The deca-GX3 proteins Yae1-Lto1 function as adaptors recruiting the ABC protein Rli1 for iron-sulfur cluster insertion
- Philipps-Universität, Germany
- Friedrich Miescher Institute for Biomedical Research, Switzerland
- European Molecular Biology Laboratory, Germany
- Philipps-Universität Marburg, Germany
Abstract
Cytosolic and nuclear iron-sulfur (Fe-S) proteins are involved in many essential pathways including translation and DNA maintenance. Their maturation requires the CIA (cytosolic Fe S protein assembly) machinery. To identify new CIA proteins we employed systematic protein interaction approaches and discovered the essential proteins Yae1 and Lto1 as binding partners of the CIA targeting complex. Depletion of Yae1 or Lto1 results in defective Fe-S maturation of the ribosome-associated ABC protein Rli1, but surprisingly no other tested targets. Yae1 and Lto1 facilitate Fe-S cluster assembly on Rli1 in a chain of binding events. Lto1 uses its conserved C-terminal tryptophan for binding the CIA targeting complex, the deca-GX3 motifs in both Yae1 and Lto1 facilitate their complex formation, and Yae1 recruits Rli1. Human YAE1D1 and the cancer-related ORAOV1 can replace their yeast counterparts demonstrating evolutionary conservation. Collectively, the Yae1-Lto1 complex functions as a target-specific adaptor that recruits apo-Rli1 to the generic CIA machinery.
Article and author information
Author details
Reviewing Editor
- Dennis Dean, Virginia Polytechnic Institute and State University, United States
Version history
- Received: April 21, 2015
- Accepted: July 15, 2015
- Accepted Manuscript published: July 16, 2015 (version 1)
- Version of Record published: August 4, 2015 (version 2)
Copyright
© 2015, Désirée Paul et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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The deca-GX3 proteins Yae1-Lto1 function as adaptors recruiting the ABC protein Rli1 for iron-sulfur cluster insertion
eLife 4:e08231.
https://doi.org/10.7554/eLife.08231
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