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Zhang R, Rao S, Wang Y, Qin Y, Qin K, Chen J. Chromosome Doubling Enhances Biomass and Carotenoid Content in Lycium chinense. PLANTS (BASEL, SWITZERLAND) 2024; 13:439. [PMID: 38337972 PMCID: PMC10857560 DOI: 10.3390/plants13030439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 01/26/2024] [Accepted: 01/30/2024] [Indexed: 02/12/2024]
Abstract
Lycium chinense, a type of medicinal and edible plant, is rich in bioactive compounds beneficial to human health. In order to meet the market requirements for the yield and quality of L. chinense, polyploid induction is usually an effective way to increase plant biomass and improve the content of bioactive components. This study established the most effective tetraploid induction protocol by assessing various preculture durations, colchicine concentrations, and exposure times. The peak tetraploid induction efficacy, 18.2%, was achieved with a 12-day preculture and 24-h exposure to 50 mg L-1 colchicine. Compared to diploids, tetraploids exhibited potentially advantageous characteristics such as larger leaves, more robust stems, and faster growth rates. Physiologically, tetraploids demonstrated increased stomatal size and chloroplast count in stomata but reduced stomatal density. Nutrient analysis revealed a substantial increase in polysaccharides, calcium, iron, and zinc in tetraploid leaves. In addition, seventeen carotenoids were identified in the leaves of L. chinense. Compared to the diploid, lutein, β-carotene, neoxanthin, violaxanthin, and (E/Z)-phytoene exhibited higher levels in tetraploid strains T39 and T1, with T39 demonstrating a greater accumulation than T1. The findings suggest that the generated tetraploids harbor potential for further exploitation and lay the foundation for the selection and breeding of novel genetic resources of Lycium.
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Affiliation(s)
- Runan Zhang
- State Key Laboratory of Efficient Production of Forest Resources, National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; (R.Z.); (S.R.); (Y.W.); (Y.Q.)
| | - Shupei Rao
- State Key Laboratory of Efficient Production of Forest Resources, National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; (R.Z.); (S.R.); (Y.W.); (Y.Q.)
| | - Yuchang Wang
- State Key Laboratory of Efficient Production of Forest Resources, National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; (R.Z.); (S.R.); (Y.W.); (Y.Q.)
| | - Yingzhi Qin
- State Key Laboratory of Efficient Production of Forest Resources, National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; (R.Z.); (S.R.); (Y.W.); (Y.Q.)
| | - Ken Qin
- National Wolfberry Engineering Research Center, Ningxia Academy of Agriculture and Forestry Sciences, Yinchuan 750002, China;
| | - Jinhuan Chen
- State Key Laboratory of Efficient Production of Forest Resources, National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; (R.Z.); (S.R.); (Y.W.); (Y.Q.)
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Kara Z, Doğan O. Mutagenic effects of nitrogen protoxide and oryzalin on "41 B" and "Fercal" grapevine rootstocks seedlings. BREEDING SCIENCE 2023; 73:355-364. [PMID: 38106510 PMCID: PMC10722092 DOI: 10.1270/jsbbs.23003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 05/08/2023] [Indexed: 12/19/2023]
Abstract
In this study, the mutagenic effects of different doses and exposure times of oryzalin and Nitrogen Protoxide (N2O) were tested for stimulating polyploid on 41 B and Fercal grapevine rootstocks seedlings. Ploidy changes were examined by morphological, cytological, macroscopic, and microscopic methods. Leaf thickness, chlorophyll contents, stomatal sizes, and chloroplast numbers of polyploid seedlings stimulated with mutagens increased but their stomatal densities decreased. Flow cytometry (FC) analyses were performed on 50 samples selected by morphological and microscopic preliminary determinations. In FC analyses, 1 tetraploid seedling and 4 mixoploid seedlings from Fercal offspring and 1 mixoploid seedling from 41 B offspring were verified. The nuclear DNA content of tetraploid and mixoploid seedlings were increased by 2.00 and 1.34-fold, respectively, when compared to their diploid parents. Chromosome counts in root tip samples propagated in vitro from the tetraploid Fercal offspring confirmed a 2-fold increase compared to the diploid parent. In polyploidy induction studies, it was deemed appropriate to use FC analysis and chromosome count together to confirm the ploidy levels of mutants. Oryzalin and N2O applications at different doses and exposure times were found to be effective for inducing polyploidy in 41 B and Fercal grapevine rootstocks.
