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Ge X, Du J, Zhang L, Qu G, Hu J. PeCLH2 Gene Positively Regulate Salt Tolerance in Transgenic Populus alba × Populus glandulosa. Genes (Basel) 2023; 14:genes14030538. [PMID: 36980811 PMCID: PMC10048402 DOI: 10.3390/genes14030538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/16/2023] [Accepted: 02/17/2023] [Indexed: 02/24/2023] Open
Abstract
Salt is an important environmental stress factor, which seriously affects the growth, development and distribution of plants. Chlorophyllase plays an important role in stress response. Nevertheless, little is known about the physiological and molecular mechanism of chlorophyll (Chlase, CLH) genes in plants. We cloned PeCLH2 from Populus euphratica and found that PeCLH2 was differentially expressed in different tissues, especially in the leaves of P. euphratica. To further study the role of PeCLH2 in salt tolerance, PeCLH2 overexpression and RNA interference transgenic lines were established in Populus alba × Populus glandulosa and used for salt stress treatment and physiologic indexes studies. Overexpressing lines significantly improved tolerance to salt treatment and reduced reactive oxygen species production. RNA interference lines showed the opposite. Transcriptome analysis was performed on leaves of control and transgenic lines under normal growth conditions and salt stress to predict genes regulated during salt stress. This provides a basis for elucidating the molecular regulation mechanism of PeCLH2 in response to salt stress and improving the tolerance of poplar under salt stress.
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Affiliation(s)
- Xiaolan Ge
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Xiangshan Road, Beijing 100091, China
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Hexing Road, Harbin 150040, China
| | - Jiujun Du
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Xiangshan Road, Beijing 100091, China
| | - Lei Zhang
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Xiangshan Road, Beijing 100091, China
- Collaborative Innovation Center of Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China
| | - Guanzheng Qu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Hexing Road, Harbin 150040, China
| | - Jianjun Hu
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Xiangshan Road, Beijing 100091, China
- Collaborative Innovation Center of Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China
- Correspondence: ; Tel.: +86-10-62888862
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2
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Zhu F, Alseekh S, Koper K, Tong H, Nikoloski Z, Naake T, Liu H, Yan J, Brotman Y, Wen W, Maeda H, Cheng Y, Fernie AR. Genome-wide association of the metabolic shifts underpinning dark-induced senescence in Arabidopsis. THE PLANT CELL 2022; 34:557-578. [PMID: 34623442 PMCID: PMC8774053 DOI: 10.1093/plcell/koab251] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 10/05/2021] [Indexed: 05/31/2023]
Abstract
Dark-induced senescence provokes profound metabolic shifts to recycle nutrients and to guarantee plant survival. To date, research on these processes has largely focused on characterizing mutants deficient in individual pathways. Here, we adopted a time-resolved genome-wide association-based approach to characterize dark-induced senescence by evaluating the photochemical efficiency and content of primary and lipid metabolites at the beginning, or after 3 or 6 days in darkness. We discovered six patterns of metabolic shifts and identified 215 associations with 81 candidate genes being involved in this process. Among these associations, we validated the roles of four genes associated with glycine, galactinol, threonine, and ornithine levels. We also demonstrated the function of threonine and galactinol catabolism during dark-induced senescence. Intriguingly, we determined that the association between tyrosine contents and TYROSINE AMINOTRANSFERASE 1 influences enzyme activity of the encoded protein and transcriptional activity of the gene under normal and dark conditions, respectively. Moreover, the single-nucleotide polymorphisms affecting the expression of THREONINE ALDOLASE 1 and the amino acid transporter gene AVT1B, respectively, only underlie the variation in threonine and glycine levels in the dark. Taken together, these results allow us to present a very detailed model of the metabolic aspects of dark-induced senescence, as well as the process itself.
