This article was accepted into the corpus but its outbound wikilinks were never NER-processed — typical at the deepest BFS hop or when the run's entity cap was reached. No expansion funnel to show.
| GLS1 | |
|---|---|
| Name | Glutaminase kidney isoform (GLS1) |
| Organism | Homo sapiens |
| Length | ~616 amino acids |
| Location | Chromosome 2 |
| Function | Glutamine hydrolysis to glutamate and ammonia |
| Synonyms | KGA, glutaminase kidney isoform |
GLS1 GLS1 encodes a mitochondrial glutaminase enzyme that catalyzes the hydrolysis of Glutamine to glutamate and ammonia, contributing to cellular TCA cycle anaplerosis and neurotransmitter pools. The gene product is implicated in metabolic adaptation in tissues including Brain, Kidney, and Immune system compartments, and has been studied in contexts ranging from Cancer metabolism to Neurodegenerative disease and Ischemia.
The protein arises from a locus on chromosome 2 and is expressed as multiple isoforms generated by alternative splicing and post‑translational processing. Studies across model organisms such as Mus musculus, Rattus norvegicus, and Drosophila melanogaster have elucidated conserved roles in cellular bioenergetics, synaptic transmission, and redox balance. The enzyme has been characterized structurally and biochemically in investigations led by laboratories associated with institutions like Massachusetts Institute of Technology, Harvard Medical School, and research consortia focused on Cancer metabolism.
The locus spans multiple exons on chromosome 2 and produces transcripts that encode the mitochondrial matrix enzyme. The primary translation product contains an N‑terminal mitochondrial targeting sequence cleaved after import, yielding a mature catalytic domain whose fold resembles that of the family typified by bacterial glutaminases studied in Escherichia coli and Bacillus subtilis. High‑resolution structures obtained by groups at European Molecular Biology Laboratory and Brookhaven National Laboratory reveal a homotetrameric assembly with active sites located at subunit interfaces; these structures informed mutational analyses published in journals associated with Nature Publishing Group and Cell Press.
Expression is tissue‑specific, with high abundance in Brain, Kidney, Liver, and activated T lymphocyte subsets. Transcriptional control involves promoters responsive to factors such as c-Myc, p53, and HIF-1α in hypoxia, with epigenetic modulation reported in studies from groups at Johns Hopkins University and University of Cambridge. Post‑translational regulation includes phosphorylation by kinases like Protein kinase A and allosteric activation by inorganic phosphate, as shown in biochemical work from laboratories at Max Planck Society and Cold Spring Harbor Laboratory.
The enzyme catalyzes glutamine hydrolysis to produce glutamate and ammonium, feeding into α-Ketoglutarate formation through transamination or dehydrogenation by Glutamate dehydrogenase. Kinetic studies performed using methods standard at American Chemical Society meetings demonstrate Michaelis–Menten behavior with regulation by substrate availability and feedback from downstream metabolites. Mechanistic proposals, refined by crystallography and mutagenesis at institutions including University of Oxford and Stanford University, indicate a catalytic cysteine and a conserved glutamate residue coordinate proton transfer and transition state stabilization.
In the Central nervous system, the enzyme contributes to the pool of neurotransmitter glutamate released at excitatory synapses studied in preparations from Hippocampus and Cerebral cortex. In renal proximal tubules, it participates in ammoniagenesis relevant to systemic Acid–base balance investigated in clinics at Mayo Clinic and Cleveland Clinic. In proliferating cells, including Cancer cells and activated Macrophage populations, enhanced activity supports biosynthetic pathways by supplying carbon and nitrogen for nucleotide and amino acid synthesis; these metabolic phenotypes have been characterized in collaborative networks such as The Cancer Genome Atlas.
Dysregulation is linked to oncogenic processes in malignancies including Glioblastoma multiforme, Breast cancer, and Colorectal cancer, where overexpression correlates with aggressive phenotypes reported by research groups at Dana‑Farber Cancer Institute and Memorial Sloan Kettering Cancer Center. In neurological disorders, altered activity has been implicated in models of Epilepsy, Amyotrophic lateral sclerosis, and Alzheimer's disease, with contributions to excitotoxicity and metabolic insufficiency described in studies from National Institute of Neurological Disorders and Stroke. Genetic variants and expression changes have been assessed in patient cohorts assembled by consortia such as European Genome-phenome Archive and clinical trials registries.
Small‑molecule inhibitors targeting the enzyme have been developed, including compounds evaluated in preclinical and clinical studies led by biotechnology companies and academic spinouts affiliated with University of Pennsylvania and University of California, San Diego. Inhibitors modulate tumor growth in xenograft models of Non‑small cell lung carcinoma and Pancreatic cancer, and are being tested in combination with agents targeting mTOR and PD-1 pathways in trials sponsored by collaborations involving National Cancer Institute and pharmaceutical firms. Pharmacodynamic biomarkers include plasma glutamine/glutamate ratios and tumor metabolic imaging used at centers such as Memorial Sloan Kettering Cancer Center.
Category:Mitochondrial enzymes