ORC4L overexpression 293T lysate (whole cell)

Supplementary information

This supplementary information is collated from multiple sources and compiled automatically.

The origin recognition complex subunit 4-like (ORC4L) also known simply as ORC4 is a mechanically important player in the initiation of DNA replication. ORC4 typically has a molecular mass of approximately 50 kDa. It is highly expressed in cells that are actively dividing especially within the nucleus where replication origins are located. The protein forms part of the larger origin recognition complex (ORC) which is important for marking the starting points for DNA replication across eukaryotic organisms.

Biological function summary

ORC4 plays a central role in recognizing replication origins and acts as an anchor for the assembly of other necessary replication proteins. It is one of six subunits that comprise the ORC complex. This protein complex binds to origins of replication in DNA unwinds the double helix and recruits additional factors required for the formation of the pre-replicative complex. The presence of ORC4 is essential in ensuring that DNA replication occurs once and only once per cell cycle preventing genomic instability.

Pathways

Several cellular processes depend on the correct functioning of ORC4. In cell cycle regulation ORC4 is integral to the DNA replication checkpoint which ensures DNA is not damaged before it is duplicated. ORC4 interacts with other replication factors like CDC6 and MCM2-7 helicase to initiate and regulate the replication process. Its activity influences key pathways such as the p53-dependent DNA damage response where ORC4 can affect decisions related to cell cycle arrest or apoptosis.

ORC4 dysregulation links to genomic instability which is a hallmark in the development of cancer. Altered levels or mutations in ORC4 contribute to an increased susceptibility to oncogenesis with links to various cancers such as those of the breast and colon. The BRCA1 protein known for its role in maintaining genomic stability and DNA repair often shows interactions with ORC4 during such disease states highlighting their interconnected roles in cancer-related pathways.