Biogenesis of peroxisomes: sequential biosynthesis of the membrane and matrix proteins in the course of hepatic regeneration.
Biogenesis of peroxisomes: sequential biosynthesis of the membrane and matrix proteins in the course of hepatic regeneration.
复制标题
过氧化物酶体的生物发生：肝再生过程中膜和基质蛋白的连续生物合成。
DOI：
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发表时间：
1990
影响因子：
6.6
通讯作者：
A. Völkl
中科院分区：
文献类型：
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作者：
G. Lüers;K. Beier;T. Hashimoto;H. Fahimi;A. Völkl
采用差速离心结合免疫印迹、活体脉冲标记和免疫电镜技术，在大鼠部分肝切除（PH）后再生肝模型中研究了过氧化物酶体的生物发生。过氧化氢酶的总活性急剧下降后，PH，逐渐恢复到正常水平，在几天内。在16至32小时期间的酶活性开始增加，首先在重线粒体部分，在28小时转移到粗过氧化物酶体，并在32小时的微粒体部分，这表明从头形成过氧化物酶体的出芽或碎片从较大的聚集体。而大多数过氧化物酶体基质蛋白在PH后16至32小时内减少，26和70 kDa的过氧化物酶体膜蛋白增加。此外，在体内脉冲标记的放射性亮氨酸的研究表明，在过氧化物酶体膜的比活性显着更高的水平比在基质亚组分在16小时，增加标记的基质在PH后32小时。这些研究结果表明，从头形成过氧化物酶体在再生大鼠肝脏是由膜蛋白的合成，其次是由基质成分。
The biogenesis of peroxisomes was investigated in the model of regenerating rat liver after partial hepatectomy (PH), using analytical differential centrifugation in combination with immunoblotting and in vivo pulse labeling as well as immunoelectron microscopy. The total activity of catalase decreased sharply after PH, returning gradually over several days to normal levels. In the 16 to 32-h period the enzyme activity started to increase first in the heavy mitochondrial fraction, shifting at 28 h to the crude peroxisomal and at 32 h to the microsomal fraction, suggesting de novo formation of peroxisomes by budding or fragmentation from larger aggregates. Whereas most peroxisomal matrix proteins were reduced during the 16 to 32-h period after PH, the 26 and 70 kDa peroxisomal membrane proteins were increased. Moreover, in vivo pulse labeling studies with radioactive leucine showed significantly higher levels of specific activity in the peroxisomal membrane than in the matrix subfractions at 16 h with increasing labeling of the matrix at 32 h after PH. These findings suggest that de novo formation of peroxisomes in regenerating rat liver is initiated by the synthesis of membrane proteins and is followed by that of the matrix components.