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Summary Plant responses to abiotic environmental challenges are known to have lasting effects on the plant beyond the initial stress exposure. Some of these lasting effects are transgenerational, affecting the next generation. The plant response to elevated carbon dioxide (CO2) levels has been well studied. However, these investigations are typically limited to plants grown for a single generation in a high CO2environment while transgenerational studies are rare.We aimed to determine transgenerational growth responses in plants after exposure to high CO2by investigating the direct progeny when returned to baseline CO2levels.We found that both the flowering plantArabidopsis thalianaand seedless nonvascular plantPhyscomitrium patenscontinue to display accelerated growth rates in the progeny of plants exposed to high CO2. We used the model species Arabidopsis to dissect the molecular mechanism and found that DNA methylation pathways are necessary for heritability of this growth response.More specifically, the pathway of RNA‐directed DNA methylation is required to initiate methylation and the proteins CMT2 and CMT3 are needed for the transgenerational propagation of this DNA methylation to the progeny plants. Together, these two DNA methylation pathways establish and then maintain a cellular memory to high CO2exposure.
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Physcomitrium patens response to elevated CO 2 is flexible and determined by an interaction between sugar and nitrogen availability
Summary Mosses hold a unique position in plant evolution and are crucial for protecting natural, long‐term carbon storage systems such as permafrost and bogs. Due to small stature, mosses grow close to the soil surface and are exposed to high levels of CO2, produced by soil respiration. However, the impact of elevated CO2(eCO2) levels on mosses remains underexplored.We determined the growth responses of the mossPhyscomitrium patensto eCO2in combination with different nitrogen levels and characterized the underlying physiological and metabolic changes.Three distinct growth characteristics, an early transition to caulonema, the development of longer, highly pigmented rhizoids, and increased biomass, define the phenotypic responses ofP. patensto eCO2. Elevated CO2impacts growth by enhancing the level of a sugar signaling metabolite, T6P. The quantity and form of nitrogen source influences these metabolic and phenotypic changes. Under eCO2,P. patensexhibits a diffused growth pattern in the presence of nitrate, but ammonium supplementation results in dense growth with tall gametophores, demonstrating high phenotypic plasticity under different environments.These results provide a framework for comparing the eCO2responses ofP. patenswith other plant groups and provide crucial insights into moss growth that may benefit climate change models.
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- PAR ID:
- 10472874
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 241
- Issue:
- 3
- ISSN:
- 0028-646X
- Format(s):
- Medium: X Size: p. 1222-1235
- Size(s):
- p. 1222-1235
- Sponsoring Org:
- National Science Foundation
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