Cytosolic iron-sulfur protein assembly system identifies clients by a C-terminal tripeptide

Marquez, M. D.; Greth, C.; Buzuk, A.; Liu, Y.; Blinn, C. M.; Beller, S.; Leiskau, L.; Hushka, A.; Wu, K.; Nur, K.; Netz, D. J. A.; Perlstein, D. L.; Pierik, A. J.

doi:10.1101/2023.05.19.541488

bioRxiv · 10.1101/2023.05.19.541488

Cytosolic iron-sulfur protein assembly system identifies clients by a C-terminal tripeptide

Marquez, M. D.·Greth, C.·Buzuk, A.·Liu, Y.·Blinn, C. M.·Beller, S.·Leiskau, L.·Hushka, A.·Wu, K.·Nur, K.·Netz, D. J. A.·Perlstein, D. L.·Pierik, A. J.

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Abstract

The eukaryotic cytosolic Fe-S protein assembly (CIA) machinery inserts iron-sulfur (Fe-S) clusters into cytosolic and nuclear proteins. In the final maturation step, the Fe-S cluster is transferred to the apo-proteins by the CIA-targeting complex (CTC). However, the molecular recognition determinants of client proteins are unknown. We show that a conserved [LIM]-[DES]-[WF]-COO- tripeptide present at the C-terminus of clients is necessary and sufficient for binding to the CTC in vitro and directing Fe-S cluster delivery in vivo. Remarkably, fusion of this TCR (target complex recognition) signal enables engineering of cluster maturation on a non-native protein via recruitment of the CIA machinery. Our study significantly advances our understanding of Fe-S protein maturation and paves the way for bioengineering applications. One-Sentence SummaryA C-terminal tripeptide guides eukaryotic iron-sulfur cluster insertion into cytosolic and nuclear proteins.

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Marquez, M. D., Greth, C., Buzuk, A., Liu, Y., Blinn, C. M., Beller, S., Leiskau, L., Hushka, A., Wu, K., Nur, K., Netz, D. J. A., Perlstein, D. L., Pierik, A. J.. 2023-05-20. Cytosolic iron-sulfur protein assembly system identifies clients by a C-terminal tripeptide. https://doi.org/10.1101/2023.05.19.541488

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