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Bascom C. From the archives: oxylipins, trojan horses, and light-dependent mRNA stabilization. THE PLANT CELL 2023; 35:955-957. [PMID: 36529484 PMCID: PMC10015155 DOI: 10.1093/plcell/koac365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 12/13/2022] [Indexed: 06/17/2023]
Affiliation(s)
- Carlisle Bascom
- The Plant Cell, American Society of Plant Biologists, USA
- Department of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093, USA
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Zhang L, Wang D, Zhang L, Fu J, Yan P, Ge S, Li Z, Ahammed GJ, Han W, Li X. Expression and functional analysis of CsA-IPT5 splice variants during shoot branching in Camellia sinensis. FRONTIERS IN PLANT SCIENCE 2022; 13:977086. [PMID: 36072311 PMCID: PMC9444062 DOI: 10.3389/fpls.2022.977086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 08/05/2022] [Indexed: 06/15/2023]
Abstract
Alternative splicing (AS) is a process by which several functional splice variants are generated from the same precursor mRNA. In our recent study, five CsA-IPT5 splice variants with various numbers of ATTTA motifs in the untranslated regions (UTRs) were cloned. Meanwhile, their transient expression, as well as the expression and functional analysis in the two shoot branching processes were studied. Here, we examined how these splice variants regulate the other three important shoot branching processes, including the spring tea development, the distal branching of new shoots, and the shoot branching induced by 2,3,5-triiodobenzoic acid (TIBA) spraying, and thus unraveling the key CsA-IPT5 transcripts which play the most important roles in the shoot branching of tea plants. The results showed that the increased expression of 5' UTR AS3, 3' UTR AS1 and 3' UTR AS2 could contribute to the increased synthesis of tZ/iP-type cytokinins (CKs), thus promoting the spring tea development. Meanwhile, in the TIBA-induced shoot branching or in the distal branching of the new shoots, CsA-IPT5 transcripts regulated the synthesis of CsA-IPT5 protein and CKs through transcriptional regulation of the ratios of its splice variants. Moreover, 3' UTR AS1 and 3' UTR AS2 both play key roles in these two processes. In summary, it is revealed that 3' UTR AS1 and 3' UTR AS2 of CsA-IPT5 might act as the predominant splice variants in shoot branching of the tea plant, and they both can serve as gene resources for tea plant breeding.
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Affiliation(s)
- Liping Zhang
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture and Rural Affairs, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Donghui Wang
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture and Rural Affairs, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Lan Zhang
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture and Rural Affairs, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Jianyu Fu
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture and Rural Affairs, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Peng Yan
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture and Rural Affairs, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Shibei Ge
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture and Rural Affairs, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Zhengzhen Li
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture and Rural Affairs, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Golam Jalal Ahammed
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture and Rural Affairs, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
- College of Horticulture and Plant Protection, Henan University of Science and Technology, Luoyang, China
| | - Wenyan Han
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture and Rural Affairs, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Xin Li
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture and Rural Affairs, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
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Zhang L, Li M, Yan P, Fu J, Zhang L, Li X, Han W. A novel adenylate isopentenyltransferase 5 regulates shoot branching via the ATTTA motif in Camellia sinensis. BMC PLANT BIOLOGY 2021; 21:521. [PMID: 34753426 PMCID: PMC8577036 DOI: 10.1186/s12870-021-03254-5] [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: 03/04/2021] [Accepted: 09/23/2021] [Indexed: 05/27/2023]
Abstract
BACKGROUND Shoot branching is one of the important agronomic traits affecting yields and quality of tea plant (Camellia sinensis). Cytokinins (CTKs) play critical roles in regulating shoot branching. However, whether and how differently alternative splicing (AS) variant of CTKs-related genes can influence shoot branching of tea plant is still not fully elucidated. RESULTS In this study, five AS variants of CTK biosynthetic gene adenylate isopentenyltransferase (CsA-IPT5) with different 3' untranslated region (3' UTR) and 5' UTR from tea plant were cloned and investigated for their regulatory effects. Transient expression assays showed that there were significant negative correlations between CsA-IPT5 protein expression, mRNA expression of CsA-IPT5 AS variants and the number of ATTTA motifs, respectively. Shoot branching processes induced by exogenous 6-BA or pruning were studied, where CsA-IPT5 was demonstrated to regulate protein synthesis of CsA-IPT5, as well as the biosynthesis of trans-zeatin (tZ)- and isopentenyladenine (iP)-CTKs, through transcriptionally changing ratios of its five AS variants in these processes. Furthermore, the 3' UTR AS variant 2 (3AS2) might act as the predominant AS transcript. CONCLUSIONS Together, our results indicate that 3AS2 of the CsA-IPT5 gene is potential in regulating shoot branching of tea plant and provides a gene resource for improving the plant-type of woody plants.
