Fusion protein of two essential components of the cytosolic iron-sulfur (Fe/S) protein assembly (CIA) machinery. Required for maturation of extramitochondrial Fe-S proteins. May form a heterotetramer with nubp35, functioning as a Fe-S scaffold complex, mediating the de novo assembly of an Fe-S cluster and its transfer to target apoproteins (By similarity). Binds 4 [4Fe-4S] clusters per heterotetramer. Contains two stable clusters in the N-termini of nbp35 and two labile, bridging clusters between subunits of the nbp35-SPAC806.02c heterotetramer. Heterotetramer of 2 nbp35 and 2 SPAC806.02c chains. Results from a fusion of two genes coding for two proteins which both play a role in assembly of Fe-S clusters in other species (CFD1 and CIA1 in S.cerevisiae). In the N-terminal section; belongs to the Mrp/NBP35 ATP-binding proteins family. NUBP2/CFD1 subfamily. In the C-terminal section; belongs to the WD repeat CIA1 family.