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Updated: Feb 5, 2026
Overexpressing Long Noncoding RNAs Using Gene-activating CRISPR
Published on: March 1, 2019
Overexpression of the
Fabienne E Bayer1, Mirjam Zimmermann1, Anette Preiss1
1Universität Hohenheim, Institut für Genetik, Garbenstr. 30, 70599 Stuttgart, Germany.
Background:
DNA damage generally results in the activation of ATM/ATR kinases and the downstream checkpoint kinases Chk1/Chk2. In Drosophila melanogaster, the ATR homologue meiotic 41 (mei-41) is pivotal to DNA damage repair and cell cycle checkpoint signalling. Although various mei-41 mutant alleles have been analyzed in the past, no gain-of-function allele is yet available. To fill this gap, we have generated transgenic flies allowing temporal and tissue-specific induction of mei-41.
Results:
Overexpression of mei-41 in wing and eye anlagen affects proliferation and a G2/M checkpoint even in the absence of genomic stress. Similar consequences were observed following the overexpression of the downstream kinase Grapes (Grp) but not of Loki (Lok), encoding the respective Drosophila Chk1 and Chk2 homologues, in agreement with their previously reported activities. Moreover, we show that irradiation induced cell cycle arrest was prolonged in the presence of ectopic mei-41 expression. Similar to irradiation stress, mei-41 triggered the occurrence of a slower migrating form of Grp, implying specific phosphorylation of Grp in response to either signal. Using a p53R-GFP biosensor, we further show that overexpression of mei-41 was sufficient to elicit a robust p53 activation in vivo.
Conclusion:
We conclude that overexpression of the Drosophila ATR homologue mei-41 elicits an effectual DNA damage response irrespective of irradiation.
Insights
Overexpressing the Drosophila ATR homologue, mei-41, triggers a DNA damage response and activates p53, even without DNA damage. This study introduces a gain-of-function allele for mei-41 research.
Area of Science:
- Cellular signaling pathways
- DNA damage response mechanisms
- Drosophila melanogaster genetics
Background:
- DNA damage activates ATM/ATR kinases and Chk1/Chk2 checkpoint kinases.
- The Drosophila ATR homologue, mei-41, is crucial for DNA repair and cell cycle checkpoints.
- No gain-of-function mei-41 alleles were previously available.
Purpose of the Study:
- To generate and analyze a gain-of-function allele of mei-41 in Drosophila.
- To investigate the effects of mei-41 overexpression on cell proliferation and checkpoints.
- To explore the role of mei-41 in activating downstream signaling pathways.
Main Methods:
- Generated transgenic Drosophila for temporal and tissue-specific induction of mei-41.
- Analyzed proliferation and G2/M checkpoint in wing and eye anlagen.
- Utilized a p53R-GFP biosensor to assess p53 activation in vivo.
Main Results:
- Overexpression of mei-41 disrupted proliferation and G2/M checkpoints without genomic stress.
- Ectopic mei-41 prolonged irradiation-induced cell cycle arrest.
- mei-41 triggered Grapes (Grp) phosphorylation and robust p53 activation in vivo.
Conclusions:
- Overexpression of Drosophila ATR homologue mei-41 induces a DNA damage response independently of irradiation.
- The gain-of-function mei-41 allele provides a novel tool for studying DNA damage response pathways.
- mei-41 activation is sufficient to elicit a p53-mediated response in vivo.
