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Protein Page:
CTSA (human)

CTSA Protective protein appears to be essential for both the activity of beta-galactosidase and neuraminidase, it associates with these enzymes and exerts a protective function necessary for their stability and activity. This protein is also a carboxypeptidase and can deamidate tachykinins. Defects in CTSA are the cause of galactosialidosis (GSL). A lysosomal storage disease associated with a combined deficiency of beta-galactosidase and neuraminidase, secondary to a defect in cathepsin A. All patients have clinical manifestations typical of a lysosomal disorder, such as coarse facies, cherry red spots, vertebral changes, foam cells in the bone marrow, and vacuolated lymphocytes. Three phenotypic subtypes are recognized. The early infantile form is associated with fetal hydrops, edema, ascites, visceromegaly, skeletal dysplasia, and early death. The late infantile type is characterized by hepatosplenomegaly, growth retardation, cardiac involvement, and a normal or mildly affected mental state. The juvenile/adult form is characterized by myoclonus, ataxia, angiokeratoma, mental retardation, neurologic deterioration, absence of visceromegaly, and long survival. Belongs to the peptidase S10 family. Note: This description may include information from UniProtKB.
Protein type: EC; Endoplasmic reticulum; Mitochondrial; Protease
Chromosomal Location of Human Ortholog: 20q13.1
Cellular Component: endoplasmic reticulum; intracellular membrane-bound organelle; lysosomal lumen; membrane; nucleoplasm
Molecular Function: carboxypeptidase activity; enzyme activator activity; exo-alpha-sialidase activity; serine carboxypeptidase activity
Biological Process: glycosphingolipid metabolic process; intracellular protein transport; proteolysis; proteolysis involved in cellular protein catabolic process; regulation of protein stability
Disease: Galactosialidosis
Reference #:  P10619 (UniProtKB)
Alt. Names/Synonyms: beta-galactosidase 2; beta-galactosidase protective protein; Carboxypeptidase C; Carboxypeptidase L; Cathepsin A; CTSA; GLB2; GSL; Lysosomal protective protein; Lysosomal protective protein 20 kDa chain; Lysosomal protective protein 32 kDa chain; NGBE; PPCA; PPGB; Protective protein cathepsin A; Protective protein for beta-galactosidase
Gene Symbols: CTSA
Molecular weight: 54,466 Da
Basal Isoelectric point: 6.16  Predict pI for various phosphorylation states
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Protein Structure Not Found.
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