Regulation of glutaminase activity and differentiation of the isozyme during development

Katunuma, Nobuhiko; Katsunuma, Tsunehiko; Tomino, Ikuko; Matsuda, Yoshiko

doi:10.1016/0065-2571(68)90015-0

Cited by 36 publications

(3 citation statements)

References 6 publications

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“…Renal glutamine, the substrate for renal ammoniagenesis, is present at only 55% of adult levels at P9 (9). Phosphate-dependent glutaminase, the rate-limiting enzyme for proximal tubule ammonia production, exhibits decreased expression in early fetal development, followed by gradual increases in expression over the initial few weeks following birth (22,23,34,46). Similar findings have been observed for phosphoenolpyruvate carboxykinase (21,60).…”

Section: Discussionsupporting

confidence: 68%

Expression of ammonia transporter family members, Rh B glycoprotein and Rh C glycoprotein, in the developing rat kidney

Han

Lee

Kim

et al. 2010

American Journal of Physiology-Renal Physiology

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Ammonia metabolism is a primary component of acid-base homeostasis but is incompletely developed at time of birth. Rh B glycoprotein (Rhbg) and Rh C glycoprotein (Rhcg) are recently recognized ammonia transporter family members expressed in the mammalian kidney. This study's purpose was to establish the expression and localization of Rhbg and Rhcg during kidney development. We examined kidneys from fetal days 16 (E16), 18 (E18), and 20 (E20), and from the first 21 days of postnatal development. Rhbg was expressed initially at E18, with expression only in the connecting tubule (CNT); at E20, Rhbg was expressed in both the CNT and the medullary collecting duct (MCD). In contrast, Rhcg was first expressed at E16 with basal expression in the ureteric bud; at E18, it was expressed in a subset of CNT cells with an apical pattern, followed by apical and basolateral expression in the MCD at E20. In the cortex, Rhbg and Rhcg expression increased in the CNT before expression in the cortical collecting duct during fetal development. In the MCD, both Rhbg and Rhcg expression was initially in cells in the papillary tip, with gradual removal from the tip during the late fetal period and transition during the early neonatal period to an adult pattern with predominant expression in the outer MCD and only rare expression in cells in the initial inner MCD. Double-labeling with intercalated cell-specific markers identified that Rhbg and Rhcg were expressed initially in CNT cells, CNT A-type intercalated cells and non-A, non-B intercalated cells, and in MCD A-type intercalated cells. We conclude that expression of Rhbg and Rhcg parallels intercalated cell development and that immature Rhbg and Rhcg expression at birth contributes to incomplete ammonia excretion capacity.

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Section: Discussionsupporting

confidence: 68%

Expression of ammonia transporter family members, Rh B glycoprotein and Rh C glycoprotein, in the developing rat kidney

Han

Lee

Kim

et al. 2010

American Journal of Physiology-Renal Physiology

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“…al. (39), and have found that its catalytic properties are indeed identical to those of the -y-glutamyl transpeptidase preparation used here and in previous work in this laboratory (1).…”

Section: Discussionmentioning

confidence: 74%

Stimulation of the Hydrolytic Activity and Decrease of the Transpeptidase Activity of γ-Glutamyl Transpeptidase by Maleate; Identity of a Rat Kidney Maleate-Stimulated Glutaminase and γ-Glutamyl Transpeptidase

Tate

Meister

1974

Proc. Natl. Acad. Sci. U.S.A.