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Affiliation(s)
- Zeki Kara
- Department of Horticulture, Faculty of Agriculture, Selcuk University, Konya, 42250, Turkey
| | - Osman Doğan
- Department of Horticulture, Faculty of Agriculture, Selcuk University, Konya, 42250, Turkey
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3
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Wu H, Jiang L, Li J, Lu M, An H. Polyploid Induction and Identification of Rosa roxburghii f. eseiosa. PLANTS (BASEL, SWITZERLAND) 2023; 12:plants12112194. [PMID: 37299173 DOI: 10.3390/plants12112194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 05/29/2023] [Accepted: 05/29/2023] [Indexed: 06/12/2023]
Abstract
Rosa roxburghii f. eseiosa Ku is a variety of Rosa roxburghii, with two known genotypes: Wuci 1 and Wuci 2. The lack of prickle on the peel of R. roxburghii f. eseiosa makes it easy to pick and process, but its fruit size is small. Therefore, we aim to induce polyploidy in order to obtain a larger fruit variety of R. roxburghii f. eseiosa. In this study, current-year stems of Wuci 1 and Wuci 2 were used as materials for polyploid induction, which was carried out through colchicine treatment coupled with tissue culture and rapid propagation technology. Impregnation and smearing methods were effectively used to produce polyploids. Using flow cytometry and a chromosome counting method, it was found that one autotetraploid of Wuci 1 (2n = 4x = 28) was obtained by the impregnation method before primary culture, with a variation rate of 1.11%. Meanwhile, seven Wuci 2 bud mutation tetraploids (2n = 4x = 28) were produced by smearing methods during the training seedling stage. When tissue-culture seedlings were treated with 20 mg/L colchicine for 15 days, the highest polyploidy rate was up to 60%. Morphological differences between different ploidys were observed. The side leaflet shape index, guard cell length, and stomatal length of the Wuci 1 tetraploid were significantly different from those of the Wuci 1 diploid. The terminal leaflet width, terminal leaflet shape index, side leaflet length, side leaflet width, guard cell length, guard cell width, stomatal length, and stomatal width of the Wuci 2 tetraploid were significantly different from those of the Wuci 2 diploid. Additionally, the leaf color of the Wuci 1 and Wuci 2 tetraploids changed from light to dark, with an initial decrease in chlorophyll content followed by an increase. In summary, this study established an effective method for inducing polyploids in R. roxburghii f. eseiosa, which could provide a foundation for the breeding and development of new genetic resources for R. roxburghii f. eseiosa and other R. roxburghii varieties in the future.
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Affiliation(s)
- Huijing Wu
- Agricultural College, Guizhou University, Guiyang 550025, China
| | - Lanlan Jiang
- Agricultural College, Guizhou University, Guiyang 550025, China
| | - Jin'e Li
- Agricultural College, Guizhou University, Guiyang 550025, China
| | - Min Lu
- Agricultural College, Guizhou University, Guiyang 550025, China
| | - Huaming An
- National Forestry and Grassland Administration Engineering Research Center for Rosa roxburghii, Guiyang 550025, China
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Morphological, Transcriptome, and Hormone Analysis of Dwarfism in Tetraploids of Populus alba × P. glandulosa. Int J Mol Sci 2022; 23:ijms23179762. [PMID: 36077160 PMCID: PMC9456051 DOI: 10.3390/ijms23179762] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 08/21/2022] [Accepted: 08/25/2022] [Indexed: 11/28/2022] Open
Abstract
Breeding for dwarfism is an important approach to improve lodging resistance. Here, we performed comparative analysis of the phenotype, transcriptome, and hormone contents between diploids and tetraploids of poplar 84K (Populus alba × P. glandulosa). Compared with diploids, the indole-3-acetic acid (IAA) and gibberellin (GA3) contents were increased, whereas the jasmonic acid (JA) and abscisic acid (ABA) contents were decreased in tetraploids. RNA-sequencing revealed that differentially expressed genes (DEGs) in leaves of tetraploids were mainly involved in plant hormone pathways. Most DEGs associated with IAA and GA promotion of plant growth and development were downregulated, whereas most DEGs associated with ABA and JA promotion of plant senescence were upregulated. Weighted gene co-expression network analysis indicated that certain transcription factors may be involved in the regulation of genes involved in plant hormone pathways. Thus, the altered expression of some genes in the plant hormone pathways may lead to a reduction in IAA and GA contents, as well as an elevation in ABA and JA contents, resulting in the dwarfing of tetraploids. The results show that polyploidization is a complex biological process affected by multiple plant hormone signals, and it provides a foundation for further exploration of the mechanism of tetraploids dwarfing in forest trees.