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Affiliation(s)
- Feng Zhu
- National R&D Center for Citrus Preservation, Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam-Golm 14476, Germany
| | - Saleh Alseekh
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam-Golm 14476, Germany
- Center of Plant Systems Biology and Biotechnology, Plovdiv 4000, Bulgaria
| | - Kaan Koper
- Department of Botany, University of Wisconsin–Madison, Madison, Wisconsin 53706, USA
| | - Hao Tong
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam-Golm 14476, Germany
- Center of Plant Systems Biology and Biotechnology, Plovdiv 4000, Bulgaria
- Bioinformatics, Institute of Biochemistry and Biology, University of Potsdam, Potsdam 14476, Germany
| | - Zoran Nikoloski
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam-Golm 14476, Germany
- Center of Plant Systems Biology and Biotechnology, Plovdiv 4000, Bulgaria
- Bioinformatics, Institute of Biochemistry and Biology, University of Potsdam, Potsdam 14476, Germany
| | - Thomas Naake
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam-Golm 14476, Germany
| | - Haijun Liu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna 1030, Austria
| | - Jianbing Yan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Yariv Brotman
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam-Golm 14476, Germany
- Department of Life Sciences, Ben-Gurion University of the Negev, Beersheba, Israel
| | - Weiwei Wen
- National R&D Center for Citrus Preservation, Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China
| | - Hiroshi Maeda
- Department of Botany, University of Wisconsin–Madison, Madison, Wisconsin 53706, USA
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Hu X, Khan I, Jiao Q, Zada A, Jia T. Chlorophyllase, a Common Plant Hydrolase Enzyme with a Long History, Is Still a Puzzle. Genes (Basel) 2021; 12:genes12121871. [PMID: 34946820 PMCID: PMC8702186 DOI: 10.3390/genes12121871] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 11/20/2021] [Accepted: 11/22/2021] [Indexed: 02/01/2023] Open
Abstract
Chlorophyllase (Chlase, CLH) is one of the earliest discovered enzymes present in plants and green algae. It was long considered to be the first enzyme involved in chlorophyll (Chl) degradation, while strong evidence showed that it is not involved in Chl breakdown during leaf senescence. On the other hand, it is possible that CLH is involved in Chl breakdown during fruit ripening. Recently, it was discovered that Arabidopsis CLH1 is located in developing chloroplasts but not in mature chloroplasts, and it plays a role in protecting young leaves from long-term photodamage by catalysing Chl turnover in the photosystem II (PSII) repair cycle. However, there remain other important questions related to CLH. In this article, we briefly reviewed the research progress on CLH and listed the main unanswered questions related to CLH for further study.
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Affiliation(s)
- Xueyun Hu
- International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; (X.H.); (Q.J.)
- Laboratory of Plant Functional Genomics of the Ministry of Education, Yangzhou University, Yangzhou 225009, China
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China; (I.K.); (A.Z.)
| | - Imran Khan
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China; (I.K.); (A.Z.)
| | - Qingsong Jiao
- International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; (X.H.); (Q.J.)
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China; (I.K.); (A.Z.)
| | - Ahmad Zada
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China; (I.K.); (A.Z.)
| | - Ting Jia
- International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; (X.H.); (Q.J.)
- Laboratory of Plant Functional Genomics of the Ministry of Education, Yangzhou University, Yangzhou 225009, China
- Correspondence:
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Kamiab F, Tavassolian I, Hosseinifarahi M. Biologia futura: the role of polyamine in plant science. Biol Futur 2021; 71:183-194. [PMID: 34554509 DOI: 10.1007/s42977-020-00027-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Accepted: 06/10/2020] [Indexed: 12/27/2022]
Abstract
Polyamines (PAs) are positively charged amines such as putrescine, spermidine and spermine that ubiquitously exist in all organisms. They have been considered as a new type of plant biostimulants, with pivotal roles in many physiological processes. Polyamine levels are controlled by intricate regulatory feedback mechanisms. PAs are directly or indirectly regulated through interaction with signaling metabolites (H202, NO), aminobutyric acid (GABA), phytohormones (abscisic acid, gibberellins, ethylene, cytokinins, auxin, jasmonic acid and brassinosteroids) and nitrogen metabolism (maintaining the balance of C:N in plants). Exogenous applications of PAs enhance the stress resistance, flowering and fruit set, synthesis of bioactive compounds and extension of agricultural crops shelf life. Up-regulation of PAs biosynthesis by genetic manipulation can be a novel strategy to increase the productivity of agricultural crops. Recently, the role of PAs in symbiosis relationships between plants and beneficial microorganisms has been confirmed. PA metabolism has also been targeted to design new harmless fungicides.
