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A Phenotyping Regimen for Genetically Modified Mice Used to Study Genes Implicated in Human Diseases of Aging
Published on: July 14, 2016
Tyrosine aminotransferase gene regulation during aging
G Servillo1, M A Della Fazia, M Viola-Magni
1Istituto di Patologia Generale, Universitá degli Studi di Perugia, Policlinico Monteluce, 1-06100 Perugia, Italy.
Archives of Gerontology and Geriatrics
|January 1, 1992
Summary
Tyrosine aminotransferase (TAT) enzyme activity and gene expression exhibit a daily rhythm in aging rats. This circadian rhythm shifts with age, particularly in transcript levels, offering insights into gene expression changes in aging animals.
Area of Science:
- Biochemistry
- Molecular Biology
- Gerontology
Background:
- Tyrosine aminotransferase (TAT) is a key enzyme in amino acid metabolism.
- Circadian rhythms regulate numerous physiological processes, including gene expression.
- Aging is associated with significant alterations in metabolic and molecular functions.
Purpose of the Study:
- To investigate the age-related changes in tyrosine aminotransferase (TAT) activity and its gene expression.
- To determine the presence and characteristics of circadian rhythms in TAT activity and transcription across different age groups in rats.
Main Methods:
- Measurement of TAT enzyme activity in rat liver tissue.
- Quantification of TAT specific mRNA levels using molecular techniques.
- Comparative analysis across three age groups: 3, 12, and 24 months.
Main Results:
- Circadian rhythm in TAT activity was observed at all ages, peaking at midnight.
- Age-related differences in the circadian rhythm were noted, with a more pronounced shift in transcript levels.
- Specific mRNA levels and enzyme activity analyses revealed complex modifications in gene expression during aging.
Conclusions:
- The circadian rhythm of TAT is maintained throughout aging but exhibits age-dependent alterations.
- Changes in TAT gene expression, particularly transcript levels, are key to understanding age-related metabolic modifications.
- Combined analysis of enzyme activity and mRNA provides a comprehensive view of aging-related gene expression dynamics.
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