High impact information on Orc5

• The six-subunit origin recognition complex (ORC) is a DNA replication initiator protein in eukaryotes that defines the localization of the origins of replication [1].
• We report here that the smallest Drosophila ORC subunit, Orc6, is a DNA binding protein that is necessary for the DNA binding and DNA replication functions of ORC [1].
• RT-PCR analyses of RNA purified from E2f2 mutant follicle cells indicate an increase in the level of Orc5 mRNA relative to wild type [2].
• A second divergent promoter region (P2) controls the expression of the orc5 and sop2 genes [3].
• Its role in controlling the expression of the pol gamma-beta and orc5 genes establishes a common regulatory mechanism linking nuclear and mitochondrial DNA replication [3].

Biological context of Orc5

• We propose that the abnormal subcellular distribution and segregation of ORC proteins in AD might compromise their physiological function in gene silencing and plasticity [4].
• ORC subunits might, thus, provide a direct molecular link between synaptic plasticity, DNA replication and cell death [4].
• ORC subunits in the mammalian brain and their homologes in Drosophila, however, have further been implicated in the regulation of structural neuronal plasticity and cognitive function [4].

References