receptor accessory protein 1
The REEP1 gene provides instructions for making a protein called receptor expression-enhancing protein 1 (REEP1), which is found in nerve cells (neurons) in the brain and spinal cord. The REEP1 protein is located within cell compartments called mitochondria, which are the energy-producing centers in cells, and the endoplasmic reticulum, which helps with protein processing and transport.
The REEP1 protein plays a role in forming the network of tubules that make up the structure of the endoplasmic reticulum, regulating its size and determining how many proteins it can process. As part of its role in the endoplasmic reticulum, the REEP1 protein enhances the activity of certain other proteins called G protein-coupled receptors. These receptor proteins are eventually embedded within the outer membrane of cells, where they relay chemical signals from outside the cell to the interior of the cell.
The function of the REEP1 protein in the mitochondria is unknown.
Genetics Home Reference provides information about distal hereditary motor neuropathy, type V.
At least 44 mutations in the REEP1 gene have been found to cause spastic paraplegia type 31. This condition is characterized by muscle stiffness (spasticity) and paralysis of the lower limbs (paraplegia) caused by degeneration of nerve cells (neurons) that trigger muscle movement. Most of the REEP1 gene mutations that cause this condition insert or remove small pieces of DNA from the gene or alter the way the gene's instructions are used to make the protein. These mutations often result in a short, nonfunctional protein that is quickly broken down. As a result, there is a reduction in functional REEP1 protein.
It is unclear how REEP1 gene mutations lead to the signs and symptoms of spastic paraplegia type 31. Researchers have shown that mitochondria in cells of affected individuals are less able to produce energy, which may contribute to the death of neurons and lead to the progressive movement problems of spastic paraplegia type 31; however, the exact mechanism that causes this condition is unknown.
- receptor expression-enhancing protein 1