Regulation of NAD+ glycohydrolase activity by NAD(+)-dependent auto-ADP-ribosylation.
NAD+ glycohydrolase (NADase; EC 3.2.2.5) is an enzyme that catalyses hydrolysis of NAD+ to produce ADP-ribose and nicotinamide. Its physiological role and the regulation of its enzymic activity have not been fully elucidated. In the present study, the mechanism of self-inactivation of NADase by its substrate, NAD+, was investigated by using intact rabbit erythrocytes and purified NADase. Our results suggest that inactivation of NADase was due an auto-ADP-ribosylation reaction. ADP-ribosylated NADase of rabbit erythrocytes was deADP-ribosylated when incubated without NAD+, and thus enzyme activity was simultaneously restored. These findings suggest that reversible auto-ADP-ribosylation of NADase might regulate the enzyme's activity in vivo.
Han
M K
MK
Department of Biochemistry, Chonbuk National University Medical School, Chonju, Korea.
Lee
J Y
JY
Cho
Y S
YS
Song
Y M
YM
An
N H
NH
Kim
H R
HR
Kim
U H
UH
D000246:Adenosine Diphosphate Ribose / Q000378:metabolism*; D000818:Animals; D001665:Binding Sites; D003545:Cysteine / Q000737:chemistry; D004912:Erythrocytes / Q000201:enzymology; D066298:In Vitro Techniques; D007700:Kinetics; D008970:Molecular Weight; D009243:NAD / Q000378:metabolism*; D009244:NAD+ Nucleosidase / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D011817:Rabbits
D009243:NAD; D000246:Adenosine Diphosphate Ribose; D009244:NAD+ Nucleosidase; D003545:Cysteine