Activation of in situ tissue transglutaminase by intracellular reactive oxygen species.
We have investigated the novel function of intracellular reactive oxygen species (ROS) in the activation of in situ tissue transglutaminase (tTGase) by lysophosphatidic acid (LPA) and transforming growth factor-beta (TGF-beta) in Swiss 3T3 fibroblasts. LPA induced a transient increase of intracellular ROS with a maximal increase at 10 min, which was blocked by ROS scavengers, N-acetyl-L-cysteine and catalase. LPA activated tTGase with a maximal increase at 1h, which was inhibited by cystamine and ROS scavengers. Incubation with exogenous H(2)O(2) activated tTGase. TGF-beta also activated tTGase with a maximal activation at 2h and the tTGase activation was inhibited by the ROS scavengers. Scrape-loading of C3 transferase inhibited the ROS production and in situ tTGase activation by LPA and TGF-beta, and the inhibitory effect of C3 transferase was reversed by exogenous H(2)O(2). Microinjection of GTPgammaS inhibited transamidating activity of tTGase stimulated by LPA, TGF-beta, and maitotoxin. These results suggested that intracellular ROS was essential for the activation of in situ tTGase in response to LPA and TGF-beta.
Lee
Zee-Won
ZW
Cell Research Team, Korea Basic Science Institute, Taejon 305-333, Republic of Korea.
Kwon
Sang-Mo
SM
Kim
Sung-Woo
SW
Yi
Sun-Ju
SJ
Kim
Young-Myeong
YM
Ha
Kwon-Soo
KS
D036002:ADP Ribose Transferases / Q000494:pharmacology; D000818:Animals; D001905:Botulinum Toxins / Q000494:pharmacology; D002460:Cell Line; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005347:Fibroblasts / Q000187:drug effects / Q000201:enzymology; D019204:GTP-Binding Proteins / Q000378:metabolism*; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000008:administration & dosage / Q000494:pharmacology; D007700:Kinetics; D008246:Lysophospholipids / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D051379:Mice; D008845:Microinjections; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D017382:Reactive Oxygen Species / Q000378:metabolism*; D016212:Transforming Growth Factor beta / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D011503:Transglutaminases / Q000378:metabolism*
D004791:Enzyme Inhibitors; D008246:Lysophospholipids; D017382:Reactive Oxygen Species; D016212:Transforming Growth Factor beta; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases; D036002:ADP Ribose Transferases; C063007:exoenzyme C3, Clostridium botulinum; D001905:Botulinum Toxins; D019204:GTP-Binding Proteins