1
|
Mahmoud LM, Killiny N, Dutt M. Physiological and molecular responses of 'Hamlin' sweet orange trees expressing the VvmybA1 gene under cold stress conditions. PLANTA 2024; 260:67. [PMID: 39088064 DOI: 10.1007/s00425-024-04496-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2024] [Accepted: 07/25/2024] [Indexed: 08/02/2024]
Abstract
MAIN CONCLUSION Overexpression of VvmybA1 transcription factor in 'Hamlin' citrus enhances cold tolerance by increasing anthocyanin accumulation. This results in improved ROS scavenging, altered gene expression, and stomatal regulation, highlighting anthocyanins' essential role in citrus cold acclimation. Cold stress is a significant threat to citrus cultivation, impacting tree health and productivity. Anthocyanins are known for their role as pigments and have emerged as key mediators of plant defense mechanisms against environmental stressors. This study investigated the potential of anthocyanin overexpression regulated by grape (Vitis vinifera) VvmybA1 transcription factor to enhance cold stress tolerance in citrus trees. Transgenic 'Hamlin' citrus trees overexpressing VvmybA1 were exposed to a 30-day cold stress period at 4 °C along with the control wild-type trees. Our findings reveal that anthocyanin accumulation significantly influences chlorophyll content and their fluorescence parameters, affecting leaf responses to cold stress. Additionally, we recorded enhanced ROS scavenging capacity and distinct expression patterns of key transcription factors and antioxidant-related genes in the transgenic leaves. Furthermore, VvmybA1 overexpression affected stomatal aperture regulation by moderating ABA biosynthesis, resulting in differential responses in a stomatal opening between transgenic and wild-type trees under cold stress. Transgenic trees exhibited reduced hydrogen peroxide levels, enhanced flavonoids, radical scavenging activity, and altered phytohormonal profiles. These findings highlighted the role of VvmybA1-mediated anthocyanin accumulation in enhancing cold tolerance. The current study also underlines the potential of anthocyanin overexpression as a critical regulator of the cold acclimation process by scavenging ROS in plant tissues.
Collapse
Affiliation(s)
- Lamiaa M Mahmoud
- Department of Horticultural Sciences, Citrus Research and Education Center, University of Florida, Lake Alfred, FL, USA
| | - Nabil Killiny
- Department of Plant Pathology, Citrus Research and Education Center, University of Florida, Lake Alfred, USA
| | - Manjul Dutt
- Department of Horticultural Sciences, Citrus Research and Education Center, University of Florida, Lake Alfred, FL, USA.
- Plant Breeding Graduate Program, University of Florida, Gainesville, FL, USA.
| |
Collapse
|
2
|
Paudel L, Kerr S, Prentis P, Tanurdžić M, Papanicolaou A, Plett JM, Cazzonelli CI. Horticultural innovation by viral-induced gene regulation of carotenogenesis. HORTICULTURE RESEARCH 2022; 9:uhab008. [PMID: 35043183 PMCID: PMC8769041 DOI: 10.1093/hr/uhab008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 08/31/2021] [Accepted: 09/24/2021] [Indexed: 06/14/2023]
Abstract
Multipartite viral vectors provide a simple, inexpensive and effective biotechnological tool to transiently manipulate (i.e. reduce or increase) gene expression in planta and characterise the function of genetic traits. The development of virus-induced gene regulation (VIGR) systems usually involve the targeted silencing or overexpression of genes involved in pigment biosynthesis or degradation in plastids, thereby providing rapid visual assessment of success in establishing RNA- or DNA-based VIGR systems in planta. Carotenoids pigments provide plant tissues with an array of yellow, orange, and pinkish-red colours. VIGR-induced transient manipulation of carotenoid-related gene expression has advanced our understanding of carotenoid biosynthesis, regulation, accumulation and degradation, as well as plastid signalling processes. In this review, we describe mechanisms of VIGR, the importance of carotenoids as visual markers of technology development, and knowledge gained through manipulating carotenogenesis in model plants as well as horticultural crops not always amenable to transgenic approaches. We outline how VIGR can be utilised in plants to fast-track the characterisation of gene function(s), accelerate fruit tree breeding programs, edit genomes, and biofortify plant products enriched in carotenoid micronutrients for horticultural innovation.
Collapse
Affiliation(s)
- Lucky Paudel
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW 2751, Australia
| | - Stephanie Kerr
- Centre for Agriculture and the Bioeconomy (CAB), Queensland University of Technology, 2 George Street, Brisbane City, QLD 4000, Australia
- School of Biology and Environmental Sciences, Faculty of Science,
Queensland University of Technology, 2 George Street, Brisbane, QLD 4000, Australia
| | - Peter Prentis
- Centre for Agriculture and the Bioeconomy (CAB), Queensland University of Technology, 2 George Street, Brisbane City, QLD 4000, Australia
- School of Biology and Environmental Sciences, Faculty of Science,
Queensland University of Technology, 2 George Street, Brisbane, QLD 4000, Australia
| | - Miloš Tanurdžić
- School of Biological Sciences, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Alexie Papanicolaou
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW 2751, Australia
| | - Jonathan M Plett
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW 2751, Australia
| | - Christopher I Cazzonelli
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW 2751, Australia
| |
Collapse
|
3
|
Yu Y, Yu J, Wang Q, Wang J, Zhao G, Wu H, Zhu Y, Chu C, Fang J. Overexpression of the rice ORANGE gene OsOR negatively regulates carotenoid accumulation, leads to higher tiller numbers and decreases stress tolerance in Nipponbare rice. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2021; 310:110962. [PMID: 34315587 DOI: 10.1016/j.plantsci.2021.110962] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 05/22/2021] [Accepted: 06/01/2021] [Indexed: 06/13/2023]
Abstract
The ORANGE (OR) gene has been reported to regulate chromoplast differentiation and enhance carotenoid biosynthesis in many dicotyledonous plants. However, the function of the OR gene in monocotyledons, especially rice, is poorly known. Here, the OR gene from rice, OsOR, was isolated and characterized by generating overexpressing and genome editing mutant lines. The OsOR-overexpressing plants exhibited pleiotropic phenotypes, such as alternating transverse green and white sectors on leaves at the early tillering stage, that were due to changes in thylakoid development and reduced carotenoid content. In addition, the number of tillers significantly increased in OsOR-overexpressing plants but decreased in osor mutant lines, a result similar to that previously reported for the carotenoid isomerase mutant mit3. The expression of the DWARF3 and DWARF53 genes that are involved in the strigolactone signalling pathway were similarly downregulated in OsOR-overexpressing plants but upregulated in osor mutants. Moreover, the OsOR-overexpressing plants exhibited greater sensitivity to salt and cold stress, and had lower total chlorophyll and higher MDA contents. All results suggest that the OsOR gene plays an important role not only in carotenoid accumulation but also in tiller number regulation and in responses to environmental stress in rice.