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Chen S, Zhang Y, Zhang T, Zhan D, Pang Z, Zhao J, Zhang J. Comparative Transcriptomic, Anatomical and Phytohormone Analyses Provide New Insights Into Hormone-Mediated Tetraploid Dwarfing in Hybrid Sweetgum ( Liquidambar styraciflua × L. formosana). FRONTIERS IN PLANT SCIENCE 2022; 13:924044. [PMID: 35832220 PMCID: PMC9271929 DOI: 10.3389/fpls.2022.924044] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 05/24/2022] [Indexed: 06/15/2023]
Abstract
Polyploid breeding is an effective approach to improve plant biomass and quality. Both fast growth and dwarf types of in vitro or ex vitro plants are produced after polyploidization. However, little is known regarding the dwarf type mechanism in polyploids grown in vitro. In this study, the morphological and cytological characteristics were measured in tetraploid and diploid hybrid sweetgum (Liquidambar styraciflua × L. formosana) with the same genetic background. RNA sequencing (RNA-Seq) was used to analyse shoot and root variations between tetraploid and diploid plants; important metabolites were validated. The results showed that the shoot and root lengths were significantly shorter in tetraploids than in diploids after 25 d of culture. Most tetraploid root cells were wider and more irregular, and the length of the meristematic zone was shorter, while tetraploid cells were significantly larger than diploid cells. Differentially expressed genes (DEGs) were significantly enriched in the plant growth and organ elongation pathways, such as plant hormone biosynthesis and signal transduction, sugar and starch metabolism, and cell cycles. Hormone biosynthesis and signal transduction genes, such as YUCCA, TAA1, GH3, SAUR, CPS, KO, KAO, GA20ox, GA3ox, BAS1 and CYCD3, which help to regulate organ elongation, were generally downregulated. The auxin, gibberellin, and brassinolide (BL) contents in roots and stems were significantly lower in tetraploids than in diploids, which may greatly contribute to slow growth in the roots and stems of tetraploid regenerated plants. Exogenous gibberellic acid (GA3) and indole-3-acetic acid (IAA), which induced plant cell elongation, could significantly promote growth in the stems and roots of tetraploids. In summary, comparative transcriptomics and metabolite analysis showed that the slow growth of regenerated tetraploid hybrid sweetgum was strongly related to auxin and gibberellin deficiency. Our findings provide insights into the molecular mechanisms that underlie dwarfism in allopolyploid hybrid sweetgum.
