Water scarcity, resulting from climate change, poses a significant threat to ecosystems. We sequenced the genome of The genome was assembled into 12 chromosomes encompassing 21 169 protein‐coding genes. Comparative analysis revealed copy number and transcript abundance differences in known desiccation‐associated gene families, and highlighted genome‐level variation among species that may reflect adaptation to different habitats. A significant number of abscisic acid (ABA)‐responsive genes were found to be negatively regulated by a MYB transcription factor (MYB55) that was upstream of the The new genomic resources from this emerging model moss offer novel insights into how plants regulate their responses to water deprivation.
With global climate change, water scarcity threatens whole agro/ecosystems. The desert moss
- NSF-PAR ID:
- 10452792
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- The Plant Journal
- Volume:
- 105
- Issue:
- 5
- ISSN:
- 0960-7412
- Page Range / eLocation ID:
- p. 1339-1356
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Summary Syntrichia ruralis , a dryland desiccation‐tolerant moss, provides valuable insights into survival of water‐limited conditions.S. ruralis , conducted transcriptomic analyses, and performed comparative genomic and transcriptomic analyses with existing genomes and transcriptomes, including with the close relativeS. caninervis . We took a genetic approach to characterize the role of anS. ruralis transcription factor, identified in transcriptomic analyses, inArabidopsis thaliana .S. ruralis ortholog of ABA‐insensitive 3 (ABI3). We determined that this conserved MYB transcription factor, uncharacterized inArabidopsis , acts as a negative regulator of an ABA‐dependent stress response inArabidopsis . -
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PREMISE Desiccation tolerance (DT) is a widespread phenomenon among land plants, and variable ecological strategies for DT are likely to exist. Using
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RoDmin (10‒25 min), followed by gemmae (3‒10 h) and protonema (14‒20 h). Adult shoots exhibited no detectable damage 24 h postrehydration following a rapid‐dry only at the highestRHeq used (93%), but when dried to lower RHs the response declined to <50% of control fluorescence values. Notably, immediately following rehydration (0 h postrehydration), shoots were damaged below control levels of fluorescence regardless of theRHeq , thus implicating damage.CONCLUSIONS Life phases of the moss
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Abstract Mosses (Bryophyta) are a key group occupying an important phylogenetic position in land plant (embryophyte) evolution. The class Bryopsida represents the most diversified lineage, containing more than 95% of modern mosses, whereas other classes are species‐poor. Two branches with large numbers of gene duplications were elucidated by phylogenomic analyses, one in the ancestry of all mosses and another before the separation of the Bryopsida, Polytrichopsida, and Tetraphidopsida. The analysis of the phylogenetic progression of duplicated paralogs retained on genomic syntenic regions in the
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Ultraviolet radiation (UVR) is a major environmental stressor for terrestrial plants. Here we investigated genetic responses to acute broadband UVR exposure in the highly desiccation-tolerant mosses Syntrichia caninervis and Syntrichia ruralis , using a comparative transcriptomics approach. We explored whether UVR protection is physiologically plastic and induced by UVR exposure, addressing the following questions: (1) What is the timeline of changes in the transcriptome with acute UVR exposure in these two species? (2) What genes are involved in the UVR response? and (3) How do the two species differ in their transcriptomic response to UVR? There were remarkable differences between the two species after 10 and 30 min of UVR exposure, including no overlap in significantly differentially abundant transcripts (DATs) after 10 min of UVR exposure and more than twice as many DATs for S. caninervis as there were for S. ruralis . Photosynthesis-related transcripts were involved in the response of S. ruralis to UVR, while membrane-related transcripts were indicated in the response of S. caninervis . In both species, transcripts involved in oxidative stress and those important for desiccation tolerance (such as late embryogenesis abundant genes and early light-inducible protein genes) were involved in response to UVR, suggesting possible roles in UVR tolerance and cross-talk with desiccation tolerance in these species. The results of this study suggest potential UVR-induced responses that may have roles outside of UVR tolerance, and that the response to URV is different in these two species, perhaps a reflection of adaptation to different environmental conditions.more » « less
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Summary Hornworts are crucial to understand the phylogeny of early land plants. The emergence of ‘reverse’ U‐to‐C RNA editing accompanying the widespread C‐to‐U RNA editing in plant chloroplasts and mitochondria may be a molecular synapomorphy of a hornwort–tracheophyte clade. C‐to‐U RNA editing is well understood after identification of many editing factors in models like
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