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Affiliation(s)
- Fereshteh Kamiab
- Department of Horticulture, Faculty of Agriculture, Rafsanjan Branch, Islamic Azad University, Rafsanjan, Iran.
| | - Iraj Tavassolian
- Research and Technology Institute of Plant Production, Shahid Bahonar University of Kerman, Kerman, Iran.,Department of Horticulture, Faculty of Agriculture, Shahid Bahonar University of Kerman, Kerman, Iran
| | - Mehdi Hosseinifarahi
- Department of Horticultural Science, Yasooj Branch, Islamic Azad University, Yasooj, Iran
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5
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Ravindran SP, Tams V, Cordellier M. Transcriptome‐wide genotype–phenotype associations in
Daphnia
in a predation risk environment. J Evol Biol 2020; 34:879-892. [DOI: 10.1111/jeb.13699] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 08/03/2020] [Accepted: 08/29/2020] [Indexed: 12/30/2022]
Affiliation(s)
- Suda Parimala Ravindran
- Department of Marine Sciences Tjärnö Marine Laboratory University of Gothenburg Strömstad Sweden
| | - Verena Tams
- Institute of Marine Ecosystem and Fishery Science Universität Hamburg Hamburg Germany
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6
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Epigenetic Variation at a Genomic Locus Affecting Biomass Accumulation under Low Nitrogen in Arabidopsis thaliana. AGRONOMY-BASEL 2020. [DOI: 10.3390/agronomy10050636] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Nitrogen (N) is a macronutrient determining crop yield. The application of N fertilisers can substantially increase the yield, but excess use also causes the nitrate pollution of water resources and increases production costs. Increasing N use efficiency (NUE) in crop plants is an important step to implement low-input agricultural systems. We used Arabidopsis thaliana as model system to investigate the natural genetic diversity in traits related to NUE. Natural variation was used to study adaptive growth patterns and changes in gene expression associated with limited nitrate availability. A genome-wide association study revealed an association of eight SNP markers on Chromosome 1 with shoot growth under limited N. The identified linkage disequilibrium (LD) interval includes the DNA sequences of three cysteine/histidine-rich C1 domain proteins in tandem orientation. These genes differ in promoter structure, methylation pattern and expression level among accessions, correlating with growth performance under N deficiency. Our results suggest the involvement of epigenetic regulation in the expression of NUE-related traits.
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Wu Q, Zhao F, Zhu X, Zhou Z, Yang D, Xu Z, Li J, Qin Z. Design and synthesis of novel hydrocarbylidene nitrohydrazinecarboximidamides against aphids based on natural product galegine. Nat Prod Res 2019; 35:1484-1490. [PMID: 31429320 DOI: 10.1080/14786419.2019.1655409] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
A series of novel hydrocarbylidene nitrohydrazinecarboximidamides were designed and synthesized using an insecticidal natural product Galegine as a lead compound. The bioassay results show that the target compounds exhibited moderate to good insecticidal activities against Hyalopterus pruni Geoffroy at a concentration of 200 mg/L, and most compounds show excellet insecticidal activities against Aphis gossypii Glover. In particular, compounds IIc-01, IIc-03, IIe-02 and IIf-01 show the equal activities to a commercial pesticide Imidacloprid with their LC50 values are 0.21 mg/L, 0.27 mg/L, 0.12 mg/L and 0.24 mg/L, respectively, and compounds IIc-02 and IIe-05 show 10 times insecticidal activities as much as Imidacloprid with their LC50 values both are 0.02 mg/L. Structure-activity relationship and 3D-QSAR analyses indicate that the introduction of fluorine atom is useful for increasing the insecticidal activity of target compounds.
