Related Experiment Videos
A DNA damage response pathway controlled by Tel1 and the Mre11 complex
1Department of Biology, Graduate School of Science, Osaka University, Toyonaka, 560-0043, Osaka, Japan.
Abstract:
We define a DNA damage checkpoint pathway in S. cerevisiae governed by the ATM homolog Tel1 and the Mre11 complex. In mitotic cells, the Tel1-Mre11 complex pathway triggers Rad53 activation and its interaction with Rad9, whereas in meiosis it acts via Rad9 and the Rad53 paralog Mre4/Mek1. Activation of the Tel1-Mre11 complex pathway checkpoint functions appears to depend upon the Mre11 complex as a damage sensor and, at least in meiotic cells, to depend on unprocessed DNA double-strand breaks (DSBs). The DSB repair functions of the Mre11 complex are enhanced by the pathway, suggesting that the complex both initiates and is regulated by the Tel1-dependent DSB signal. These findings demonstrate that the diverse functions of the Mre11 complex in the cellular DNA damage response are conserved in mammals and yeast.
Insights
This study identifies a DNA damage checkpoint pathway in yeast involving Tel1 and the Mre11 complex. This pathway regulates DNA double-strand break repair and is conserved across species.
Area of Science:
- Molecular Biology
- Genetics
- Cell Biology
Background:
- DNA damage checkpoints are crucial for maintaining genomic stability.
- The Mre11 complex and Tel1 kinase play significant roles in DNA damage response.
- Understanding these pathways is essential for comprehending cellular responses to genotoxic stress.
Purpose of the Study:
- To define the DNA damage checkpoint pathway in S. cerevisiae governed by Tel1 and the Mre11 complex.
- To elucidate the roles of this pathway in both mitotic and meiotic cells.
- To investigate the interplay between DNA double-strand break (DSB) sensing and repair.
Main Methods:
- Investigated DNA damage checkpoint activation in S. cerevisiae.
- Utilized genetic analysis to study the roles of Tel1 and the Mre11 complex.
- Examined protein interactions and pathway activation in mitotic and meiotic cells.
Main Results:
- Defined a pathway involving Tel1 and the Mre11 complex that governs DNA damage checkpoints.
- Demonstrated differential activation in mitotic (Rad53/Rad9) versus meiotic (Rad9/Mre4/Mek1) cells.
- Showed Mre11 complex acts as a damage sensor, particularly for unprocessed DSBs in meiosis.
- Found pathway enhances Mre11 complex DSB repair functions, indicating a feedback loop.
Conclusions:
- The Tel1-Mre11 complex pathway is a key regulator of DNA damage response in yeast.
- The Mre11 complex functions both as a sensor and is regulated by the DSB signal.
- The fundamental mechanisms of the Mre11 complex in DNA damage response are conserved between yeast and mammals.