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Affiliation(s)
- Liping Zhang
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, No. 9 Meiling South Road, Xihu District, Hangzhou, 310008 Zhejiang China
| | - Menghan Li
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, No. 9 Meiling South Road, Xihu District, Hangzhou, 310008 Zhejiang China
| | - Peng Yan
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, No. 9 Meiling South Road, Xihu District, Hangzhou, 310008 Zhejiang China
| | - Jianyu Fu
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, No. 9 Meiling South Road, Xihu District, Hangzhou, 310008 Zhejiang China
| | - Lan Zhang
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, No. 9 Meiling South Road, Xihu District, Hangzhou, 310008 Zhejiang China
| | - Xin Li
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, No. 9 Meiling South Road, Xihu District, Hangzhou, 310008 Zhejiang China
| | - Wenyan Han
- Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, No. 9 Meiling South Road, Xihu District, Hangzhou, 310008 Zhejiang China
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Hua Y, Zhang D, Zhou T, He M, Ding G, Shi L, Xu F. Transcriptomics-assisted quantitative trait locus fine mapping for the rapid identification of a nodulin 26-like intrinsic protein gene regulating boron efficiency in allotetraploid rapeseed. PLANT, CELL & ENVIRONMENT 2016; 39:1601-18. [PMID: 26934080 DOI: 10.1111/pce.12731] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 02/17/2016] [Accepted: 02/23/2016] [Indexed: 05/03/2023]
Abstract
Allotetraploid rapeseed (Brassica napus L., An An Cn Cn , 2n = 4x = 38) is extraordinarily susceptible to boron (B) deficiency, a ubiquitous problem causing severe losses in seed yield. The breeding of B-efficient rapeseed germ plasm is a cost-effective and environmentally friendly strategy for the agricultural industry; however, genes regulating B efficiency in allotetraploid rapeseed have not yet been isolated. In this research, quantitative trait locus (QTL) fine mapping and digital gene expression (DGE) profiling were combined to identify the candidate genes underlying the major-effect QTL qBEC-A3a, which regulates B efficiency. Comparative phenotype analyses of the near-isogenic lines (NILs) indicated that qBEC-A3a plays a significant role in improving B efficiency under B deficiency. Exploiting QTL fine mapping and DGE analyses revealed a nodulin 26-like intrinsic protein (NIP) gene, which encodes a likely boric acid channel. The gene co-expression network for putative B transporters also highlighted its central role in the efficiency of B uptake. An integration of whole-genome re-sequencing (WGS) with bulked segregant analysis (BSA) authenticated the emerging availability of QTL-seq for the QTL analyses in allotetraploid rapeseed. Transcriptomics-assisted QTL mapping and comparative genomics provided novel insights into the rapid identification of quantitative trait genes (QTGs) in plant species with complex genomes.
