TOMM40
Encyclopedia
Translocase of outer mitochondrial membrane 40 homolog (yeast), also known as TOMM40, is a protein
which in humans is encoded by the TOMM40 gene
.
into mitochondria. More precisely, TOMM40 is the channel-forming subunit of a translocase
of the mitochondrial outer membrane (TOM
) that is essential for protein transport into mitochondria
.
. One study has found that TOMM40 appears twice as often in people with Alzheimer's disease than those without it. Because TOMM40 is located on chromosome 19, and is closely adjacent to APOE
, another gene known to be associated with Alzheimer's, another study has suggested that the statistically significant correlation of TOMM40 with Alzheimer's is due to linkage disequilibrium
.
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...
which in humans is encoded by the TOMM40 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...
.
Function
TOMM40 codes for a protein that is embedded into outer membranes of mitochondria and is required for the movement of proteinsMembrane transport
In cellular biology the term membrane transport refers to the collection of mechanisms that regulate the passage of solutes such as ions and small molecules through biological membranes namely lipid bilayers that contain proteins embedded in them...
into mitochondria. More precisely, TOMM40 is the channel-forming subunit of a translocase
Translocase
Translocase is a general term for an enzyme that assists in moving another molecule, usually across a membrane.Translocases are most common secretion system in Gram positive bacteria.Examples include:...
of the mitochondrial outer membrane (TOM
Outer mitochondrial membrane
thumb|300px|Mitochondria structure :1) [[Inner membrane]]2) Outer membrane3) [[Crista]]4) [[Matrix |Matrix]]The outer mitochondrial membrane, which encloses the entire organelle, has a protein-to-phospholipid ratio similar to the eukaryotic plasma membrane...
) that is essential for protein transport into mitochondria
Mitochondrion
In cell biology, a mitochondrion is a membrane-enclosed organelle found in most eukaryotic cells. These organelles range from 0.5 to 1.0 micrometers in diameter...
.
Clinical significance
In humans, certain alleles of this gene have been statistically associated with an increased risk of developing late-onset Alzheimer's DiseaseAlzheimer's disease
Alzheimer's disease also known in medical literature as Alzheimer disease is the most common form of dementia. There is no cure for the disease, which worsens as it progresses, and eventually leads to death...
. One study has found that TOMM40 appears twice as often in people with Alzheimer's disease than those without it. Because TOMM40 is located on chromosome 19, and is closely adjacent to APOE
Apolipoprotein E
Apolipoprotein E is a class of apolipoprotein found in the chylomicron and IDLs that binds to a specific receptor on liver cells and peripheral cells. It is essential for the normal catabolism of triglyceride-rich lipoprotein constituents.-Function:...
, another gene known to be associated with Alzheimer's, another study has suggested that the statistically significant correlation of TOMM40 with Alzheimer's is due to linkage disequilibrium
Linkage disequilibrium
In population genetics, linkage disequilibrium is the non-random association of alleles at two or more loci, not necessarily on the same chromosome. It is also referred to as to as gametic phase disequilibrium , or simply gametic disequilibrium...
.