SPG7, paraplegin matrix AAA peptidase subunit
The SPG7 gene provides instructions for producing a protein called paraplegin, which is a member of the AAA protein family. This protein family plays a role in many cellular activities, including regulation of cell components and proteins. Located within the inner membrane of the energy-producing centers of cells (mitochondria), paraplegin is one of the proteins that form a complex called the m-AAA protease. The m-AAA protease is responsible for assembling ribosomes (cellular structures that process the cell's genetic instructions to create proteins) and removing nonfunctional proteins in the mitochondria.
More than 100 mutations in the SPG7 gene have been found to cause spastic paraplegia type 7. This condition is characterized by muscle weakness, progressive muscle stiffness (spasticity) in the legs, and difficulty walking. Most of the SPG7 gene mutations change single protein building blocks (amino acids) in the paraplegin protein. When paraplegin is altered, it cannot organize with other proteins within the mitochondria to form the m-AAA protease. The buildup of unusable proteins in nerve cells, caused by the nonfunctional m-AAA protease, can impair mitochondrial functioning and diminish nerve cell signaling, leading to the major signs and symptoms of spastic paraplegia type 7.
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- cell adhesion regulator
- paraplegin, isoform 1
- spastic paraplegia 7
- spastic paraplegia 7 (pure and complicated autosomal recessive)