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Lipids are essential for plant growth, signaling, development and environmental adaptation. Plant and algal lipids are also at the core of our energy economy, as polar lipids form photosynthetic membranes while neutral storage lipids (i.e. triacylglycerols, TAGs) represent an energy-dense reservoir of reduced carbon and fuel; as such, they additionally serve as important renewable sources of food, feed, biofuel and industrial feedstocks. These benefits, which are critical to human society, underscore the importance of understanding how lipids are produced and function within plants. Recent advances in lipidomics and lipid imaging, coupled with the development of high throughput, low-cost genome sequencing tools and genome-editing techniques now enable a deeper appreciation of the role of lipids at all scales and in all their states (e.g. as membrane, storage and signaling components). This Special Issue of Plant and Cell Physiology provides a holistic view of plant and algal lipids, especially in terms of their adaptation to environmental challenges. This issue includes three review papers and 12 research articles covering areas from the regulation of lipid synthesis, enzyme structural determinants to the role of lipids in stress management and its relation to photosynthesis.
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Burning questions for a warming and changing world: 15 unknowns in plant abiotic stress
Abstract We present unresolved questions in plant abiotic stress biology as posed by 15 research groups with expertise spanning eco-physiology to cell and molecular biology. Common themes of these questions include the need to better understand how plants detect water availability, temperature, salinity, and rising carbon dioxide (CO2) levels; how environmental signals interface with endogenous signaling and development (e.g. circadian clock and flowering time); and how this integrated signaling controls downstream responses (e.g. stomatal regulation, proline metabolism, and growth versus defense balance). The plasma membrane comes up frequently as a site of key signaling and transport events (e.g. mechanosensing and lipid-derived signaling, aquaporins). Adaptation to water extremes and rising CO2 affects hydraulic architecture and transpiration, as well as root and shoot growth and morphology, in ways not fully understood. Environmental adaptation involves tradeoffs that limit ecological distribution and crop resilience in the face of changing and increasingly unpredictable environments. Exploration of plant diversity within and among species can help us know which of these tradeoffs represent fundamental limits and which ones can be circumvented by bringing new trait combinations together. Better defining what constitutes beneficial stress resistance in different contexts and making connections between genes and phenotypes, and between laboratory and field observations, are overarching challenges.
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- PAR ID:
- 10408543
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Date Published:
- Journal Name:
- The Plant Cell
- Volume:
- 35
- Issue:
- 1
- ISSN:
- 1040-4651
- Page Range / eLocation ID:
- 67 to 108
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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SUMMARY The KARRIKIN INSENSITIVE 2 (KAI2) receptor, originally characterized for its role in seed germination and light‐responsive development, is now recognized as an important signaling component with broad physiological relevance across plant species. While KAI2 is perhaps best known for perceiving exogenous smoked‐derived karrikins, recent discoveries have revealed extensive crosstalk between KAI2‐mediated signaling and multiple phytohormone pathways. We synthesize the current knowledge of KAI2 crosstalk with core plant hormones like strigolactones, auxin, ethylene, gibberellins, abscisic acid, cytokinins, and salicylic acid. We highlight shared signaling components, transcriptional regulation, and physiological outcomes. We examine how KAI2 signaling modulates hormone signaling and discuss the emerging view of KAI2 as an integrator of environmental and hormonal cues, particularly in stress adaptation and developmental plasticity. Finally, we propose new approaches, including proximity‐labeling screens to dissect KAI2's full signaling potential and to explore open questions surrounding the identity and regulation of the endogenous putative KAI2 ligand. These insights position KAI2 as an evolving hub in the plant‐signaling network, with implications for both fundamental research and crop improvement.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1093/plcell/koac263
