DNA methylation, a process by which methyl groups are added to DNA molecules, is essential for the maintenance of DNA and the overall health of an organism. Disruptions in the standard DNA methylation patterns can lead to immunodeficiency and diseases such as cancer. Helicase lymphoid-specific (HELLS) is an enzyme that facilitates DNA methylation by remodeling the nucleosome - the tightly packed structure of DNA wound around histone proteins.
The absence of HELLS or its activator, cell division cycle associated 7 (CDCA7) is known to be a factor that leads to the disruption of DNA methylation. Mutations in the genes that code for HELLS and CDCA7 cause rare disorder immunodeficiency, centromeric instability, and facial anomalies (ICF) syndrome. Understanding why CDCA7-HELLS is crucial for maintaining DNA methylation is vital for gaining insights into the mechanism of disorders such as ICF syndrome.
In a recent study published in Science Advances on August 23 2024, researchers have found that CDCA7 can recognize hemimethylation of DNA-;a state where one strand of the DNA's double helix is methylated but not the other-;and recruit HELLS to complete methylation of the DNA. The researchers found that the hemimethylation-sensing zinc finger (HMZF) of CDCA7 , which has been conserved throughout evolution, is key to its ability to perform maintenance DNA methylation. " We found that the CDCA7 gene, known as the causative gene of ICF syndrome, promotes DNA methylation by controlling th.