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Affiliation(s)
- Qinglai Wu
- College of Agriculture, Yangtze University, Jinzhou, China.,Institute of Pesticides, Yangtze University, Jinzhou, China
| | - Fenghai Zhao
- Department of Chemistry, College of Science, China Agricultural University, Beijing, P. R. China
| | - Xiang Zhu
- College of Agriculture, Yangtze University, Jinzhou, China.,Institute of Pesticides, Yangtze University, Jinzhou, China
| | - Ziyuan Zhou
- Department of Chemistry, College of Science, China Agricultural University, Beijing, P. R. China
| | - Dongyan Yang
- Department of Chemistry, College of Science, China Agricultural University, Beijing, P. R. China
| | - Zhihong Xu
- College of Agriculture, Yangtze University, Jinzhou, China.,Institute of Pesticides, Yangtze University, Jinzhou, China
| | - Junkai Li
- College of Agriculture, Yangtze University, Jinzhou, China.,Institute of Pesticides, Yangtze University, Jinzhou, China
| | - Zhaohai Qin
- College of Agriculture, Yangtze University, Jinzhou, China.,Department of Chemistry, College of Science, China Agricultural University, Beijing, P. R. China
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8
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Yan X, Zhao L, Ren Y, Dong Z, Cui D, Chen F. Genome-wide association study revealed that the TaGW8 gene was associated with kernel size in Chinese bread wheat. Sci Rep 2019; 9:2702. [PMID: 30804359 PMCID: PMC6389898 DOI: 10.1038/s41598-019-38570-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 12/17/2018] [Indexed: 11/09/2022] Open
Abstract
Using Wheat 90 K SNP assay, kernel-related traits of Chinese bread wheat were used to perform association mapping in 14 environments by GWAS. Results indicated that 996 and 953 of 4417 and 3172 significant SNPs for kernel length and thousand-kernel weight were located on the chromosome 7B. Haplotype analysis of these SNPs on 7B generated the block containing the predicted TaGW8-B1 gene. TaGW8-B1 gene was further cloned by sequencing in bread wheat and a 276-bp InDel was found in the first intron. TaGW8-B1 without and with the 276-bp InDel were designated as TaGW8-B1a and TaGW8-B1b, respectively. Analysis of agronomic traits indicated that cultivars with TaGW8-B1a possessed significantly wider kernel width, significantly more kernel number per spike, longer kernel length, higher thousand-kernel weight and more spikelet number per spike than cultivars with TaGW8-B1b. Furthermore, cultivars with TaGW8-B1a possessed significantly higher yield than cultivars with TaGW8-B1b. Therefore, TaGW8-B1a was considered as a potentially superior allele. Meanwhile, TaGW8-B1a possessed a significantly higher expression level than TaGW8-B1b in mature seeds by qRT-PCR. It possibly suggested that the high expression of TaGW8-B1 was positively associated with kernel size in bread wheat. Distribution of TaGW8-B1 allele indicated that TaGW8-B1a has been positively selected in Chinese wheat.
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Affiliation(s)
- Xuefang Yan
- Agronomy College/National Key Laboratory of Wheat and Maize Crop Science, Henan Agricultural University, Zhengzhou, 450046, China
| | - Lei Zhao
- Agronomy College/National Key Laboratory of Wheat and Maize Crop Science, Henan Agricultural University, Zhengzhou, 450046, China
| | - Yan Ren
- Agronomy College/National Key Laboratory of Wheat and Maize Crop Science, Henan Agricultural University, Zhengzhou, 450046, China
| | - Zhongdong Dong
- Agronomy College/National Key Laboratory of Wheat and Maize Crop Science, Henan Agricultural University, Zhengzhou, 450046, China
| | - Dangqun Cui
- Agronomy College/National Key Laboratory of Wheat and Maize Crop Science, Henan Agricultural University, Zhengzhou, 450046, China
| | - Feng Chen
- Agronomy College/National Key Laboratory of Wheat and Maize Crop Science, Henan Agricultural University, Zhengzhou, 450046, China.
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9
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Cationic surfactants as antifungal agents. Appl Microbiol Biotechnol 2018; 103:97-112. [PMID: 30374671 DOI: 10.1007/s00253-018-9467-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 10/21/2018] [Indexed: 10/28/2022]
Abstract
Fungi-in being responsible for causing diseases in animals and humans as well as environmental contaminations in health and storage facilities-represent a serious concern to health security. Surfactants are a group of chemical compounds used in a broad spectrum of applications. The recently considered potential employment of cationic surfactants as antifungal or fungistatic agents has become a prominent issue in the development of antifungal strategies, especially if such surface-active agents can be synthesized in an eco-friendly manner. In this review, we describe the antifungal effect and the reported mechanisms of action of several types of cationic surfactants and also include a discussion of the contribution of these surfactants to the inhibition of yeast-based-biofilm formation. Furthermore, the putative mechanism of arginine-based tensioactive compounds as antifungal agents and their applications are also analyzed.