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ABSTRACT-y-Glutamyl transpeptidase catalyzes transfer of the y-glutamyl moiety of glutathione (and other y-glutamyl compounds) to amino acid and peptide acceptors; this reaction probably involves (a) formation of a y-glutamyl enzyme and (b) reaction of the y-glutamyl-enzyme with an acceptor. Maleate decreases the latter reaction and markedly increases hydrolysis of the y-glutamyl donor, apparently by affecting the enzyme so as to facilitate reaction of the y-glutamyl enzyme with water. Transpeptidase catalyzes y-glutamyl hydroxamate formation from many y-glutamyl compounds and hydroxylamine; this reaction is stimulated 4-to 5-fold by maleate. Glutamine, a poor substrate for transpeptidation as compared to glutathione, is slowly hydrolyzed and converted to y-glutamyl-glutamine by the transpeptidase; in the presence of maleate, hydrolysis of glutamine is markedly (>10-fold) increased, as is also its conversion to -y-glutamyl hydroxamate in the presence of hydroxylamine. The findings suggest that the previously described "maleate-stimulated phosphate-independent glutaminase" is a catalytic function of -y-glutamyl transpeptidase. Transpeptidase-catalyzed glutaminase activity may play a role in renal ammoniagenesis. The ability of maleate to decrease transpeptidation of y-glutamyl compounds (and to increase their hydrolysis to glutamate), when considered in the light of earlier findings that treatment of animals with maleate produces aminoaciduria, is consistent with function of transpeptidase and the y-glutamyl cycle in amino-acid transport.

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“…As mentioned above, it is possible that p-MB and NEM inhibit glutaminase other than PAG in intact synaptosomes. Enzymes that might be affected are soluble ADP-sensitive glutaminase (Goldstein et al, 1957), and microsomal MAG (Katunuma et al, 1968) which is generally believed to be identical with y-GT (Curthoys et al, 1975;Tate and Meister, 1975). However, no soluble ADP-sensitive glutaminase has been found and the high-speed supernatant following the precipitation of microsomes contains no detectable glutaminase activity.…”

Section: E Kvamme a N D B E Olsenmentioning

confidence: 99%

Evidence for Compartmentation of Synaptosomal Phosphate‐Activated Glutaminase

Kvamme

Olsen

1981

Journal of Neurochemistry

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Phosphate-activated glutaminase (EC 3.5.1.2) in synaptosomal preparations is inhibited 40-60% by the sulphydryl group reagent N-ethylmaleimide (NEM), forming the basis for distinction between NEM-sensitive and NEM-insensitive glutaminases. The NEM effect cannot be explained by differential effects on distinct glutaminases because other glutaminases have not been detected, and the synaptosomal glutaminase activity can be fully accounted for by the activity of phosphate-activated glutaminase. By fractionation of mitochondria isolated from synaptosomal preparations, which are preincubated with and without NEM, both NEM-sensitive and NEM-insensitive glutaminases are found to be localized to the inner mitochondrial membrane. Variations in pH (7.0-7.6) and the phosphate concentration (5-10 mM) affect chiefly NEM-sensitive glutaminase, demonstrating that this glutaminase may be subject to regulation by compounds in the cytosol having restricted permeability to the inner mitochondrial membrane. Since p-hydroxymercuribenzoate, which is known to be impermeable to the inner mitochondrial membrane, inhibits glutaminase similarly to NEM, phosphate-activated glutaminase is assumed to be compartmentalized within the inner mitochondrial membrane. Thus, NEM-sensitive glutaminase is localized to the outer face and NEM-insensitive glutaminase to the inner region of this membrane and probably also to the matrix region.

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Regulation of glutaminase activity and differentiation of the isozyme during development

Cited by 36 publications

References 6 publications

Expression of ammonia transporter family members, Rh B glycoprotein and Rh C glycoprotein, in the developing rat kidney

Expression of ammonia transporter family members, Rh B glycoprotein and Rh C glycoprotein, in the developing rat kidney

Stimulation of the Hydrolytic Activity and Decrease of the Transpeptidase Activity of γ-Glutamyl Transpeptidase by Maleate; Identity of a Rat Kidney Maleate-Stimulated Glutaminase and γ-Glutamyl Transpeptidase

Evidence for Compartmentation of Synaptosomal Phosphate‐Activated Glutaminase

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