| First Author | Plaschkes I | Year | 2005 |
| Journal | J Comp Neurol | Volume | 493 |
| Issue | 3 | Pages | 357-69 |
| PubMed ID | 16261531 | Mgi Jnum | J:104607 |
| Mgi Id | MGI:3612364 | Doi | 10.1002/cne.20793 |
| Citation | Plaschkes I, et al. (2005) DNA topoisomerase I in the mouse central nervous system: Age and sex dependence. J Comp Neurol 493(3):357-69 |
| abstractText | Topoisomerase I (topo I) is a nuclear enzyme responsible for the topological state of DNA and therefore participates in most DNA transactions, particularly in transcription. Topo I, a ubiquitous enzyme, was identified and characterized in various cell types and tissues; however, the characterization of topo I in the intact central nervous system was not performed. Here we investigated, for the first time, the activity, level, and distribution pattern of topo I in the various selected brain regions in the mouse. In the visual cortex, cerebellum, and striatum the activity of topo I was 3-4-fold higher compared to that found in the hippocampus and hypothalamus. Immunohistochemical and immunofluorescence analyses revealed specific distribution patterns of topo I protein in neurons of each of the areas examined. The highest topo I levels were observed in inhibitory neurons. In addition to the expected nuclear localization of this protein, some neurons exhibited significant cytoplasmic content as well. The activity and level of topo I is age- and gender-dependent. It increases from birth to maturity and decreases, more significantly in males, with senescence. These results point to a possible importance and involvement of topo I activity and regulation in various brain functions. |
