| Autor: |
Kurasz K; Silesian University of Technology, Akademicka 16, 44-100 Gliwice, Poland., Rzeszowska-Wolny J; Silesian University of Technology, Akademicka 16, 44-100 Gliwice, Poland., Oliński R; Department of Clinical Biochemistry, Faculty of Pharmacy, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, Karlowicza 24, 85-092 Bydgoszcz, Poland., Foksiński M; Department of Clinical Biochemistry, Faculty of Pharmacy, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, Karlowicza 24, 85-092 Bydgoszcz, Poland., Fujarewicz K; Silesian University of Technology, Akademicka 16, 44-100 Gliwice, Poland. |
| Abstrakt: |
In living cells, some reactions can be conducted by more than one enzyme and sometimes it is difficult to establish which enzyme is responsible. Such is the case with proteins from the TET family, capable of converting 5-methyl-2'-deoxycytidine (5-mdC) in DNA to 5-(hydroxymethyl)-2'-deoxycytidine (5-hmdC) and further to 5-formyl-2'-deoxycytidine (5-fdC) and 5-carboxy-2'-deoxycytidine (5-cadC). The estimation of the efficiency of particular TETs in particular oxidative reactions and different cell types is important but experimentally difficult. Here, we propose an approach with mathematical modeling in which methylation and known deoxycytidine modification pathways are presented by 343 possible model versions with assumed different combinations of TET1, 2, and 3 activities in different pathways. Model parameters were calculated on the basis of 5-mdC, 5-hmdC, 5-fdC, 5-cadC, and 5-hmdU levels experimentally assessed in five human cultured cell lines and previously published. Selection of the model versions that give in simulations the best average fit to experimental data suggested that not all TET proteins participate in all modification reactions and that TET3 activity may be especially important in the reaction of 5-fdC removal. |
