Ciao2b is a subunit of the cytosolic iron-sulfur cluster assembly (CIA) targeting complex (CTC). The CTC is crucial for inserting iron-sulfur (Fe-S) clusters into cytosolic and nuclear client proteins, with Fe-S proteins being involved in essential cellular functions such as DNA replication and repair [2].

In Caenorhabditis elegans, the deletion of CIAO-2B leads to a loss of DOG-1/BRIP1 stability and repair functions, increasing DNA damage sensitivity. This indicates that CIAO-2B is vital for the proper functioning of DOG-1, which is critical for genome integrity [1]. Also, in human studies, crystal structures show that CIAO2B is centrally located in the CTC, bridging CIAO1 and the client adaptor protein MMS19, suggesting its importance in the molecular mechanisms of client protein recognition [2].

In conclusion, CIAO2B is essential for the stability and function of proteins like DOG-1 in maintaining genome integrity. Its role in the CTC structure provides insights into Fe-S cluster transfer to client proteins involved in DNA metabolism. Understanding CIAO2B through model-based research, such as in C. elegans, helps in comprehending its contribution to biological processes related to DNA replication, repair, and overall genome stability [1,2].

References:

1. Li, Xiao, Perdomo, Ivette Maria Menendez, Rodrigues Alves Barbosa, Victoria, Diao, Catherine, Tarailo-Graovac, Maja. . The critical role of the iron-sulfur cluster and CTC components in DOG-1/BRIP1 function in Caenorhabditis elegans. In Nucleic acids research, 52, 9586-9595. doi:10.1093/nar/gkae617. https://pubmed.ncbi.nlm.nih.gov/39011897/

2. Kassube, Susanne A, Thomä, Nicolas H. 2020. Structural insights into Fe-S protein biogenesis by the CIA targeting complex. In Nature structural & molecular biology, 27, 735-742. doi:10.1038/s41594-020-0454-0. https://pubmed.ncbi.nlm.nih.gov/32632277/