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Affiliation(s)
- Yingpeng Hua
- National Key Laboratory of Crop Genetic Improvement, Microelement Research Centre, Huazhong Agricultural University, Wuhan, 430070, China
| | - Didi Zhang
- National Key Laboratory of Crop Genetic Improvement, Microelement Research Centre, Huazhong Agricultural University, Wuhan, 430070, China
| | - Ting Zhou
- National Key Laboratory of Crop Genetic Improvement, Microelement Research Centre, Huazhong Agricultural University, Wuhan, 430070, China
| | - Mingliang He
- National Key Laboratory of Crop Genetic Improvement, Microelement Research Centre, Huazhong Agricultural University, Wuhan, 430070, China
| | - Guangda Ding
- National Key Laboratory of Crop Genetic Improvement, Microelement Research Centre, Huazhong Agricultural University, Wuhan, 430070, China
| | - Lei Shi
- National Key Laboratory of Crop Genetic Improvement, Microelement Research Centre, Huazhong Agricultural University, Wuhan, 430070, China
| | - Fangsen Xu
- National Key Laboratory of Crop Genetic Improvement, Microelement Research Centre, Huazhong Agricultural University, Wuhan, 430070, China
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Ger MJ, Louh GY, Lin YH, Feng TY, Huang HE. Ectopically expressed sweet pepper ferredoxin PFLP enhances disease resistance to Pectobacterium carotovorum subsp. carotovorum affected by harpin and protease-mediated hypersensitive response in Arabidopsis. MOLECULAR PLANT PATHOLOGY 2014; 15:892-906. [PMID: 24796566 PMCID: PMC6638834 DOI: 10.1111/mpp.12150] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Plant ferredoxin-like protein (PFLP) is a photosynthesis-type ferredoxin (Fd) found in sweet pepper. It contains an iron-sulphur cluster that receives and delivers electrons between enzymes involved in many fundamental metabolic processes. It has been demonstrated that transgenic plants overexpressing PFLP show a high resistance to many bacterial pathogens, although the mechanism remains unclear. In this investigation, the PFLP gene was transferred into Arabidopsis and its defective derivatives, such as npr1 (nonexpresser of pathogenesis-related gene 1) and eds1 (enhanced disease susceptibility 1) mutants and NAHG-transgenic plants. These transgenic plants were then infected with the soft-rot bacterial pathogen Pectobacterium carotovorum subsp. carotovorum (Erwinia carotovora ssp. carotovora, ECC) to investigate the mechanism behind PFLP-mediated resistance. The results revealed that, instead of showing soft-rot symptoms, ECC activated hypersensitive response (HR)-associated events, such as the accumulation of hydrogen peroxide (H2 O2 ), electrical conductivity leakage and expression of the HR marker genes (ATHSR2 and ATHSR3) in PFLP-transgenic Arabidopsis. This PFLP-mediated resistance could be abolished by inhibitors, such as diphenylene iodonium (DPI), 1-l-trans-epoxysuccinyl-leucylamido-(4-guanidino)-butane (E64) and benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD-fmk), but not by myriocin and fumonisin. The PFLP-transgenic plants were resistant to ECC, but not to its harpin mutant strain ECCAC5082. In the npr1 mutant and NAHG-transgenic Arabidopsis, but not in the eds1 mutant, overexpression of the PFLP gene increased resistance to ECC. Based on these results, we suggest that transgenic Arabidopsis contains high levels of ectopic PFLP; this may lead to the recognition of the harpin and to the activation of the HR and other resistance mechanisms, and is dependent on the protease-mediated pathway.
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Affiliation(s)
- Mang-Jye Ger
- Department of Life Science, National University of Kaohsiung, Kaohsiung, 811, Taiwan
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Aibara I, Miwa K. Strategies for Optimization of Mineral Nutrient Transport in Plants: Multilevel Regulation of Nutrient-Dependent Dynamics of Root Architecture and Transporter Activity. ACTA ACUST UNITED AC 2014; 55:2027-36. [DOI: 10.1093/pcp/pcu156] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Puckette M, Iyer NJ, Tang Y, Dai XB, Zhao P, Mahalingam R. Differential mRNA translation in Medicago truncatula accessions with contrasting responses to ozone-induced oxidative stress. MOLECULAR PLANT 2012; 5:187-204. [PMID: 21873294 DOI: 10.1093/mp/ssr069] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Acute ozone is a model abiotic elicitor of oxidative stress and a useful tool for understanding biochemical and molecular events during oxidative signaling. Two Medicago truncatula accessions with contrasting responses to ozone were used to examine translational regulation during ozone stress. In ozone-resistant JE154, significant reduction in ribosome loading was observed within one hour of ozone treatment, suggesting energy homeostasis as a vital factor for oxidative stress management. Polysomal RNA-based expression profiling with Affymetrix arrays revealed extensive changes in the translatomes of both accessions. Messenger RNAs with low GC content in their 5' and 3'-UTRs were preferentially associated with polysomes during oxidative stress. Genebins analysis revealed extensive changes in various gene ontologies in both accessions. Extensive changes in nicotinate and nicotinamide metabolism genes were corroborated with increased levels of NAD(+) and NADH in JE154. The significantly lower NAD(+):NADH redox status in JE154, in conjunction with higher ATP amounts, provided a cellular milieu conducive for overcoming oxidative stress. Low levels of ATP, NADH, and suppression of antioxidant defense responses, abet build-up of ozone-derived ROS and ultimately lead to oxidative cell death in Jemalong.
