Skip to content
MS
unreviewed

Ribonucleotide reductase (RNR)

1 reactions · 1 pathways

Clinical / pharmacological. Target of hydroxyurea; allosterically controlled by dNTPs

What it does, reaction by reaction

1 reactions

Pyrimidine De Novo Synthesis (through to UMP, then CTP/dTMP) Nucleotide Metabolism · Cytosol (one mitochondrial step)

step 10 Irreversible/directional

UDP → dUDP (route to dUMP)

Converts UDP into dUDP

› Notes

Ribonucleotide reductase (RNR) catalyzes UDP + reducing equivalents → dUDP + oxidized electron-transfer proteins. In humans the reducing equivalents are supplied principally by NADPH through thioredoxin reductase and thioredoxin (or through glutaredoxin/glutathione); RNR is covered mechanistically in the deoxyribonucleotide section.

Showing all 1 reactions.

What accelerates and inhibits it

Regulation is pathway-specific, so each context is listed separately

1 entries

Deoxyribonucleotide Formation (Ribonucleotide Reductase pathway and thymidylate synthesis)

Accelerated by

ATP at the activity site; substrate specificity is directed by ATP/dATP, dTTP, and dGTP at the specificity site

Inhibited by

dATP at the activity site (global feedback inhibition); hydroxyurea quenches the radical; iron limitation impairs radical-center assembly

Hormonal control

Transcription and activity rise in late G1/S through E2F and proliferative growth-factor signaling; p53-induced RRM2B supports DNA repair under stress.

Recent literature

Europe PMC · fetched just now · sorted by publication date

  1. 1
  2. 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. 3
    Targeting IMPDH to inhibit SAMHD1 in <i>KMT2A</i>-rearranged leukaemia.

    Klootsema Y, Tsesmetzis N, Sharma S, Hofmann S, Thier J, Dirks C, Hormann FM, Yagüe-Capilla M, Bohlin A, Beng… · 2025-12-15

    open access unreviewed
  4. 4
    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
  5. 5
    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
  6. 6
    The next generation of orthopoxvirus antivirals: preparing for future threats.

    Jagtap AD, Yang Z, Wang Z. · 2026-10-02

    unreviewed
  7. 7
    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
  8. 8
    Resolution and Quantitation of Ribonucleosides and Deoxyribonucleosides in Digested Genomic DNA by UHPLC-MS/MS.

    Deppas JJ, Jones R, Parise RA, Pandya P, Bakkenist CJ, Beumer JH. · 2026-10-01

    open access unreviewed
  9. 9
    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
  10. 10
    The role of metals in cancer and the use of metal chelators as a potential treatment strategy.

    Leal MFC, Rocha DA, Cardoso IL. · 2026-07-20

    open access unreviewed

External claims. These come from an index outside this database and are not checked against it. Treat them as leads.