Glutamine Synthetase (GLUL) Active Protein

The protein encoded by this gene belongs to the glutamine synthetase family. It catalyzes the synthesis of glutamine from glutamate and ammonia in an ATP-dependent reaction. This protein plays a role in ammonia and glutamate detoxification, acid-base homeostasis, cell signaling, and cell proliferation. Glutamine is an abundant amino acid, and is important to the biosynthesis of several amino acids, pyrimidines, and purines. Mutations in this gene are associated with congenital glutamine deficiency, and overexpression of this gene was observed in some primary liver cancer samples. There are six pseudogenes of this gene found on chromosomes 2, 5, 9, 11, and 12. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2014]

GLUL: This enzyme has 2 functions: it catalyzes the production of glutamine and 4-aminobutanoate (gamma-aminobutyric acid, GABA), the latter in a pyridoxal phosphate-independent manner. Essential for proliferation of fetal skin fibroblasts. Defects in GLUL are the cause of congenital systemic glutamine deficiency (CSGD). CSGD is a rare developmental disorder with severe brain malformation resulting in multi-organ failure and neonatal death. Glutamine is largely absent from affected patients serum, urine and cerebrospinal fluid. Belongs to the glutamine synthetase family.

Protein type: Amino Acid Metabolism - alanine, aspartate and glutamate; Amino Acid Metabolism - arginine and proline; EC 4.1.1.15; EC 6.3.1.2; Energy Metabolism - nitrogen; Ligase

Chromosomal Location of Human Ortholog: 1q25.3

Cellular Component: cytosol; mitochondrion; nucleus

Molecular Function: glutamate-ammonia ligase activity; identical protein binding; protein binding

Biological Process: amino acid biosynthetic process; cell proliferation; glutamate catabolic process; glutamine biosynthetic process; neurotransmitter uptake

Disease: Glutamine Deficiency, Congenital