Collapse
Affiliation(s)
- Yang Yu
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Harbin, China; College of Life Science and Engineering, Shenyang University, Shenyang, China
| | - Jiyang Yu
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Harbin, China; Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, China
| | - Qinglong Wang
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Jing Wang
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Harbin, China; Quality and Safety Institute of Agriculture Products, Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Guangxin Zhao
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Harbin, China; College of Advanced Agricultural Science, University of Chinese Academy of Sciences, Beijing, China
| | - Hongkai Wu
- College of Agriculture and Food Science, Zhejiang A&F University, Hangzhou, China
| | - Yanming Zhu
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, China
| | - Chengcai Chu
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China; College of Advanced Agricultural Science, University of Chinese Academy of Sciences, Beijing, China.
| | - Jun Fang
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Harbin, China; College of Advanced Agricultural Science, University of Chinese Academy of Sciences, Beijing, China.
| |
Collapse
|
4
|
Killiny N, Nehela Y, George J, Rashidi M, Stelinski LL, Lapointe SL. Phytoene desaturase-silenced citrus as a trap crop with multiple cues to attract Diaphorina citri, the vector of Huanglongbing. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2021; 308:110930. [PMID: 34034878 DOI: 10.1016/j.plantsci.2021.110930] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 04/17/2021] [Accepted: 04/24/2021] [Indexed: 05/26/2023]
Abstract
Huanglongbing (HLB) is one of the most destructive diseases in citrus worldwide. Unfortunately, HLB has no cure and management relies on insecticides to reduce populations of the vector, Diaphorina citri Kuwayama (Hemiptera: Liviidae). We propose an attract-and-kill strategy using a trap crop as an alternative to vector control to reduce transmission of the pathogen, 'Candidatus Liberibacter asiaticus'. We evaluated vector response to phytoene desaturase-silenced citrus trees using virus-induced gene silencing technology. Citrus tristeza virus (CTV) was used to produce a phytoene desaturase-silenced citrus (CTV-tPDS) that expresses visual, olfactory, and gustatory cues to attract D. citri. We found that D. citri were more attracted to CTV-tPDS plants with noticeably better fecundity and overall population fitness than on control plants. Moreover, rearing D. citri on CTV-tPDS plants significantly increased their survival probability compared with those reared on control plants. CTV-tPDS plants possessed reduced content of both carotenoid and chlorophyll pigments resulting in a consistent photobleached phenotype on citrus leaves which provided a sufficient close-range visual attractant to stimulate D. citri landing. Additionally, CTV-tPDS plants exhibited an enriched profile of volatile organic compounds (VOCs), which offered adequate olfactory cues to attract psyllid from long-range. Finally, CTV-tPDS plants exhibited an enriched metabolite content of phloem sap and leaves which offered appropriate gustatory cues that influenced probing/feeding behavior. We believe that introducing CTV-tPDS plants (as a trap crop) to D. citri-infested orchards will attract and congregate psyllids to facilitate their removal from the target crop with insecticides or by other means. This new strategy could be deployed relatively quickly and economically to HLB-impacted citrus industries. Moreover, it is an eco-friendly strategy because it should partially reduce the input of chemical insecticides ameliorating the indirect cost of HLB infection.
Collapse
Affiliation(s)
- Nabil Killiny
- Department of Plant Pathology, Citrus Research and Education Center, IFAS, University of Florida, 700 Experiment Station Road, Lake Alfred, FL, 33850, USA.
| | - Yasser Nehela
- Department of Plant Pathology, Citrus Research and Education Center, IFAS, University of Florida, 700 Experiment Station Road, Lake Alfred, FL, 33850, USA; Department of Agricultural Botany, Faculty of Agriculture, Tanta University, 31512 Tanta, Egypt
| | - Justin George
- United States Department of Agriculture, Agricultural Research Service, 2001 South Rock Road, Fort Pierce, FL, 34945, USA; United States Department of Agriculture, Agricultural Research Service, 141 Experiment Station Road, Stoneville, MS, 38776, USA
| | - Mahnaz Rashidi
- Department of Plant Pathology, Citrus Research and Education Center, IFAS, University of Florida, 700 Experiment Station Road, Lake Alfred, FL, 33850, USA
| | - Lukasz L Stelinski
- Department of Entomology and Nematology, Citrus Research and Education Center, IFAS, University of Florida, 700 Experiment Station Road, Lake Alfred, FL, 33850, USA
| | - Stephen L Lapointe
- United States Department of Agriculture, Agricultural Research Service, 2001 South Rock Road, Fort Pierce, FL, 34945, USA
| |
Collapse
|