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Affiliation(s)
- Michael Puckette
- 246 Noble Research Center, Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA
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Tanaka M, Takano J, Chiba Y, Lombardo F, Ogasawara Y, Onouchi H, Naito S, Fujiwara T. Boron-dependent degradation of NIP5;1 mRNA for acclimation to excess boron conditions in Arabidopsis. THE PLANT CELL 2011; 23:3547-59. [PMID: 21908722 PMCID: PMC3203445 DOI: 10.1105/tpc.111.088351] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Revised: 08/05/2011] [Accepted: 08/24/2011] [Indexed: 05/02/2023]
Abstract
Boron (B) is an essential plant micronutrient that is toxic at higher levels. NIP5;1 is a boric acid channel required for B uptake and growth under B deficiency. Accumulation of the NIP5;1 transcript is upregulated under B deficiency in Arabidopsis thaliana roots. To elucidate the mechanism of regulation, the 5' untranslated region (UTR) of NIP5;1 was tested for its ability to confer B-dependent regulation using β-glucuronidase and green fluorescent protein as reporters. This analysis showed that the 5' UTR was involved in NIP5;1 transcript accumulation in response to B conditions. We also found that high-B conditions trigger NIP5;1 mRNA degradation and that the sequence from +182 to +200 bp in the 5' UTR is required for this mRNA destabilization. In the nip5;1-1 mutant background, a NIP5;1 complementation construct without the 5' UTR produced high levels of mRNA accumulation, increased B concentrations in tissues, and reduced growth under high-B conditions. These data suggest that the 5' UTR controls B-dependent NIP5;1 mRNA degradation and that NIP5;1 mRNA degradation is important for plant acclimation to high-B conditions.
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Affiliation(s)
- Mayuki Tanaka
- Graduate School of Agricultural and Life Science, University of Tokyo, Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Junpei Takano
- Division of Applied Bioscience, Graduate School of Agriculture, Hokkaido University, Sapporo 060-8589, Japan
| | - Yukako Chiba
- Creative Research Initiative, Hokkaido University, Sapporo 001-0021, Japan
- Division of Life Science, Graduate School of Life Science, Hokkaido University, Sapporo 060-8589, Japan
| | - Fabien Lombardo
- Graduate School of Agricultural and Life Science, University of Tokyo, Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Yuki Ogasawara
- Graduate School of Agricultural and Life Science, University of Tokyo, Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Hitoshi Onouchi
- Division of Applied Bioscience, Graduate School of Agriculture, Hokkaido University, Sapporo 060-8589, Japan
- Core Research for Evolutional Science and Technology, Japanese Science and Technology Agency, Kawaguchi 332-0012, Japan
| | - Satoshi Naito
- Division of Applied Bioscience, Graduate School of Agriculture, Hokkaido University, Sapporo 060-8589, Japan
- Division of Life Science, Graduate School of Life Science, Hokkaido University, Sapporo 060-8589, Japan
| | - Toru Fujiwara
- Graduate School of Agricultural and Life Science, University of Tokyo, Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
- Division of Life Science, Graduate School of Life Science, Hokkaido University, Sapporo 060-8589, Japan
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Hensel G, Himmelbach A, Chen W, Douchkov DK, Kumlehn J. Transgene expression systems in the Triticeae cereals. JOURNAL OF PLANT PHYSIOLOGY 2011; 168:30-44. [PMID: 20739094 DOI: 10.1016/j.jplph.2010.07.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2010] [Revised: 07/19/2010] [Accepted: 07/21/2010] [Indexed: 05/29/2023]
Abstract
