ORC1

Quality 0.50 · 1 view · Updated 2 months ago

Protein-coding gene in the species Homo sapiens

title: "ORC1" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public description: "Protein-coding gene in the species Homo sapiens" topic_path: "uncategorized" source: "https://en.wikipedia.org/wiki/ORC1" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Protein-coding gene in the species Homo sapiens ::

Origin recognition complex subunit 1 is a protein that in humans is encoded by the ORC1 gene. It is closely related to CDC6, and both are the same protein in archaea.

Function

The origin recognition complex (ORC) is a highly conserved six subunits protein complex essential for the initiation of the DNA replication in eukaryotic cells. Studies in yeast demonstrated that ORC binds specifically to origins of replication and serves as a platform for the assembly of the pre-replication complex, which includes additional initiation factors such as Cdc6 and Mcm proteins. The protein encoded by this gene is the largest subunit of the origin recognition complex. While other ORC subunits are stable throughout the cell cycle, the levels of this protein vary during the cell cycle, which has been shown to be controlled by ubiquitin-mediated proteolysis after initiation of DNA replication. This protein is found to be selectively phosphorylated during mitosis. It is also reported to interact with MYST histone acetyltransferase 2 (MYST2/HBO1), a protein involved in control of transcription silencing.

Interactions

ORC1 has been shown to interact with:

CDC45-related protein and
CDC6,
Cell division cycle 7-related protein kinase,
Cyclin-dependent kinase 2,
MCM2,
MCM4,
MCM6,
MCM7,
MYST2,
ORC2,
ORC4,
ORC5, and
SKP2.

References

(September 1996). "Mapping of the human homologue (ORC1L) of the yeast origin recognition complex subunit 1 gene to chromosome band 1p32". Genomics.
"Entrez Gene: ORC1L origin recognition complex, subunit 1-like (yeast)".
(January 2017). "Diversity of DNA Replication in the Archaea". Genes.
(May 1998). "Human CDC6/Cdc18 associates with Orc1 and cyclin-cdk and is selectively eliminated from the nucleus at the onset of S phase". Molecular and Cellular Biology.
(August 1999). "Histone acetyltransferase HBO1 interacts with the ORC1 subunit of the human initiator protein". The Journal of Biological Chemistry.
(March 2003). "Interaction and assembly of murine pre-replicative complex proteins in yeast and mouse cells". Journal of Molecular Biology.
(March 2002). "Nuclear organization of DNA replication initiation proteins in mammalian cells". The Journal of Biological Chemistry.
(July 2001). "Assembly of the human origin recognition complex". The Journal of Biological Chemistry.
(March 2002). "Human origin recognition complex large subunit is degraded by ubiquitin-mediated proteolysis after initiation of DNA replication". Molecular Cell.

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::