The human gene UBR1 encodes the enzyme ubiquitin-protein ligase E3 component n-recognin 1.

The N-end rule pathway is one proteolytic pathway of the ubiquitin system. The recognition component of this pathway, encoded by this gene, binds to a destabilizing N-terminal residue of a substrate protein and participates in the formation of a substrate-linked multiubiquitin chain. This leads to the eventual degradation of the substrate protein. The protein described in this record has a RING-type zinc finger and a UBR-type zinc finger. Mutations in this gene have been associated with Johanson-Blizzard syndrome. [provided by RefSeq, Jul 2008]. Publication Note: This RefSeq record includes a subset of the publications that are available for this gene. Please see the Gene record to access additional publications.
Function: E3 ubiquitin-protein ligase which is a component of the N-end rule pathway. Recognizes and binds to proteins bearing specific N-terminal residues that are destabilizing according to the N-end rule, leading to their ubiquitination and subsequent degradation. May be involved in pancreatic homeostasis. Binds leucine and is a negative regulator of the leucine-mTOR signaling pathway, thereby controlling cell growth.