Expression of human mitochondrial NADP-dependent isocitrate dehydrogenase during lymphocyte activation.
In the process of identifying genes involved in optimization of lymphocyte activation, we have cloned the human mitochondrial NADP-dependent isocitrate dehydrogenase (mNADP-IDH) cDNA. The cDNA and its deduced amino acid (AA) sequence had a high degree of homology with those of the porcine and bovine. The heart and muscle had the highest constitutive expression of the gene. The expression of steady-state mRNA in the resting T and B lymphocytes was low but was induced after mitogen stimulation. The mRNA levels peaked around 48 h and remained elevated at 72 h. At the protein level, the mitochondrial but not cytosolic NADP-IDH activity was augmented after the mitogen stimulation. There was no cell cycle-dependent fluctuation of mNADP-IDH expression in synchronized Jurkat cells. In T and B cells, rapamycin (RAPA) could repress the mitogen-stimulated mNADP-IDH expression, although most of the early or late phase activation-related genes including a G-protein beta subunit-related gene H12.3 were not affected by the drug. The restricted expression of the gene in certain tissues and the activation-related expression in lymphocytes suggest that this gene might be necessary for optimal functions in heart, muscle, and the activated lymphocytes.
Luo
H
H
Laboratory of Nephrology and Transplantation Immunology, Notre-Dame Hospital Research Center, Montreal, Quebec, Canada.
Shan
X
X
Wu
J
J
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D002453:Cell Cycle / Q000502:physiology; D002460:Cell Line; D003001:Cloning, Molecular; D016193:G1 Phase / Q000502:physiology; D006801:Humans; D007521:Isocitrate Dehydrogenase / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics; D008213:Lymphocyte Activation; D008222:Lymphokines / Q000494:pharmacology; D008928:Mitochondria / Q000201:enzymology*; D008969:Molecular Sequence Data; D011090:Polyenes / Q000494:pharmacology; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D020123:Sirolimus; D013552:Swine
D008222:Lymphokines; D011090:Polyenes; D007521:Isocitrate Dehydrogenase; D020123:Sirolimus