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Shi C, Xie Y, Guan D, Qin G. Transcriptomic Analysis Reveals Adaptive Evolution and Conservation Implications for the Endangered Magnolia lotungensis. Genes (Basel) 2024; 15:787. [PMID: 38927723 PMCID: PMC11203017 DOI: 10.3390/genes15060787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 06/03/2024] [Accepted: 06/13/2024] [Indexed: 06/28/2024] Open
Abstract
Magnolia lotungensis is an extremely endangered endemic tree in China. To elucidate the genetic basis of M. lotungensis, we performed a comprehensive transcriptome analysis using a sample integrating the plant's bark, leaves, and flowers. De novo transcriptome assembly yielded 177,046 transcripts and 42,518 coding sequences. Notably, we identified 796 species-specific genes enriched in organelle gene regulation and defense responses. A codon usage bias analysis revealed that mutation bias appears to be the primary driver of selection in shaping the species' genetic architecture. An evolutionary analysis based on dN/dS values of paralogous and orthologous gene pairs indicated a predominance of purifying selection, suggesting strong evolutionary constraints on most genes. A comparative transcriptomic analysis with Magnolia sinica identified approximately 1000 ultra-conserved genes, enriched in essential cellular processes such as transcriptional regulation, protein synthesis, and genome stability. Interestingly, only a limited number of 511 rapidly evolving genes under positive selection were detected compared to M. sinica and Magnolia kuangsiensis. These genes were enriched in metabolic processes associated with adaptation to specific environments, potentially limiting the species' ability to expand its range. Our findings contribute to understanding the genetic architecture of M. lotungensis and suggest that an insufficient number of adaptive genes contribute to its endangered status.
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Affiliation(s)
- Chenyu Shi
- Guangxi Key Laboratory of Sericulture Ecology and Applied Intelligent Technology, Hechi University, Hechi 546300, China; (C.S.); (Y.X.)
- Guangxi Collaborative Innovation Center of Modern Sericulture and Silk, Hechi University, Hechi 546300, China
| | - Yanjun Xie
- Guangxi Key Laboratory of Sericulture Ecology and Applied Intelligent Technology, Hechi University, Hechi 546300, China; (C.S.); (Y.X.)
- Guangxi Collaborative Innovation Center of Modern Sericulture and Silk, Hechi University, Hechi 546300, China
| | - Delong Guan
- Guangxi Collaborative Innovation Center of Modern Sericulture and Silk, Hechi University, Hechi 546300, China
- School of Chemistry and Bioengineering, Hechi University, Hechi 546300, China
| | - Guole Qin
- Guangxi Key Laboratory of Sericulture Ecology and Applied Intelligent Technology, Hechi University, Hechi 546300, China; (C.S.); (Y.X.)
- Guangxi Collaborative Innovation Center of Modern Sericulture and Silk, Hechi University, Hechi 546300, China
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Guo J, Li H, Yang Y, Yang X. Clonal dominant grass Leymus chinensis benefits more from physiological integration in sexual reproduction than its main companions in a meadow. FRONTIERS IN PLANT SCIENCE 2023; 14:1205166. [PMID: 37636095 PMCID: PMC10452009 DOI: 10.3389/fpls.2023.1205166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 07/25/2023] [Indexed: 08/29/2023]
Abstract
The bioecological characteristics of plants determine their status and role in the community. The advantages of dominant species in the community compared with companion species in terms of physiological and ecological characteristics remain unclear. When both dominant and companion species in grassland plant communities are clonal, these plants are able to share resources within clones (physiological integration). However, it is unclear how the clonal dominant and companion species differ in the effect of their physiological integration on sexual reproduction. We chose Leymus chinensis, the dominant species of the most widespread meadow plant communities in the semiarid and arid regions of northern China, and its main companion species L. secalinus, Calamagrostis ripidula, C. pseudophragmites, and C. epigeios and conducted a series of in situ field experiments in a homogeneous environment, including the determination of the phenotypic characteristics of reproductive ramets with connected (allowing physiological integration) and disconnected (preventing integration) tillering nodes for each species, as well as 15N leaf labeling of ramet pairs at the milk-ripe stage. In the clonal populations of the five grasses, physiological integration between vegetative ramets and reproductive ramets interconnected by tillering nodes significantly increased the leaf, stem, inflorescence and ramet biomasses of reproductive ramets, and relative changes in ramet biomass were greatest in L. chinensis. 15N labeling showed that vegetative ramets supplied nutrients to reproductive ramets through tillering nodes; the amount of translocated 15N per unit of reproductive ramet biomass was highest in L. chinensis. Overall, our results indicate that in the five clonal grasses, physiological integration between functionally different ramets under tillering node connections had a significant positive effect on sexual reproduction, indicating interspecific consistency in the contribution of physiological integration to sexual reproduction between the dominant and companion species, but this positive effect was greater in the dominant species L. chinensis than in the four main companion species. Therefore, differences in the physiological integration ability between the dominant and main companion species, identified for the first time in this study, may explain, at least partly, the dominance of L. chinensis in the community.
