ORC5

ORC5 is a protein that in humans is encoded by the ORC5 gene. This gene is a part of the origin recognition complex (ORC), which is highly conserved in eukaryotes and essential for the initiation of the DNA replication process. The ORC is a six-subunit complex, and ORC5 is one of its integral components, playing a crucial role in the formation of the pre-replication complex (pre-RC). The pre-RC is necessary for the replication of DNA in the S phase of the cell cycle.

Function

The origin recognition complex (ORC) is pivotal in the initiation of DNA replication. It binds to origins of replication and is involved in the formation of the pre-replication complex, which is essential for DNA replication to commence. ORC5, as a part of this complex, interacts with other ORC subunits to facilitate the correct assembly and function of the ORC. This interaction is crucial for the maintenance of genomic integrity and the prevention of DNA replication errors, which can lead to genomic instability and diseases such as cancer.

Gene

The ORC5 gene is located on chromosome 7 in humans. It encodes the ORC5 protein, which is composed of several hundred amino acids and has a conserved ATPase domain, indicating its role in energy-dependent processes within the cell.

Clinical Significance

Mutations in the ORC5 gene or dysregulation of the ORC5 protein can lead to replication stress and genomic instability, contributing to the development of cancer and other diseases. Research into ORC5 and its interactions within the ORC and with other proteins involved in DNA replication is ongoing, with the aim of understanding the mechanisms of replication initiation and its regulation. This knowledge could lead to the development of new therapeutic strategies for diseases associated with replication errors.

See Also

• DNA replication
• Origin recognition complex
• Cell cycle
• Genomic instability
• Cancer