Component of the cytosolic iron-sulfur (Fe/S) protein assembly (CIA) machinery. Required for maturation of extramitochondrial Fe-S proteins. The NUBP1-NUBP2 heterotetramer forms a Fe-S scaffold complex, mediating the de novo assembly of an Fe-S cluster and its transfer to target apoproteins. Negatively regulates cilium formation and structure. {ECO:0000250|UniProtKB:Q9R061, ECO:0000255|HAMAP- Rule:MF_03039}. This is the function of ENSG00000095906 (NUBP2, NUBP iron-sulfur cluster assembly factor 2, cytosolic).