A high-quality genome of the mass-blooming desert plant Cistanthe longiscapa and its photosynthetic behavior related to drought and life history

Chomentowska, A.; Raimondeau, P.; Wei, L.; Jose, E. G. D.; Dauerman, S. G.; Davis, V. Z.; Moreira-Munoz, A.; Peralta, I. E.; Edwards, E. J.

doi:10.1101/2024.11.06.622337

bioRxiv · 10.1101/2024.11.06.622337

A high-quality genome of the mass-blooming desert plant Cistanthe longiscapa and its photosynthetic behavior related to drought and life history

Chomentowska, A.·Raimondeau, P.·Wei, L.·Jose, E. G. D.·Dauerman, S. G.·Davis, V. Z.·Moreira-Munoz, A.·Peralta, I. E.·Edwards, E. J.

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Abstract

O_LICrassulacean acid metabolism (CAM) photosynthesis has independently evolved many times in arid-adapted plant lineages. Cistanthe longiscapa (Montiaceae), a desert mass-blooming annual, can upregulate CAM facultatively upon stress such as drought. Few studies, however, consider life history stages when measuring CAM activity or its facultative onset. C_LIO_LITo test the effect of drought and flowering on photosynthetic activity, we assayed Cistanthe individuals in fully-watered and drought conditions, as well as fully-watered individuals at pre-flowering and flowering life stages. We assembled and annotated a chromosome-scale genome of C. longiscapa and compared it with the genome of Portulaca amilis and analyzed differential gene expression. C_LIO_LIResults show significantly upregulated CAM in drought conditions as compared to fully-watered conditions; furthermore, flowering individuals showed slightly higher CAM activity as compared to pre-flowering plants, even when fully-watered. Differential gene expression analyses provide preliminary support for the possible co-regulation of CAM expression and reproduction. C_LIO_LIWe emphasize the potentially missed significance of life history in the CAM literature, and consider how the CAM biochemical module could become co-opted into other plant behaviors and responses, such as the shift to reproduction or flowering in annuals. C_LI

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Chomentowska, A., Raimondeau, P., Wei, L., Jose, E. G. D., Dauerman, S. G., Davis, V. Z., Moreira-Munoz, A., Peralta, I. E., Edwards, E. J.. 2024-11-07. A high-quality genome of the mass-blooming desert plant Cistanthe longiscapa and its photosynthetic behavior related to drought and life history. https://doi.org/10.1101/2024.11.06.622337

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