UBQLN1
Encyclopedia
Ubiquilin-1 is a protein
that in humans is encoded by the UBQLN1 gene
.
Ubiquilins contain a N-terminal ubiquitin-like domain
and a C-terminal ubiquitin-associated domain. They physically associate with both proteasome
s and ubiquitin ligase
s, and thus are thought to functionally link the ubiquitination machinery to the proteasome to effect in vivo protein degradation.
Higher levels of ubiquilin-1 in the brain decreased malformation of the APP molecule which plays a key role in triggering Alzheimers disease. Conversly, lower levels of ubiquilin-1 in the brain were associated with increased malformation of APP.
(ubiquilin) shares high degree of similarity with related proteins in yeast, rat and frog.
with
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
that in humans is encoded by the UBQLN1 gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
.
Ubiquilins contain a N-terminal ubiquitin-like domain
Protein domain
A protein domain is a part of protein sequence and structure that can evolve, function, and exist independently of the rest of the protein chain. Each domain forms a compact three-dimensional structure and often can be independently stable and folded. Many proteins consist of several structural...
and a C-terminal ubiquitin-associated domain. They physically associate with both proteasome
Proteasome
Proteasomes are very large protein complexes inside all eukaryotes and archaea, and in some bacteria. In eukaryotes, they are located in the nucleus and the cytoplasm. The main function of the proteasome is to degrade unneeded or damaged proteins by proteolysis, a chemical reaction that breaks...
s and ubiquitin ligase
Ligase
In biochemistry, ligase is an enzyme that can catalyse the joining of two large molecules by forming a new chemical bond, usually with accompanying hydrolysis of a small chemical group dependent to one of the larger molecules...
s, and thus are thought to functionally link the ubiquitination machinery to the proteasome to effect in vivo protein degradation.
Possible Role In Preventing Alzheimers Disease
Ubiquilin has also been shown to modulate accumulation of presenilin proteins, and is found in lesions associated with Alzheimer's and Parkinson's disease. Two transcript variants encoding different isoforms have been found for this gene.Higher levels of ubiquilin-1 in the brain decreased malformation of the APP molecule which plays a key role in triggering Alzheimers disease. Conversly, lower levels of ubiquilin-1 in the brain were associated with increased malformation of APP.
Similarity to Non-human Proteins
Human ubiquitinUbiquitin
Ubiquitin is a small regulatory protein that has been found in almost all tissues of eukaryotic organisms. Among other functions, it directs protein recycling.Ubiquitin can be attached to proteins and label them for destruction...
(ubiquilin) shares high degree of similarity with related proteins in yeast, rat and frog.
Interactions
UBQLN1 has been shown to interactProtein-protein interaction
Protein–protein interactions occur when two or more proteins bind together, often to carry out their biological function. Many of the most important molecular processes in the cell such as DNA replication are carried out by large molecular machines that are built from a large number of protein...
with
- HERPUD1HERPUD1Homocysteine-responsive endoplasmic reticulum-resident ubiquitin-like domain member 1 protein is a protein that in humans is encoded by the HERPUD1 gene.-Interactions:HERPUD1 has been shown to interact with UBQLN1 and UBQLN2.-Further reading:...
, - MTORMammalian target of rapamycinThe mammalian target of rapamycin also known as mechanistic target of rapamycin or FK506 binding protein 12-rapamycin associated protein 1 is a protein which in humans is encoded by the FRAP1 gene...
, - P4HBP4HBProtein disulfide-isomerase is an enzyme that in humans is encoded by the P4HB gene.-Interactions:P4HB has been shown to interact with UBQLN1, ERO1LB and ERO1L.-Further reading:...
, - PSEN1PSEN1Presenilin-1 is a protein that in humans is encoded by the PSEN1 gene.- Function :Alzheimer's disease patients with an inherited form of the disease carry mutations in the presenilin proteins or the amyloid precursor protein...
- PSEN2PSEN2Presenilin-2 is a protein that in humans is encoded by the PSEN2 gene.- Function :Alzheimer's disease patients with an inherited form of the disease carry mutations in the presenilin proteins or the amyloid precursor protein...
, and - UBE3AUBE3AUbiquitin-protein ligase E3A also known as E6AP ubiquitin-protein ligase is an enzyme that in humans is encoded by the UBE3A gene. This enzyme is involved in targeting proteins for degradation within cells...
.