Ubiquitination is an important mechanism through which three classes of enzymes act in concert to target short-lived or abnormal proteins for destruction. The three classes of enzymes involved in ubiquitination are the ubiquitin-activating enzymes (E1s), the ubiquitin-conjugating enzymes (E2s) and the ubiquitin-protein ligases (E3s). Ubr2 (Ubiquitin-protein ligase E3-alpha-2), also known as N-recognin-2, is a 1755 amino acid protein that contains one UBR-type zinc finger and one RING-type zinc finger. Participating in protein modification events within the N-end rule pathway, Ubr2 functions as an E3 ubiquitin-protein ligase that recognizes and binds proteins that contain destabilizing N-terminal residues, thereby leading to their ubiquitination and subsequent degradation. Mice lacking Ubr2 are infertile due to defects in male meiosis.
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. Plays a critical role in chromatin inactivation and chromosome-wide transcriptional silencing during meiosis via ubiquitination of histone H2A. Binds leucine and is a negative regulator of the leucine-mTOR signaling pathway, thereby controlling cell growth.
Subunit:
Interacts with UBE2B; promotes the UBE2B-H2A interaction and the ubiquitination of histone H2A by UBE2B and UBR2 Interacts with RECQL4.
Subcellular Location:
Nucleus. Note=Associated with chromatin during meiosis.
Tissue Specificity:
Broadly expressed, with highest levels in skeletal muscle, kidney and pancreas. Present in acinar cells of the pancreas (at protein level).
Similarity:
Belongs to the UBR1 family.
Contains 1 RING-type zinc finger.
Contains 1 UBR-type zinc finger.
SWISS:
Q8IWV8
Gene ID:
23304
Database links:
Entrez Gene: 23304 Human
Entrez Gene: 224826 Mouse
Omim: 609134 Human
SwissProt: Q8IWV8 Human
SwissProt: Q6WKZ8 Mouse
Unigene: 529925 Human
Unigene: 28234 Mouse
|
|
