Q57906944
Dotaz
Zobrazit nápovědu
This study is a thorough examination of the effects of the DNA polymerase inhibitor aphidicolin on the nuclear cycle and cell cycle progression characteristics, as well as their reversibility, in Giardia intestinalis. Giardia trophozoites are arrested in the G1/S-junction after aphidicolin treatment according to their DNA content. However, cell growth continues and trophozoites arrested with aphidicolin resemble cells in the G2 phase and trophozoites in ageing cultures. Extensive treatment with aphidicolin causes side effects and we detected positive signals for phosphorylated histone H2A, which, in mammalian cells, is involved in a signalling pathway triggered as a reaction to double stranded DNA breaks. These results suggest that aphidicolin causes dissociation of the nuclear and cytoplasmic cycles, a phenomenon that has also been described for other inhibitors in mammalian cell lines. Thus, if aphidicolin is used for synchronization of Giardia trophozoites, this fact must be accounted for, and treatment with aphidicolin must be minimal. Copyright 2009 Elsevier Inc. All rights reserved.
- MeSH
- afidikolin farmakologie MeSH
- bromodeoxyuridin metabolismus MeSH
- buněčný cyklus účinky léků MeSH
- časové faktory MeSH
- cyklin B analýza MeSH
- DNA-dependentní DNA-polymerasy MeSH
- fluorescenční protilátková technika MeSH
- fosforylace účinky léků MeSH
- Giardia lamblia cytologie genetika účinky léků MeSH
- histony metabolismus MeSH
- inhibitory enzymů farmakologie MeSH
- inhibitory syntézy nukleových kyselin MeSH
- mitotický index MeSH
- poškození DNA účinky léků MeSH
- protozoální DNA biosyntéza účinky léků MeSH
- průtoková cytometrie MeSH
- replikace DNA účinky léků MeSH
- trofozoiti cytologie účinky léků MeSH
- Publikační typ
- práce podpořená grantem MeSH
BACKGROUND: Slow-fast analysis is a simple and effective method to reduce the influence of substitution saturation, one of the causes of phylogenetic noise and long branch attraction (LBA) artifacts. In several steps of increasing stringency, the slow-fast analysis omits the fastest substituting alignment positions from the analysed dataset and thus increases its signal/noise ratio. RESULTS: Our program SlowFaster automates the process of assessing the substitution rate of the alignment positions and the process of producing new alignments by deleting the saturated positions. Its use is very simple. It goes through the whole process in several steps: data input - necessary choices - production of new alignments. CONCLUSION: SlowFaster is a user-friendly tool providing new alignments prepared with slow-fast analysis. These data can be used for further phylogenetic analyses with lower risk of long branch attraction artifacts.
