PRESENCE OF ORNITHINE DECARBOXYLASE ANTIZYME IN PRIMARY CULTURED-HEPATOCYTES OF THE FROG XENOPUS-LAEVIS

被引:6
作者
BABY, TG [1 ]
HAYASHI, S [1 ]
机构
[1] JIKEI UNIV,DEPT NUTR,MINATO KU,TOKYO 105,JAPAN
关键词
ORNITHINE DECARBOXYLASE ANTIZYME; HEPATOCYTE; PUTRESCINE; ORNITHINE DECARBOXYLASE; (DECAY IN X-LAEVIS);
D O I
10.1016/0167-4889(91)90150-V
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
Ornithine decarboxylase (ODC; EC 4.1.1.17) could be induced in primary cultured hepatocytes of the frog, Xenopus laevis, by a hypotonic treatment. Addition of 10 mM putrescine caused a rapid decay of preinduced ODC after a lag period of 30 min. The putrescine-induced ODC decay was faster than the ODC decay in the presence of cycloheximide. Simultaneous addition of cycloheximide blocked the putrescine-induced acceleration of ODC decay, indicating an involvement of protein synthesis. Addition of putrescine to normal medium caused complete loss of ODC activity in 2 h and then ODC-inhibitory activity appeared and progressively increased. The inhibitory factor was non-dialysable and temperature-sensitive and showed a time-independent and stoichiometric pattern of ODC inhibition. On the basis of these observations the inhibitory factor was identified as ODC antizyme. These results indicated that in frog hepatocytes, like in mammalian cells and tissues, ODC is under negative feedback regulation mediated by antizyme.
引用
收藏
页码:161 / 164
页数:4
相关论文
共 37 条