CDC45 is an essential component of the CDC45-MCM-GINS (CMG) helicase complex, which serves as the core replicative machinery for eukaryotic DNA replication 1. The CMG complex functions as the central molecular machine that unwinds template DNA during replication, with the replisome organized around this helicase 1. CDC45 is required for the initiation of chr22 DNA replication and plays a crucial role in CMG assembly 2. The protein is involved in replication fork progression, with structural studies revealing its detailed interactions within the human replisome containing CMG, DNA polymerase Ξ΅, and accessory proteins like TIMELESS-TIPIN and CLASPIN 3. CDC45 participates in specialized DNA repair processes, including the resolution of G-quadruplex structures during replication, where the CMG helicase can stall at these secondary structures on the leading strand 4. Disease associations include Meier-Gorlin syndrome 7, and CDC45 expression has been implicated as a biomarker in acute respiratory distress syndrome 5. The gene's promoter contains regulatory elements responsive to transcriptional activation, including GGAA motifs that can be induced by compounds like trans-resveratrol 6.