The control of transgene expression is vital both for the elucidation of gene function and for the engineering of transgenic crops. Given the dominance of the Triticeae cereals in the agricultural economy of the temperate world, the development of well-performing transgene expression systems of known functionality is of primary importance. Transgenes can be expressed either transiently or stably. Transient expression systems based on direct or virus-mediated gene transfer are particularly useful in situations where the need is to rapidly screen large numbers of genes. However, an unequivocal understanding of gene function generally requires that a transgene functions throughout the plant's life and is transmitted through the sexual cycle, since this alone allows its effect to be decoupled from the plant's response to the generally stressful gene transfer event. Temporal, spatial and quantitative control of a transgene's expression depends on its regulatory environment, which includes both its promoter and certain associated untranslated region sequences. While many transgenic approaches aim to manipulate plant phenotype via ectopic gene expression, a transgene sequence can be also configured to down-regulate the expression of its endogenous counterpart, a strategy which exploits the natural gene silencing machinery of plants. In this review, current technical opportunities for controlling transgene expression in the Triticeae species are described. Apart from protocols for transient and stable gene transfer, the choice of promoters and other untranslated regulatory elements, we also consider signal peptides, as they too govern the abundance and particularly the sub-cellular localization of transgene products.
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Affiliation(s)
- Götz Hensel
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Corrensstrasse 3, Gatersleben, Germany
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Abstract
Proper degradation of plant messenger RNA is crucial for the maintenance of cellular and organismal homeostasis, and it must be properly regulated to enable rapid adjustments in response to endogenous and external cues. Only a few dedicated studies have been done so far to address the fundamental mechanisms of mRNA decay in plants, especially as compared with fungal and mammalian model systems. Consequently, our systems-level understanding of plant mRNA decay remains fairly rudimentary. Nevertheless, a number of serendipitous findings in recent years have reasserted the central position of the regulated mRNA decay in plant physiology. In addition, the meteoric rise to prominence of the plant small RNA field has spawned a renewed interest in the general plant mRNA turnover pathways. Combined with the advent of widely accessible microarray platforms, these advances allow for a renewed hope of rapid progress in our understanding of the fundamental rules governing regulated mRNA degradation in plants. This chapter summarizes recent findings in this field.
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Affiliation(s)
- D A Belostotsky
- School of Biological Sciences, University of Missouri-Kansas City, Kansas City, MO 64110, USA.
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Yakir E, Hilman D, Hassidim M, Green RM. CIRCADIAN CLOCK ASSOCIATED1 transcript stability and the entrainment of the circadian clock in Arabidopsis. PLANT PHYSIOLOGY 2007; 145:925-32. [PMID: 17873091 PMCID: PMC2048808 DOI: 10.1104/pp.107.103812] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The circadian clock is an endogenous mechanism that generates rhythms with an approximately 24-h period and enables plants to predict and adapt to daily and seasonal changes in their environment. These rhythms are generated by molecular oscillators that in Arabidopsis (Arabidopsis thaliana) have been shown to consist of interlocking feedback loops involving a number of elements. An important characteristic of circadian oscillators is that they can be entrained by daily environmental changes in light and temperature. Previous work has shown that one possible entrainment point for the Arabidopsis oscillator is the light-mediated regulation of expression of one of the oscillator genes, CIRCADIAN CLOCK ASSOCIATED1 (CCA1). In this article, we have used transgenic plants with constitutive CCA1 expression to show that light also regulates CCA1 transcript stability. Our experiments show that CCA1 messenger RNA is relatively stable in the dark and in far-red light but has a short half-life in red and blue light. Furthermore, using transgenic plants expressing chimeric CCA1 constructs, we demonstrate that the instability determinants in CCA1 transcripts are probably located in the coding region. We suggest that the combination of light regulation of CCA1 transcription and CCA1 messenger RNA degradation is important for ensuring that the Arabidopsis circadian oscillator is accurately entrained by environmental changes.
