ID:GLSK_HUMAN DESCRIPTION: RecName: Full=Glutaminase kidney isoform, mitochondrial; Short=GLS; EC=3.5.1.2; AltName: Full=K-glutaminase; AltName: Full=L-glutamine amidohydrolase; Flags: Precursor; FUNCTION: Catalyzes the first reaction in the primary pathway for the renal catabolism of glutamine. Plays a role in maintaining acid-base homeostasis. Regulates the levels of the neurotransmitter glutamate in the brain. Isoform 2 lacks catalytic activity. CATALYTIC ACTIVITY: L-glutamine + H(2)O = L-glutamate + NH(3). ENZYME REGULATION: Isoform 1 and isoform 3 are activated by phosphate. Inhibited by BPTES. BPTES binds between subunits and favors dissociation of the tetramer into dimers. BIOPHYSICOCHEMICAL PROPERTIES: Kinetic parameters: KM=1.9 mM for glutamine (isoform 1); KM=1.4 mM for glutamine (isoform 3); SUBUNIT: Heterotetramer. Interacts with ATCAY; the interaction is direct and may control GLS localization, negatively regulating its activity. SUBCELLULAR LOCATION: Isoform 1: Cytoplasm, cytosol. SUBCELLULAR LOCATION: Isoform 3: Mitochondrion. TISSUE SPECIFICITY: Isoform 1 and isoform 3 are detected in brain cortex. Isoform 3 is highly expressed in astrocytoma, ganglioglioma and ependymoma. Isoform 1 is highly expressed in brain and kidney, but not detected in liver. Isoform 3 is highly expressed in heart and pancreas, detected at lower levels in placenta, lung, pancreas and kidney, but is not detected in liver. Isoform 2 is expressed in cardiac and skeletal muscle. SIMILARITY: Belongs to the glutaminase family. SIMILARITY: Contains 2 ANK repeats. CAUTION: Isoform 3 is predicted to be expressed at very low levels due to a premature stop codon in the mRNA, leading to nonsense- mediated mRNA decay (PubMed:14759258), but has been shown to be well expressed (PubMed:17940881 and PubMed:11015561) and the encoded protein is detected in mitochondria (PubMed:22228304). SEQUENCE CAUTION: Sequence=BAA74861.2; Type=Erroneous initiation; Note=Translation N-terminally shortened;
Protein Domain and Structure Information
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