Functional and structural characterization of the mitochondrial Iron-Sulfur Cluster Complex of Arabidopsis thaliana

ARMAS, ALEJANDRO M.; BALPARDA, MANUEL; BUSI, MARIA VICTORIA; PAGANI, MARIA A.; DIEGO FABIAN GOMEZ CASATI

Virtual

Congreso; RAFV Conference 2021, XXXIII Argentinian meeting of Plant Physiology; 2021

Sociedad Argentina de Fisiología Vegetal (SAFV)

Several proteins including a cysteine desulfurase(AtNFS1) and frataxin (AtFH) are involved in the formation of Fe-S groups in Arabidopsismitochondria, specifically, in Fe and sulfur loading onto scaffold proteins,and the subsequent formation of the mature Fe-S cluster. We recently found thatthe small mitochondrial chaperone, AtISD11, and AtFH are positive regulatorsfor AtNFS1 activity. Moreover, when the three proteins were incubated together,a stronger attenuation of the Fenton reaction was observed compared to thatobserved with AtFH alone. Moreover, we found that these three proteinsphysically interact, and sequence alignment and docking studies showed thatseveral amino acid residues reported as critical for the interaction of theirhuman homologous are conserved. Our results suggest that AtFH, AtNFS1 andAtISD11 form a multiprotein complex that could be involved in different stagesof the iron–sulfur cluster (ISC) pathway in plant mitochondria.