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Affiliation(s)
- Jian Guo
- School of Environmental Engineering, Xuzhou University of Technology, Xuzhou, China
- Institute of Grassland Science, Key Laboratory of Vegetation Ecology of the Ministry of Education, Jilin Songnen Grassland Ecosystem National Observation and Research Station, Northeast Normal University, Changchun, China
| | - Haiyan Li
- Institute of Grassland Science, Key Laboratory of Vegetation Ecology of the Ministry of Education, Jilin Songnen Grassland Ecosystem National Observation and Research Station, Northeast Normal University, Changchun, China
| | - Yunfei Yang
- Institute of Grassland Science, Key Laboratory of Vegetation Ecology of the Ministry of Education, Jilin Songnen Grassland Ecosystem National Observation and Research Station, Northeast Normal University, Changchun, China
| | - Xuechen Yang
- State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin, China
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Jiang Z, Wang Y, Zheng Y, Cai M, Peng C, Li W. Physiological and transcriptomic responses of Mikania micrantha stem to shading yield novel insights into its invasiveness. Biol Invasions 2021. [DOI: 10.1007/s10530-021-02546-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ntawuhiganayo EB, Uwizeye FK, Zibera E, Dusenge ME, Ziegler C, Ntirugulirwa B, Nsabimana D, Wallin G, Uddling J. Traits controlling shade tolerance in tropical montane trees. TREE PHYSIOLOGY 2020; 40:183-197. [PMID: 31860725 PMCID: PMC7048680 DOI: 10.1093/treephys/tpz119] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 06/24/2019] [Accepted: 10/24/2019] [Indexed: 06/01/2023]
Abstract
Tropical canopies are complex, with multiple canopy layers and pronounced gap dynamics contributing to their high species diversity and productivity. An important reason for this complexity is the large variation in shade tolerance among different tree species. At present, we lack a clear understanding of which plant traits control this variation, e.g., regarding the relative contributions of whole-plant versus leaf traits or structural versus physiological traits. We investigated a broad range of traits in six tropical montane rainforest tree species with different degrees of shade tolerance, grown under three different radiation regimes (under the open sky or beneath sparse or dense canopies). The two distinct shade-tolerant species had higher fractional biomass in leaves and branches while shade-intolerant species invested more into stems, and these differences were greater under low radiation. Leaf respiration and photosynthetic light compensation point did not vary with species shade tolerance, regardless of radiation regime. Leaf temperatures in open plots were markedly higher in shade-tolerant species due to their low transpiration rates and large leaf sizes. Our results suggest that interspecific variation in shade tolerance of tropical montane trees is controlled by species differences in whole-plant biomass allocation strategy rather than by difference in physiological leaf traits determining leaf carbon balance at low radiation.
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Affiliation(s)
- Elisée Bahati Ntawuhiganayo
- Department of Biology, University of Rwanda, University Avenue, PO Box 117, Huye, Rwanda
- World Agroforestry (ICRAF), University Avenue PO Box 227, Huye, Rwanda
| | - Félicien K Uwizeye
- Department of Biology, University of Rwanda, University Avenue, PO Box 117, Huye, Rwanda
- BirdLife International, KG 501 St, PO Box 2527, Kigali, Rwanda
| | - Etienne Zibera
- Department of Biology, University of Rwanda, University Avenue, PO Box 117, Huye, Rwanda
| | - Mirindi E Dusenge
- Department of Biology, University of Rwanda, University Avenue, PO Box 117, Huye, Rwanda
- Department of Biology, University of Western Ontario, 1157 Richmond street, London, Ontario N6A 5B7, Canada
| | - Camille Ziegler
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, SE-405 30 Gothenburg, Sweden
- UMR EcoFoG, INRA, CNRS, Cirad, AgroParisTech, Université des Antilles, Université de Guyane, BP 709, 97387 Kourou Cedex, France
- Université de Lorraine, AgroParisTech, INRA, UMR Silva, 54000 Nancy, France
| | - Bonaventure Ntirugulirwa
- Department of Biology, University of Rwanda, University Avenue, PO Box 117, Huye, Rwanda
- Rwanda Agriculture and Animal Resources Development, PO Box 5016, Kigali, Rwanda
| | - Donat Nsabimana
- Department of Biology, University of Rwanda, University Avenue, PO Box 117, Huye, Rwanda
| | - Göran Wallin
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, SE-405 30 Gothenburg, Sweden
| | - Johan Uddling
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, SE-405 30 Gothenburg, Sweden
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