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Affiliation(s)
- Siyuan Chen
- National Engineering Research Center of Tree Breeding and Ecological Restoration, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
| | - Yan Zhang
- National Engineering Research Center of Tree Breeding and Ecological Restoration, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
- College of Landscape Architecture, Beijing University of Agriculture, Beijing, China
| | - Ting Zhang
- National Engineering Research Center of Tree Breeding and Ecological Restoration, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
| | - Dingju Zhan
- Guangxi Bagui Forest and Flowers Seedlings Co., Ltd., Nanning, China
| | - Zhenwu Pang
- Guangxi Bagui Forest and Flowers Seedlings Co., Ltd., Nanning, China
| | - Jian Zhao
- National Engineering Research Center of Tree Breeding and Ecological Restoration, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
| | - Jinfeng Zhang
- National Engineering Research Center of Tree Breeding and Ecological Restoration, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
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Wen Y, Liu H, Meng H, Qiao L, Zhang G, Cheng Z. In vitro Induction and Phenotypic Variations of Autotetraploid Garlic ( Allium sativum L.) With Dwarfism. FRONTIERS IN PLANT SCIENCE 2022; 13:917910. [PMID: 35812906 PMCID: PMC9258943 DOI: 10.3389/fpls.2022.917910] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 05/23/2022] [Indexed: 05/16/2023]
Abstract
Garlic (Allium sativum L.) is a compelling horticultural crop with high culinary and therapeutic values. Commercial garlic varieties are male-sterile and propagated asexually from individual cloves or bulbils. Consequently, its main breeding strategy has been confined to the time-consuming and inefficient selection approach from the existing germplasm. Polyploidy, meanwhile, plays a prominent role in conferring plants various changes in morphological, physiological, and ecological properties. Artificial polyploidy induction has gained pivotal attention to generate new genotype for further crop improvement as a mutational breeding method. In our study, efficient and reliable in vitro induction protocols of autotetraploid garlic were established by applying different antimitotic agents based on high-frequency direct shoot organogenesis initiated from inflorescence explant. The explants were cultured on solid medium containing various concentrations of colchicine or oryzalin for different duration days. Afterward, the ploidy levels of regenerated plantlets with stable and distinguished characters were confirmed by flow cytometry and chromosome counting. The colchicine concentration at 0.2% (w/v) combined with culture duration for 20 days was most efficient (the autotetraploid induction rate was 21.8%) compared to the induction rate of 4.3% using oryzalin at 60 μmol L-1 for 20 days. No polymorphic bands were detected by simple sequence repeat analysis between tetraploid and diploid plantlets. The tetraploids exhibited a stable and remarkable dwarfness effect rarely reported in artificial polyploidization among wide range of phenotypic variations. There are both morphological and cytological changes including extremely reduced plant height, thickening and broadening of leaves, disappearance of pseudostem, density reduction, and augmented width of stomatal. Furthermore, the level of phytohormones, including, indole propionic acid, gibberellin, brassinolide, zeatin, dihydrozeatin, and methyl jasmonate, was significantly lower in tetraploids than those in diploid controls, except indole acetic acid and abscisic acid, which could partly explain the dwarfness in hormonal regulation aspect. Moreover, as the typical secondary metabolites of garlic, organosulfur compounds including allicin, diallyl disulfide, and diallyl trisulfide accumulated a higher content significantly in tetraploids. The obtained dwarf genotype of autotetraploid garlic could bring new perspectives for the artificial polyploids breeding and be implemented as a new germplasm to facilitate investigation into whole-genome doubling consequences.
