Cloning and characterization of a human polyamine oxidase that is inducible by polyamine analogue exposure.
Mammalian polyamine catabolism is under the control of two enzymes, spermidine/spermine N1-acetyltransferase and the flavin adenine dinucleotide-dependent polyamine oxidase (PAO). In this study, the cloning and initial characterization of human PAO is reported. A 1894-bp cDNA with an open reading frame of 1668-bp codes for a protein of 555 amino acids. In vitro transcription/translation of this cDNA clone produces the expected M(r) 61,900 protein with PAO activity. The PAO activity of this clone is inhibited by MDL 72,527, a specific inhibitor of mammalian PAO. However, neither pargyline, a specific monoamine oxidase inhibitor, nor semicarbazide, a specific diamine oxidase inhibitor, inhibits the PAO activity of this clone. PAO has been referred to as being constitutively expressed. However, 24-h exposure of a non-small cell lung carcinoma cell line, NCI H157, to 10 microM of N1,N"-bis(ethyl)norspermine results in approximately 5-fold induction of PAO mRNA and a >3-fold induction of PAO activity. These results demonstrate that in at least one cell type, PAO is up-regulated in response to polyamine analogue exposure. The PAO clone described here should provide a useful tool, which will facilitate the dissection of the role of polyamine catabolism in normal growth and in response to the antitumor polyamine analogues.
Wang
Y
Y
The Johns Hopkins Oncology Center, Bunting-Blaustein Cancer Research Building, Baltimore, Maryland 21231, USA.
Devereux
W
W
Woster
P M
PM
Stewart
T M
TM
Hacker
A
A
Casero
R A
RA
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D005796:Genes / Q000235:genetics; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D000587:Oxidoreductases Acting on CH-NH Group Donors / Q000235:genetics* / Q000378:metabolism; D011073:Polyamines / Q000737:chemistry / Q000494:pharmacology*; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured; D000097667:Polyamine Oxidase
D018076:DNA, Complementary; D000587:Oxidoreductases Acting on CH-NH Group Donors; D011073:Polyamines; D012333:RNA, Messenger; D000097667:Polyamine Oxidase