiency.
Magarotto M, Chen HJ. · 2026-01-27
open access unreviewed -
8
The RNA-Binding Protein ELAVL4/HuD Promotes Stress-Associated Tumor Survival in Neuroendocrine Cancers.
Bishayee K, Kaviyarasan V, Yoo SY, Lee SH, Park YS. · 2026-09-03
open access unreviewed -
9
Ribonucleotide Reductase Inhibition Triggers Ferroptosis in Genetically Defined Subsets of Non-Small Cell Lung Cancer.
Sen U, Natour D, Chakraborty S, Gobbini E, Fan CW, Koelbel C, Elliott A, Vanderwalde AM, Borghaei H, Halmos B… · 2026-09-01
open access unreviewed -
10
ERCC6 at the Transcription-Replication Interface: Integration of Transcription-Coupled Repair with Replication Stress Responses.
Zambrano E, Morales F, Bernal YA, Marcelain K. · 2026-08-19
open access unreviewed
External claims. These come from an index outside this database and are not checked against it. Treat them as leads.