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Affiliation(s)
- Yanbin Wen
- College of Horticulture, Northwest A&F University, Xianyang, China
- Development Center of Fruit Vegetable and Herbal Tea, Datong, China
| | - Hongjiu Liu
- College of Horticulture, Northwest A&F University, Xianyang, China
| | - Huanwen Meng
- College of Horticulture, Northwest A&F University, Xianyang, China
| | - Lijun Qiao
- College of Horticulture, Northwest A&F University, Xianyang, China
| | - Guoqing Zhang
- Business School, Shanxi Datong University, Datong, China
| | - Zhihui Cheng
- College of Horticulture, Northwest A&F University, Xianyang, China
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Eng WH, Ho WS, Ling KH. In vitro induction and identification of polyploid Neolamarckia cadamba plants by colchicine treatment. PeerJ 2021; 9:e12399. [PMID: 34760387 PMCID: PMC8556713 DOI: 10.7717/peerj.12399] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 10/06/2021] [Indexed: 11/20/2022] Open
Abstract
Polyploidization has played a crucial role in plant breeding and crop improvement. However, studies on the polyploidization of tropical tree species are still very scarce in this region. This paper described the in vitro induction and identification of polyploid plants of Neolamarckia cadamba by colchicine treatment. N. cadamba belongs to the Rubiaceae family is a natural tetraploid plant with 44 chromosomes (2n = 4x = 44). Nodal segments were treated with colchicine (0.1%, 0.3% and 0.5%) for 24 h and 48 h before transferring to shoot regeneration medium. Flow cytometry (FCM) and chromosome count were employed to determine the ploidy level and chromosome number of the regenerants, respectively. Of 180 colchicine-treated nodal segments, 39, 14 and 22 were tetraploids, mixoploids and octoploids, respectively. The highest percentage of polyploidization (20% octoploids; 6.7% mixoploids) was observed after treated with 0.3% colchicine for 48 h. The DNA content of tetraploid (4C) and octoploid (8C) was 2.59 ± 0.09 pg and 5.35 ± 0.24 pg, respectively. Mixoploid plants are made up of mixed tetraploid and octoploid cells. Chromosome count confirmed that tetraploid cell has 44 chromosomes and colchicine-induced octoploid cell has 88 chromosomes. Both octoploids and mixoploids grew slower than tetraploids under in vitro conditions. Morphological characterizations showed that mixoploid and octoploid leaves had thicker leaf blades, thicker midrib, bigger stomata size, lower stomata density, higher SPAD value and smaller pith layer than tetraploids. This indicates that polyploidization has changed and resulted in traits that are predicted to increase photosynthetic capacity of N. cadamba. These novel polyploid plants could be valuable resources for advanced N. cadamba breeding programs to produce improved clones for planted forest development.
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Affiliation(s)
- Wee Hiang Eng
- Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, Kota Samarahan, Sarawak, Malaysia
| | - Wei Seng Ho
- Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, Kota Samarahan, Sarawak, Malaysia
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Rao S, Li Y, Chen J. Combined Analysis of MicroRNAs and Target Genes Revealed miR156-SPLs and miR172-AP2 Are Involved in a Delayed Flowering Phenomenon After Chromosome Doubling in Black Goji ( Lycium ruthencium). Front Genet 2021; 12:706930. [PMID: 34335704 PMCID: PMC8320596 DOI: 10.3389/fgene.2021.706930] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Accepted: 06/14/2021] [Indexed: 02/04/2023] Open
Abstract
Polyploidy, which is widely distributed in angiosperms, presents extremely valuable commercial applications in plant growth and reproduction. The flower development process of higher plants is essential for genetic improvement. Nevertheless, the reproduction difference between polyploidy and the polyploid florescence regulatory network from the perspective of microRNA (miRNA) remains to be elucidated. In this study, the autotetraploid of Lycium ruthenicum showed late-flowering traits compared with the progenitor. Combining the association of miRNA and next-generation transcriptome technology, the late-flowering characteristics triggered by chromosome duplication may be caused by the age pathway involved in miR156-SPLs and miR172-AP2, which inhibits the messenger RNA (mRNA) transcripts of FT in the leaves. Subsequently, FT was transferred to the shoot apical meristem (SAM) to inhibit the expression of the flowering integration factor SOC1, which can eventually result in delayed flowering time. Our exploration of the flowering regulation network and the control of the flowering time are vital to the goji producing in the late frost area, which provides a new perspective for exploring the intrinsic molecular mechanism of polyploid and the reproductive development of flowering plants.
