TBC1D4
Encyclopedia
TBC1 domain family member 4 is a protein
that in humans is encoded by the TBC1D4 gene
.
The 160 kD protein product was first discovered in a screen for novel substrates of the serine-threonine kinase Akt
, which phosphorylates AS160 after insulin stimulation. Insulin
stimulation of fat and muscle cells results in translocation of the glucose transporter GLUT4
to the plasma membrane, and this translocation process is dependent on phosphorylation of AS160. The role of AS160 in GLUT4 translocation is mediated by its GTPase activating domain and interactions with Rab proteins in vesicle formation, increasing GLUT4 translocation when its GTPase activity is inhibited by Akt phosphorylation. Specifically, this inhibition activates RAB2A
, RAB8A
, RAB10
and RAB14
.
AS160 also contains a calmodulin-binding domain, and this domain mediates phosphorylation-independent glucose uptake in muscle cells.
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 TBC1D4 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...
.
The 160 kD protein product was first discovered in a screen for novel substrates of the serine-threonine kinase Akt
AKT
Akt, also known as Protein Kinase B , is a serine/threonine protein kinase that plays a key role in multiple cellular processes such as glucose metabolism, cell proliferation, apoptosis, transcription and cell migration.-Family members:...
, which phosphorylates AS160 after insulin stimulation. Insulin
Insulin
Insulin is a hormone central to regulating carbohydrate and fat metabolism in the body. Insulin causes cells in the liver, muscle, and fat tissue to take up glucose from the blood, storing it as glycogen in the liver and muscle....
stimulation of fat and muscle cells results in translocation of the glucose transporter GLUT4
GLUT4
Glucose transporter type 4, also known as GLUT4, is a protein that in humans is encoded by the GLUT4 gene. GLUT4 is the insulin-regulated glucose transporter found in adipose tissues and striated muscle that is responsible for insulin-regulated glucose translocation into the cell...
to the plasma membrane, and this translocation process is dependent on phosphorylation of AS160. The role of AS160 in GLUT4 translocation is mediated by its GTPase activating domain and interactions with Rab proteins in vesicle formation, increasing GLUT4 translocation when its GTPase activity is inhibited by Akt phosphorylation. Specifically, this inhibition activates RAB2A
RAB2A
Ras-related protein Rab-2A is a protein that in humans is encoded by the RAB2A gene.-Further reading:...
, RAB8A
RAB8A
Ras-related protein Rab-8A is a protein that in humans is encoded by the RAB8A gene.-Interactions:RAB8A has been shown to interact with Optineurin and MAP4K2.-Further reading:...
, RAB10
RAB10
Ras-related protein Rab-10 is a protein that in humans is encoded by the RAB10 gene.-Further reading:...
and RAB14
RAB14
Ras-related protein Rab-14 is a protein that in humans is encoded by the RAB14 gene.-Further reading:...
.
AS160 also contains a calmodulin-binding domain, and this domain mediates phosphorylation-independent glucose uptake in muscle cells.