Cloning of antizyme inhibitor, a highly homologous protein to ornithine decarboxylase.
The degradation of ornithine decarboxylase (ODC) catalyzed by the 26 S proteasome is accelerated by antizyme, an ODC inhibitory protein induced by polyamines. Previously, we have found another possible regulatory protein of ODC degradation, antizyme inhibitor. Antizyme inhibitor binds to the antizyme with a higher affinity than that of ODC, releasing ODC from ODC-antizyme complex. We report here the cDNA sequence of rat heart antizyme inhibitor. The deduced sequence of the protein is highly similar to, but distinct from, sequences of ODCs from various species. Antizyme inhibitor contains amino acid residues required for formation of active sites of ODC, but it completely lacks ODC activity. Antizyme inhibitor has no homology with peptide sequence in the mammalian ODC carboxyl terminus, which is needed for rapid turnover of ODC. It inhibits antizyme-dependent ODC degradation, but, unlike ODC, its degradation is not accelerated by antizyme.
Murakami
Y
Y
Department of Biochemistry 2, The Jikei University School of Medicine, Minato-ku, Tokyo 105, Japan.
Ichiba
T
T
Matsufuji
S
S
Hayashi
S
S
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D003001:Cloning, Molecular; D004791:Enzyme Inhibitors; D015870:Gene Expression; D008322:Mammals; D008969:Molecular Sequence Data; D009206:Myocardium / Q000378:metabolism; D016366:Open Reading Frames; D009955:Ornithine Decarboxylase / Q000737:chemistry*; D065108:Ornithine Decarboxylase Inhibitors; D010447:Peptide Hydrolases / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex; D014176:Protein Biosynthesis; D011506:Proteins / Q000737:chemistry* / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
D004791:Enzyme Inhibitors; D065108:Ornithine Decarboxylase Inhibitors; D011506:Proteins; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; C031017:ornithine decarboxylase antizyme; D010447:Peptide Hydrolases; D046988:Proteasome Endopeptidase Complex; C061553:ATP dependent 26S protease; D009955:Ornithine Decarboxylase