DNA Synthesis and Nucleoside Metabolism in Human Tonsillar Lymphocyte Subpopulations
| Autor: | Maria Staub, M. Benczur, Tatjana Spasokukotskaja, Ferenc A. Antoni |
|---|---|
| Rok vydání: | 1988 |
| Předmět: |
DNA polymerase
Palatine Tonsil Cell Population DNA-Directed DNA Polymerase Deoxycytidine Thymidine Kinase chemistry.chemical_compound Deoxycytidine Kinase medicine Humans Nucleotide Lymphocytes Child education chemistry.chemical_classification education.field_of_study biology DNA synthesis Nucleosides DNA General Medicine Antigens Differentiation Molecular biology Dithiothreitol medicine.anatomical_structure Otorhinolaryngology chemistry Biochemistry Child Preschool biology.protein Thymidine |
| Zdroj: | Acta Oto-Laryngologica. 105:118-124 |
| ISSN: | 1651-2251 0001-6489 |
| Popis: | High (HD) and low (LD) density cells were separated on 25% BSA gradient from tonsils of 3-6 years old children. Early B lymphocyte markers and sIg-s were found on the surface of 59-82% of the LD cells. This cell population was 5-6 times more active in DNA synthesis (3H-thymidine incorporation, DNA polymerase activity) than the HD cells. The total uptake of 3H-deoxycytidine was about the same as that of 3H-thymidine. As long as practically all thymidine taken up by the cells was immediately incorporated into DNA (90-95%), only 10-15% of deoxycytidine was incorporated into DNA under the same conditions, indicating different pool sizes for the DNA precursors. The majority of deoxycytidine (70%) was converted and incorporated as dTMP. A considerable part of labeled deoxycytidine could be detected in the soluble pool in form of nucleotides (3-8%), and in an unknown form, called substance X (8-14%). Substance X was purified by TL chromatography and identified by HPLC as deoxycytidine containing liponucleotides, probable precursors for plasmamembranes. The preferential utilisation of deoxycytidine for DNA and membrane synthesis in immature B lymphocytes draws the attention to its function in early events of lymphocyte maturation. |
| Databáze: | OpenAIRE |
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