Throughout the cytosol and the nucleus, the delivery of tightly bound sulfur and iron clusters is essential for cellular processes, including DNA replication and repair, ribosome biogenesis, and regulation of proteins. Various enzymes, like helicases, also require these clusters to function. When clusters, called cofactors, aren’t delivered correctly, the client proteins cannot function properly; defects in the cytosolic iron-sulfur cluster assembly (CIA) pathway can lead to human disease.
The molecular machinery responsible for transferring these clusters, called the CIA targeting complex, is not the only molecular machinery responsible for conveying cofactors; other known examples often have only one or two clients. By contrast, the CIA targeting complex can transfer cofactors to more than 30 known clients.
