PMID: 4149773Feb 1, 1974

Regulation of tyrosine aminotrasferase activity in two liver-derived permanent cell lines

The Journal of Cell Biology
L Sellers, D Granner


The regulation of tyrosine aminotransferase (TAT) activity has been examined in two liver-derived heteroploid cell lines. One (hepatoma tissue culture cells [HTC]) was derived from a hepatoma, the other (rat liver culture cells [RLC]) was derived from normal liver. The two cell lines show the following striking similarities in the control of this specific protein: (a) The kinetics of TAT induction by dexamethasone phosphate (DxP) are similar in randomly growing cells of both lines; (b) During mitosis and early G(1) phase of the cell cycle TAT activity cannot be induced by DxP in either cell line; (c) 2-3 h into G(1), when both lines become sensitive to inducer, basal enzyme activity declines to a new steady-state level; (d) Preinduced cells collected in mitosis show approximately twice the level of TAT activity as fully induced, randomly growing cultures and this activity is maintained in early G(1) with or without the inducer; and (e) Inhibition of RNA synthesis by 5 microg/ml of actinomycin D in preinduced, synchronized cells allows TAT activity to remain at constitutive levels throughout G(1), even in the absence of inducer. These results are presented in support of a previously described model which states that glucocortico...Continue Reading


Feb 1, 1979·Journal of Cellular Physiology·J M HarmonE B Thompson

Related Concepts

Cell Division Phases
Demecolcine, (+-)-Isomer
Enzyme Induction
Liver Carcinoma
Malignant Neoplasm of Liver
M Phase, Mitotic
Neoplasms, Experimental

Trending Feeds


Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Synthetic Genetic Array Analysis

Synthetic genetic arrays allow the systematic examination of genetic interactions. Here is the latest research focusing on synthetic genetic arrays and their analyses.

Congenital Hyperinsulinism

Congenital hyperinsulinism is caused by genetic mutations resulting in excess insulin secretion from beta cells of the pancreas. Here is the latest research.

Neural Activity: Imaging

Imaging of neural activity in vivo has developed rapidly recently with the advancement of fluorescence microscopy, including new applications using miniaturized microscopes (miniscopes). This feed follows the progress in this growing field.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Epigenetic Memory

Epigenetic memory refers to the heritable genetic changes that are not explained by the DNA sequence. Find the latest research on epigenetic memory here.

Cell Atlas of the Human Eye

Constructing a cell atlas of the human eye will require transcriptomic and histologic analysis over the lifespan. This understanding will aid in the study of development and disease. Find the latest research pertaining to the Cell Atlas of the Human Eye here.

Femoral Neoplasms

Femoral Neoplasms are bone tumors that arise in the femur. Discover the latest research on femoral neoplasms here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Related Papers

Proceedings of the National Academy of Sciences of the United States of America
D MartinM A Bresler
Proceedings of the National Academy of Sciences of the United States of America
D MartinD Granner
© 2021 Meta ULC. All rights reserved