Acts as a mitochondrial iron-sulfur (Fe-S) cluster assembly factor that facilitates (Fe-S) cluster insertion into a subset of mitochondrial proteins. Probably acts together with NFU1 (PubMed:27532772). Interacts with NFU1 (PubMed:27532772). Widely expressed. The disease is caused by variants affecting the gene represented in this entry. Belongs to the BolA/IbaG family. Was initially reported to be secreted via a non-classical export pathway (PubMed:18548201). It was however later shown that it localizes to mitochondria, in agreement with other members of the family (PubMed:22746225).