E3 ubiquitin-protein ligase synoviolin is an enzyme that in humans is encoded by the SYVN1 gene. [5] [6]
This gene encodes a protein involved in endoplasmic reticulum (ER)-associated degradation. The encoded protein removes unfolded proteins, accumulated during ER stress, by retrograde transport to the cytosol from the ER. This protein also uses the ubiquitin-proteasome system for additional degradation of unfolded proteins. This gene and the mitochondrial ribosomal protein L49 gene use in their respective 3' UTRs some of the same genomic sequence. Sequence analysis identified two transcript variants that encode different isoforms. [6]
Ubiquitin is a small regulatory protein found in most tissues of eukaryotic organisms, i.e., it is found ubiquitously. It was discovered in 1975 by Gideon Goldstein and further characterized throughout the late 1970s and 1980s. Four genes in the human genome code for ubiquitin: UBB, UBC, UBA52 and RPS27A.
Calnexin (CNX) is a 67kDa integral protein (that appears variously as a 90kDa, 80kDa, or 75kDa band on western blotting depending on the source of the antibody) of the endoplasmic reticulum (ER). It consists of a large (50 kDa) N-terminal calcium-binding lumenal domain, a single transmembrane helix and a short (90 residues), acidic cytoplasmic tail.
Endoplasmic-reticulum-associated protein degradation (ERAD) designates a cellular pathway which targets misfolded proteins of the endoplasmic reticulum for ubiquitination and subsequent degradation by a protein-degrading complex, called the proteasome.
E3 ubiquitin-protein ligase SIAH1 is an enzyme that in humans is encoded by the SIAH1 gene.
Probable G-protein coupled receptor 37 is a protein that in humans is encoded by the GPR37 gene.
Valosin-containing protein (VCP) or transitional endoplasmic reticulum ATPase also known as p97 in mammals and CDC48 in S. cerevisiae, is an enzyme that in humans is encoded by the VCP gene. The TER ATPase is an ATPase enzyme present in all eukaryotes and archaebacteria. Its main function is to segregate protein molecules from large cellular structures such as protein assemblies, organelle membranes and chromatin, and thus facilitate the degradation of released polypeptides by the multi-subunit protease proteasome.
E3 ubiquitin-protein ligase SIAH2 is an enzyme that in humans is encoded by the SIAH2 gene.
Autocrine motility factor receptor, isoform 2 is a protein that in humans is encoded by the AMFR gene.
Ubiquitin-conjugating enzyme E2 D2 is a protein that in humans is encoded by the UBE2D2 gene.
Homocysteine-responsive endoplasmic reticulum-resident ubiquitin-like domain member 1 protein is a protein that in humans is encoded by the HERPUD1 gene.
Selenoprotein S, also known as SELS, is a human gene.
Ubiquitin-conjugating enzyme E2 G2 is a protein that in humans is encoded by the UBE2G2 gene.
Nuclear factor erythroid 2-related factor 1 (Nrf1) also known as nuclear factor erythroid-2-like 1 (NFE2L1) is a protein that in humans is encoded by the NFE2L1 gene. Since NFE2L1 is referred to as Nrf1, it is often confused with nuclear respiratory factor 1 (Nrf1).
Derlin-1 also known as degradation in endoplasmic reticulum protein 1 is a membrane protein that in humans is encoded by the DERL1 gene. Derlin-1 is located in the membrane of the endoplasmic reticulum (ER) and is involved in retrotranslocation of specific misfolded proteins and in ER stress. Derlin-1 is widely expressed in thyroid, fat, bone marrow and many other tissues. The protein belongs to the Derlin-family proteins consisting of derlin-1, derlin-2 and derlin-3 that are components in the endoplasmic reticulum-associated protein degradation (ERAD) pathway. The derlins mediate degradation of misfolded lumenal proteins within ER, and are named ‘der’ for their ‘Degradation in the ER’. Derlin-1 is a mammalian homologue of the yeast DER1 protein, a protein involved in the yeast ERAD pathway. Moreover, derlin-1 is a member of the rhomboid-like clan of polytopic membrane proteins.
Protein transport protein Sec61 subunit alpha isoform 1 is a protein that in humans is encoded by the SEC61A1 gene.
Ubiquitin-conjugating enzyme E2 G1 is a protein that in humans is encoded by the UBE2G1 gene.
PNGase also known as N-glycanase 1 or peptide-N(4)-(N-acetyl-beta-glucosaminyl)asparagine amidase is an enzyme that in humans is encoded by the NGLY1 gene. PNGase is a de-N-glycosylating enzyme that removes N-linked or asparagine-linked glycans (N-glycans) from glycoproteins. More specifically, NGLY1 catalyzes the hydrolysis of the amide bond between the innermost N-acetylglucosamine (GlcNAc) and an Asn residue on an N-glycoprotein, generating a de-N-glycosylated protein, in which the N-glycoylated Asn residue is converted to asp, and a 1-amino-GlcNAc-containing free oligosaccharide. Ammonia is then spontaneously released from the 1-amino GlcNAc at physiological pH (<8), giving rise to a free oligosaccharide with an N,N’-diacetylchitobiose structure at the reducing end.
Ubiquitin-conjugating enzyme E2 J1 is a protein that in humans is encoded by the UBE2J1 gene.
Translocation protein SEC63 homolog is a protein that in humans is encoded by the SEC63 gene.
E3 ubiquitin-protein ligase MARCH6 is an enzyme that in humans is encoded by the MARCH6 gene.