INSIG1
Encyclopedia
Insulin induced gene 1, also known as INSIG1, is a protein
which in humans is encoded by the INSIG1 gene
.
s regulate cholesterol homeostasis through liver X receptor (LXR
) and sterol regulatory element-binding protein (SREBP
) mediated signaling pathway. This gene is an insulin
-induced gene. It encodes an endoplasmic reticulum
(ER) membrane protein that plays a critical role in regulating cholesterol concentrations in cells. This protein binds to the sterol-sensing domains of SREBP cleavage-activating protein (SCAP
) and HMG CoA reductase, and is essential for the sterol-mediated trafficking of the two proteins. Alternatively spliced transcript variants encoding distinct isoforms have been observed.
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 INSIG1 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
OxysterolOxysterol
Oxysterols are oxidized derivatives of cholesterol, which are important in many biological processes, including cholesterol homeostasis, sphingolipid metabolism, platelet aggregation, apoptosis, and protein prenylation.Some examples of oxysterols include:*...
s regulate cholesterol homeostasis through liver X receptor (LXR
Liver X receptor
The liver X receptor is a member of the nuclear receptor family of transcription factors and is closely related to nuclear receptors such as the PPARs, FXR and RXR. Liver X receptors are important regulators of cholesterol, fatty acid, and glucose homeostasis...
) and sterol regulatory element-binding protein (SREBP
Sterol regulatory element binding protein
Sterol Regulatory Element-Binding Proteins are transcription factors that bind to the sterol regulatory element DNA sequence TCACNCCAC. Mammalian SREBPs are encoded by the genes SREBF1 and SREBF2. SREBPs belong to the basic-helix-loop-helix leucine zipper class of transcription factors...
) mediated signaling pathway. This gene is an 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....
-induced gene. It encodes an endoplasmic reticulum
Endoplasmic reticulum
The endoplasmic reticulum is an organelle of cells in eukaryotic organisms that forms an interconnected network of tubules, vesicles, and cisternae...
(ER) membrane protein that plays a critical role in regulating cholesterol concentrations in cells. This protein binds to the sterol-sensing domains of SREBP cleavage-activating protein (SCAP
SREBP cleavage activating protein
Sterol regulatory element-binding protein cleavage-activating protein, also known as SREBP cleavage-activating protein or SCAP is a protein that in humans is encoded by the SCAP gene....
) and HMG CoA reductase, and is essential for the sterol-mediated trafficking of the two proteins. Alternatively spliced transcript variants encoding distinct isoforms have been observed.