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bioRxiv · 10.1101/2021.06.28.450228

Heat stress reveals the existence of a specialized variant of the pachytene checkpoint in meiosis of Arabidopsis thaliana

de Jager-Braet, J.·Krause, L.·Buchholz, A.·Schnittger, A.
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Abstract

Plant growth and fertility strongly depend on environmental conditions such as temperature. Remarkably, temperature also influences meiotic recombination and thus, the current climate change will affect the genetic make-up of plants. To further understand temperature effects on meiosis, we have followed male meiocytes of Arabidopsis thaliana by live cell imaging under three different temperature regimes, at 21{degrees}C and at heat shock conditions of 30{degrees}C and 34{degrees}C as well as after an acclimatization phase of one week at 30{degrees}C. This work led to a cytological framework of meiotic progression at elevated temperature. We found that an increase to 30{degrees}C, sped up meiotic progression with specific phases being more amenable to heat than others. An acclimatization phase often moderated this effect. A sudden increase to 34{degrees}C promoted a faster progression of meiosis in early prophase compared to 21{degrees}C. However, the phase in which cross-overs maturate was found to be prolonged at 34{degrees}C. Interestingly, mutants involved in the recombination pathway did not show the extension of this phase at 34{degrees}C demonstrating that the delay is recombination dependent. Further analysis revealed the involvement of the ATM kinase in this prolongation indicating the existence of a specialized variant of the pachytene checkpoint in plants.

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de Jager-Braet, J., Krause, L., Buchholz, A., Schnittger, A.. 2021-06-30. Heat stress reveals the existence of a specialized variant of the pachytene checkpoint in meiosis of Arabidopsis thaliana. https://doi.org/10.1101/2021.06.28.450228

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