1. Academic Validation
  2. Cytosolic Iron-Sulfur Assembly Is Evolutionarily Tuned by a Cancer-Amplified Ubiquitin Ligase

Cytosolic Iron-Sulfur Assembly Is Evolutionarily Tuned by a Cancer-Amplified Ubiquitin Ligase

  • Mol Cell. 2018 Jan 4;69(1):113-125.e6. doi: 10.1016/j.molcel.2017.11.010.
Jenny L Weon 1 Seung Wook Yang 1 Patrick Ryan Potts 2
Affiliations

Affiliations

  • 1 Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105-3678, USA.
  • 2 Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105-3678, USA. Electronic address: [email protected].
Abstract

The cytosolic iron-sulfur (Fe-S) cluster assembly (CIA) pathway functions to incorporate inorganic Fe-S cofactors into a variety of proteins, including several DNA repair enzymes. However, the mechanisms regulating the CIA pathway are unknown. We describe here that the MAGE-F1-NSE1 E3 ubiquitin ligase regulates the CIA pathway through ubiquitination and degradation of the CIA-targeting protein MMS19. Overexpression or knockout of MAGE-F1 altered Fe-S incorporation into MMS19-dependent DNA repair enzymes, DNA repair capacity, sensitivity to DNA-damaging agents, and iron homeostasis. Intriguingly, MAGE-F1 has undergone adaptive pseudogenization in select mammalian lineages. In contrast, MAGE-F1 is highly amplified in multiple human Cancer types and amplified tumors have increased mutational burden. Thus, flux through the CIA pathway can be regulated by degradation of the substrate-specifying MMS19 protein and its downregulation is a common feature in Cancer and is evolutionarily controlled.

Keywords

DNA repair; MAGE; MMS19; NSE1; cancer; iron sulfur; ubiquitination.

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