Differences in the half‐lives of some mitochondrial rat liver enzymes may derive partially from hepatocyte heterogeneity

FEBS Letters

Knecht, Erwin¹  Vargas, Jose Luis¹  Roche, Enrique¹  Grisolía, Santiago¹ 

[1] Instituto de Investigaciones Citológicas de la Caja de Ahorros de Valencia, Amadeo de Saboya, 4, 46010 Valencia, Spain

关键词: Carbamoyl-phosphate synthase;    Glutamate dehydrogenase;    Ornithine carbamoyltransferase;    Hepatocyte heterogeneity;    Protein degradation;    AAT;    alanine aminotransferase;    BSA;    bovine serum albumin;    CPS;    carbamoyl phosphate synthase;    GDH;    glutamate dehydrogenase;    LDH;    lactic dehydrogenase;    PK;    pyruvate kinase;    OTC;    ornithine carbamoyl transferase;    t ½;    half-life;   

DOI  :  10.1016/0014-5793(87)80444-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The different turnover rates of rat liver mitochondrial enzymes make autophagy unlikely to be the main mechanism for degradation of mitochondria. Although alternatives have been presented, hepatocyte heterogeneity has not been considered. Lighter hepatocytes isolated in a discontinuous Percoll gradient contain more glutamate dehydrogenase (GDH) (half-life 1 day) and a more active autophagic system than heavier hepatocytes. The latter contain more carbamoyl phosphate synthase (CPS) and ornithine carbamoyl transferase (OTC) (half-lives 8 days) but less lysosomal activity. As expected, isolated autophagic vacuoles contain, relative to the mitochondrial content, 3-times less OTC and CPS than GDH, probably reflecting a faster lysosomal engulfment of mitochondria in the light hepatocytes (which contain more GDH). These data may explain some of the half-life differences of the enzymes studied.

【 授权许可】

Unknown