The altered carbon assimilation pathway of crassulacean acid metabolism (
- Award ID(s):
- 1833402
- NSF-PAR ID:
- 10314415
- Date Published:
- Journal Name:
- BioDesign Research
- Volume:
- 2020
- ISSN:
- 2693-1257
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Summary CAM ) photosynthesis results in an up to 80% higher water‐use efficiency than C3photosynthesis in plants making it a potentially useful pathway for engineering crop plants with improved drought tolerance. Here we surveyed detailed temporal (diel time course) and spatial (across a leaf gradient) gene and microRNA (miRNA ) expression patterns in the obligateCAM plant pineapple [Ananas comosus (L.) Merr.]. The high‐resolution transcriptome atlas allowed us to distinguish betweenCAM ‐related and non‐CAM gene copies. A differential gene co‐expression network across green and white leaf diel datasets identified genes with circadian oscillation,CAM ‐related functions, and source‐sink relations. Gene co‐expression clusters containingCAM pathway genes are enriched with clock‐associatedcis ‐elements, suggesting circadian regulation ofCAM . About 20% of pineapple microRNA s have diel expression patterns, with several that target keyCAM ‐related genes. Expression and physiology data provide a model forCAM ‐specific carbohydrate flux and long‐distance hexose transport. Together these resources provide a list of candidate genes for targeted engineering ofCAM into C3photosynthesis crop species. -
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Abstract The number of plant species with genomic and transcriptomic data has been increasing rapidly. The grasses—Poaceae—have been well represented among species with published reference genomes. However, as a result the genomes of wild grasses are less frequently targeted by sequencing efforts. Sequence data from wild relatives of crop species in the grasses can aid the study of domestication, gene discovery for breeding and crop improvement, and improve our understanding of the evolution of C4photosynthesis. Here, we used long‐read sequencing technology to characterize the transcriptomes of three C3panicoid grass species:
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Photosynthetic organisms are sources of sustainable foods, renewable biofuels, novel biopharmaceuticals, and next-generation biomaterials essential for modern society. Efforts to improve the yield, variety, and sustainability of products dependent on chloroplasts are limited by the need for biotechnological approaches for high-throughput chloroplast transformation, monitoring chloroplast function, and engineering photosynthesis across diverse plant species. The use of nanotechnology has emerged as a novel approach to overcome some of these limitations. Nanotechnology is enabling advances in the targeted delivery of chemicals and genetic elements to chloroplasts, nanosensors for chloroplast biomolecules, and nanotherapeutics for enhancing chloroplast performance. Nanotechnology-mediated delivery of DNA to the chloroplast has the potential to revolutionize chloroplast synthetic biology by allowing transgenes, or even synthesized DNA libraries, to be delivered to a variety of photosynthetic species. Crop yield improvements could be enabled by nanomaterials that enhance photosynthesis, increase tolerance to stresses, and act as nanosensors for biomolecules associated with chloroplast function. Engineering isolated chloroplasts through nanotechnology and synthetic biology approaches are leading to a new generation of plant-based biomaterials able to self-repair using abundant CO 2 and water sources and are powered by renewable sunlight energy. Current knowledge gaps of nanotechnology-enabled approaches for chloroplast biotechnology include precise mechanisms for entry into plant cells and organelles, limited understanding about nanoparticle-based chloroplast transformations, and the translation of lab-based nanotechnology tools to the agricultural field with crop plants. Future research in chloroplast biotechnology mediated by the merging of synthetic biology and nanotechnology approaches can yield tools for precise control and monitoring of chloroplast function in vivo and ex vivo across diverse plant species, allowing increased plant productivity and turning plants into widely available sustainable technologies.more » « less
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Abstract Uncertainty about long‐term leaf‐level responses to atmospheric CO2rise is a major knowledge gap that exists because of limited empirical data. Thus, it remains unclear how responses of leaf gas exchange to elevated CO2(eCO2) vary among plant species and functional groups, or across different levels of nutrient supply, and whether they persist over time for long‐lived perennials. Here, we report the effects of eCO2on rates of net photosynthesis and stomatal conductance in 14 perennial grassland species from four functional groups over two decades in a Minnesota Free‐Air CO2Enrichment experiment, BioCON. Monocultures of species belonging to C3grasses, C4grasses, forbs, and legumes were exposed to two levels of CO2and nitrogen supply in factorial combinations over 21 years. eCO2increased photosynthesis by 12.9% on average in C3species, substantially less than model predictions of instantaneous responses based on physiological theory and results of other studies, even those spanning multiple years. Acclimation of photosynthesis to eCO2was observed beginning in the first year and did not strengthen through time. Yet, contrary to expectations, the response of photosynthesis to eCO2was not enhanced by increased nitrogen supply. Differences in responses among herbaceous plant functional groups were modest, with legumes responding the most and C4grasses the least as expected, but did not further diverge over time. Leaf‐level water‐use efficiency increased by 50% under eCO2primarily because of reduced stomatal conductance. Our results imply that enhanced nitrogen supply will not necessarily diminish photosynthetic acclimation to eCO2in nitrogen‐limited systems, and that significant and consistent declines in stomatal conductance and increases in water‐use efficiency under eCO2may allow plants to better withstand drought.
- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.34133/2020/3686791