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Affiliation(s)
- Esther Yakir
- Department of Plant and Environmental Sciences, Institute for Life Sciences, Hebrew University, Givat Ram, Jerusalem 91904, Israel
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Mathur S, Dasgupta I. Downstream promoter sequence of an Indian isolate of Rice tungro bacilliform virus alters tissue-specific expression in host rice and acts differentially in heterologous system. PLANT MOLECULAR BIOLOGY 2007; 65:259-75. [PMID: 17721744 DOI: 10.1007/s11103-007-9214-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2007] [Accepted: 07/20/2007] [Indexed: 05/16/2023]
Abstract
An Indian isolate of Rice tungro bacilliform virus from West Bengal (RTBV-WB) showed significant nucleotide differences in its putative promoter region when compared with a previously characterized isolate from Philippines. The transcription start site of RTBV-WB was mapped followed by assessing the activity and tissue-specificity of the full-length (FL) promoter (-231 to +645) and several of its upstream and downstream deletions by studying the expression of beta-Glucuronidase (GUS) reporter gene in transgenic rice (Oryza sativa L. subsp. indica) plants at various stages of development. In addition to the expected vascular-specific expression pattern, studied by histochemical staining, GUS enzymatic assay and northern and RT-PCR analysis, two novel patterns were revealed in some of the downstream deleted versions; a non-expressing type, representing no expression at any stage in any tissue and constitutive type, representing constitutive expression at all stages in most tissues. This indicated the presence of previously unreported positive and negative cis-regulatory elements in the downstream region. The negative element and a putative enhancer region in the upstream region specifically bound to rice nuclear proteins in vitro. The FL and its deletion derivatives were also active in heterologous systems like tobacco (Nicotiana tabacum) and wheat (Triticum durum). Expression patterns in tobacco were different from those observed in rice suggesting the importance of upstream elements in those systems and host-specific regulation of the promoter in diverse organisms. Thus, the RTBV-WB FL promoter and its derivatives contain an array of cis-elements, which control constitutive or tissue- and development-specific gene expression in a combinatorial fashion.
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Affiliation(s)
- Saloni Mathur
- Department of Plant Molecular Biology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
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Huang HE, Liu CA, Lee MJ, Kuo CG, Chen HM, Ger MJ, Tsai YC, Chen YR, Lin MK, Feng TY. Resistance enhancement of transgenic tomato to bacterial pathogens by the heterologous expression of sweet pepper ferredoxin-I protein. PHYTOPATHOLOGY 2007; 97:900-906. [PMID: 18943629 DOI: 10.1094/phyto-97-8-0900] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
ABSTRACT Expression of a foreign gene to enhance plant disease resistance to bacterial pathogens is a favorable strategy. It has been demonstrated that expressing sweet pepper ferredoxin-I protein (PFLP) in transgenic plants can enhance disease resistance to bacterial pathogens that infect leaf tissue. In this study, PFLP was applied to protect tomato (Lycopersicon esculentum cv. cherry Cln1558a) from the root-infecting pathogen, Ralstonia solanacearum. Independent R. solanacearum resistant T(1) lines were selected and bred to produce homozygous T(2) generations. Selected T(2) transgenic lines 24-18-7 and 26-2-1a, which showed high expression levels of PFLP in root tissue, were resistant to disease caused by R. solanacearum. In contrast, the transgenic line 23-17-1b and nontransgenic tomato, which showed low expression levels of PFLP in root tissue, were not resistant to R. solanacearum infection. The expansion of R. solanacearum populations in stem tissue of transgenic tomato line 24-18-7 was limited compared with the nontransgenic tomato Cln1558a. Using a detached leaf assay, transgenic line 24-18-7 was also resistant to maceration caused by E. carotovora subsp. carotovora; however, resistance to E. carotovora subsp. carotovora was less apparent in transgenic lines 26-2-1a and 23-17-1b. These results demonstrate that PFLP is able to enhance disease resistance at different levels to bacterial pathogens in individual tissue of transgenic tomato.
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