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A Cationic Polymer That Shows High Antifungal Activity against Diverse Human Pathogens. Antimicrob Agents Chemother 2017; 61:AAC.00204-17. [PMID: 28739790 DOI: 10.1128/aac.00204-17] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 07/18/2017] [Indexed: 12/19/2022] Open
Abstract
Invasive fungal diseases are generally difficult to treat and often fatal. The therapeutic agents available to treat fungi are limited, and there is a critical need for new agents to combat these deadly infections. Antifungal compound development has been hindered by the challenge of creating agents that are highly active against fungal pathogens but not toxic to the host. Host defense peptides (HDPs) are produced by eukaryotes as a component of the innate immune response to pathogens and have served as inspiration for the development of many new antibacterial compounds. HDP mimics, however, have largely failed to exhibit potent and selective antifungal activity. Here, we present an HDP-like nylon-3 copolymer that is effective against diverse fungi while displaying only mild to moderate toxicity toward mammalian cells. This polymer is active on its own and in synergy with existing antifungal drugs against multiple species of Candida and Cryptococcus, reaching levels of efficacy comparable to those of the clinical agents amphotericin B and fluconazole in some cases. In addition, the polymer acts synergistically with azoles against different species of Aspergillus, including some azole-resistant strains. These findings indicate that nylon-3 polymers are a promising lead for development of new antifungal therapeutic strategies.
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11
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Aphid-stimulated transcriptional reconfigurations of chlorophyllase-2 gene in maize (Zea mays L.) seedlings. BIOCHEM SYST ECOL 2016. [DOI: 10.1016/j.bse.2016.07.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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12
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Chen BX, Li WY, Gao YT, Chen ZJ, Zhang WN, Liu QJ, Chen Z. Involvement of Polyamine Oxidase-Produced Hydrogen Peroxide during Coleorhiza-Limited Germination of Rice Seeds. FRONTIERS IN PLANT SCIENCE 2016; 7:1219. [PMID: 27570530 PMCID: PMC4981591 DOI: 10.3389/fpls.2016.01219] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Accepted: 08/02/2016] [Indexed: 05/18/2023]
Abstract
Seed germination is a complicated biological process that requires regulated enzymatic and non-enzymatic reactions. The action of polyamine oxidase (PAO) produces hydrogen peroxide (H2O2), which promotes dicot seed germination. However, whether and, if so, how PAOs regulate monocot seed germination via H2O2 production is unclear. Herein, we report that the coleorhiza is the main physical barrier to radicle protrusion during germination of rice seed (a monocot seed) and that it does so in a manner similar to that of dicot seed micropylar endosperm. We found that H2O2 specifically and steadily accumulated in the coleorhizae and radicles of germinating rice seeds and was accompanied by increased PAO activity as the germination percentage increased. These physiological indexes were strongly decreased in number by guazatine, a PAO inhibitor. We also identified 11 PAO homologs (OsPAO1-11) in the rice genome, which could be classified into four subfamilies (I, IIa, IIb, and III). The OsPAO genes in subfamilies I, IIa, and IIb (OsPAO1-7) encode PAOs, whereas those in subfamily III (OsPAO8-11) encode histone lysine-specific demethylases. In silico-characterized expression profiles of OsPAO1-7 and those determined by qPCR revealed that OsPAO5 is markedly upregulated in imbibed seeds compared with dry seeds and that its transcript accumulated to a higher level in embryos than in the endosperm. Moreover, its transcriptional abundance increased gradually during seed germination in water and was inhibited by 5 mM guazatine. Taken together, these results suggest that PAO-generated H2O2 is involved in coleorhiza-limited rice seed germination and that OsPAO5 expression accounts for most PAO expression and activity during rice seed germination. These findings should facilitate further study of PAOs and provide valuable information for functional validation of these proteins during seed germination of monocot cereals.
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