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Affiliation(s)
- Shupei Rao
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China.,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China
| | - Yue Li
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China.,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China
| | - Jinhuan Chen
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China.,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China
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Glazier DS. Genome Size Covaries More Positively with Propagule Size than Adult Size: New Insights into an Old Problem. BIOLOGY 2021; 10:270. [PMID: 33810583 PMCID: PMC8067107 DOI: 10.3390/biology10040270] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/18/2021] [Accepted: 03/23/2021] [Indexed: 12/17/2022]
Abstract
The body size and (or) complexity of organisms is not uniformly related to the amount of genetic material (DNA) contained in each of their cell nuclei ('genome size'). This surprising mismatch between the physical structure of organisms and their underlying genetic information appears to relate to variable accumulation of repetitive DNA sequences, but why this variation has evolved is little understood. Here, I show that genome size correlates more positively with egg size than adult size in crustaceans. I explain this and comparable patterns observed in other kinds of animals and plants as resulting from genome size relating strongly to cell size in most organisms, which should also apply to single-celled eggs and other reproductive propagules with relatively few cells that are pivotal first steps in their lives. However, since body size results from growth in cell size or number or both, it relates to genome size in diverse ways. Relationships between genome size and body size should be especially weak in large organisms whose size relates more to cell multiplication than to cell enlargement, as is generally observed. The ubiquitous single-cell 'bottleneck' of life cycles may affect both genome size and composition, and via both informational (genotypic) and non-informational (nucleotypic) effects, many other properties of multicellular organisms (e.g., rates of growth and metabolism) that have both theoretical and practical significance.
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Rao S, Tian Y, Xia X, Li Y, Chen J. Chromosome doubling mediates superior drought tolerance in Lycium ruthenicum via abscisic acid signaling. HORTICULTURE RESEARCH 2020; 7:40. [PMID: 32257226 PMCID: PMC7109118 DOI: 10.1038/s41438-020-0260-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 01/19/2020] [Accepted: 01/26/2020] [Indexed: 05/05/2023]
Abstract
Plants are continuously affected by unfavorable external stimuli, which influences their productivity and growth. Differences in gene composition and expression patterns lead homologous polyploid plants to exhibit different physiological phenomena, among which enhanced environmental adaptability is a powerful phenotype conferred by polyploidization. The mechanisms underlying the differences in stress tolerance between diploids and autotetraploids at the molecular level remain unclear. In this research, a full-length transcription profile obtained via the single-molecule real-time (SMRT) sequencing of high-quality single RNA molecules for use as background was combined with next-generation transcriptome and proteome technologies to probe the variation in the molecular mechanisms of autotetraploids. Tetraploids exhibited an increase in ABA content of 78.4% under natural conditions and a superior stress-resistance phenotype under severe drought stress compared with diploids. The substantial differences in the transcriptome profiles observed between diploids and autotetraploids under normal growth conditions were mainly related to ABA biosynthesis and signal transduction pathways, and 9-cis-epoxycarotenoid dioxygenase 1 (NCED1) and NCED2, which encode key synthetic enzymes, were significantly upregulated. The increased expression of the ABRE-binding factor 5-like (ABF5-like) gene was a pivotal factor in promoting the activation of the ABA signaling pathway and downstream target genes. In addition, ABA strongly induced the expression of osmotic proteins to increase the stress tolerance of the plants at the translational level. We consider the intrinsic mechanisms by which ABA affects drought resistance in tetraploids and diploids to understand the physiological and molecular mechanisms that enhance abiotic stress tolerance in polyploid plants.
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Affiliation(s)
- Shupei Rao
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, 100083 Beijing, China
- College of Biological Sciences and Technology, Beijing Forestry University, 100083 Beijing, China
- National Engineering Laboratory for Tree Breeding, Beijing Forestry University, 100083 Beijing, China
| | - Yuru Tian
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, 100083 Beijing, China
- College of Biological Sciences and Technology, Beijing Forestry University, 100083 Beijing, China
- National Engineering Laboratory for Tree Breeding, Beijing Forestry University, 100083 Beijing, China
| | - Xinli Xia
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, 100083 Beijing, China
- College of Biological Sciences and Technology, Beijing Forestry University, 100083 Beijing, China
- National Engineering Laboratory for Tree Breeding, Beijing Forestry University, 100083 Beijing, China
| | - Yue Li
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, 100083 Beijing, China
- College of Biological Sciences and Technology, Beijing Forestry University, 100083 Beijing, China
- National Engineering Laboratory for Tree Breeding, Beijing Forestry University, 100083 Beijing, China
| | - Jinhuan Chen
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, 100083 Beijing, China
- College of Biological Sciences and Technology, Beijing Forestry University, 100083 Beijing, China
- National Engineering Laboratory for Tree Breeding, Beijing Forestry University, 100083 Beijing, China
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