Arginase-1
Arginase-1 (ARG1) is a cytosolic manganese-independent-of-name hydrolase of the arginase family that catalyses the hydrolysis of arginine to ornithine and urea. Formerly named "arginase, liver", it is the type I arginase, a component of the urea cycle that also shapes arginine availability in immune responses. Browse Assay Genie's current range of Arginase-1 research reagents below, or read on for the biology behind the target.
Arginase-1 catalyses the hydrolysis of arginine to ornithine and urea. In nonhepatic tissues it functions in L-arginine homeostasis, where nitric oxide synthase (NOS) and arginase compete for the available intracellular arginine. Arginine metabolism is a critical regulator of innate and adaptive immune responses, and Arginase-1 sits at the centre of this control.
In polymorphonuclear granulocytes (PMN) the enzyme is part of an antimicrobial effector pathway. When PMN die, Arginase-1 is liberated from the phagolysosome and depletes arginine in the surrounding microenvironment, which suppresses T cell and natural killer (NK) cell proliferation and cytokine secretion. In group 2 innate lymphoid cells (ILC2s) it promotes acute type 2 inflammation in the lung and is involved in optimal ILC2 proliferation, but not survival. In humans, its immunological role in the monocytic, macrophage and dendritic cell lineage remains unsettled.
The ARG1 gene encodes the type I isoform of mammalian arginase. Types I and II differ in tissue distribution, subcellular localisation, immunological cross-reactivity and physiological function; Arginase-1 is cytosolic and expressed predominantly in the liver as a component of the urea cycle, whereas the type II enzyme is encoded by ARG2. Two transcript variants encoding different isoforms have been reported. Inherited deficiency of Arginase-1 causes argininemia, an autosomal recessive disorder characterised by hyperammonemia. The rat ortholog is also named Arg1.
Arginase-1 is a urea cycle component expressed mainly in the liver, making it central to studies of arginine hydrolysis and nitrogen handling.
Release of Arginase-1 from dying PMN depletes local arginine and suppresses T cell and NK cell proliferation and cytokine secretion.
In ILC2s, Arginase-1 promotes acute type 2 lung inflammation and supports optimal proliferation, making it relevant to type 2 immunity.
Inherited Arginase-1 deficiency results in argininemia, an autosomal recessive disorder characterised by hyperammonemia, so the enzyme is studied in this metabolic disease.
Arginase-1 hydrolyses arginine to ornithine and urea. It acts in the urea cycle in the liver and regulates arginine availability elsewhere, competing with nitric oxide synthase for substrate. By depleting arginine it can limit T cell and NK cell proliferation and cytokine secretion.
The HGNC approved name is arginase 1, with the previous name "arginase, liver". It is also called the type I arginase to distinguish it from the type II isoform encoded by ARG2. Two transcript variants encoding different isoforms have been described for the gene.
Yes. Inherited deficiency of Arginase-1 results in argininemia, an autosomal recessive disorder characterised by hyperammonemia. The enzyme is also studied in immunology because arginine depletion affects T cell and NK cell responses. Rat Arg1 is the corresponding rat ortholog; check the datasheet of any product for its validated reactivity.
Other arginase isoforms, nitric oxide synthases and urea cycle enzymes that relate to arginine metabolism, with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P05089; product specifications from Assay Genie datasheets.