1
|
Exploring the Effectiveness and Durability of Trans-Kingdom Silencing of Fungal Genes in the Vascular Pathogen Verticillium dahliae. Int J Mol Sci 2022; 23:ijms23052742. [PMID: 35269884 PMCID: PMC8910871 DOI: 10.3390/ijms23052742] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 02/25/2022] [Accepted: 02/26/2022] [Indexed: 02/04/2023] Open
Abstract
Host-induced gene silencing (HIGS) based on trans-kingdom RNA interference (RNAi) has been successfully exploited to engineer host resistance to pests and pathogens, including fungi and oomycetes. However, revealing the mechanisms underlying trans-kingdom RNAi between hosts and pathogens lags behind applications. The effectiveness and durability of trans-kingdom silencing of pathogenic genes are uncharacterized. In this study, using our transgenic 35S-VdH1i cotton plants in which dsVdH1-derived small RNAs (siVdH1) accumulated, small RNA sequencing analysis revealed that siVdH1s exclusively occur within the double-stranded (ds)VdH1 region, and no transitive siRNAs were produced beyond this region in recovered hyphae of Verticillium dahliae (V. dahliae). Accordingly, we found that VdH1 silencing was reduced over time in recovered hyphae cultured in vitro, inferring that once the fungus got rid of the 35S-VdH1i cotton plants would gradually regain their pathogenicity. To explore whether continually exporting dsRNAs/siRNAs from transgenic plants into recipient fungal cells guaranteed the effectiveness and stability of HIGS, we created GFP/RFP double-labeled V. dahliae and transgenic Arabidopsis expressing dsGFP (35S-GFPi plants). Confocal images visually demonstrate the efficient silencing of GFP in V. dahliae that colonized host vascular tissues. Taken together, our results demonstrate that HIGS effectively triggers long-lasting trans-kingdom RNAi during plant vasculature V. dahliae interactions, despite no amplification or transitivity of RNAi being noted in this soil-borne fungal pathogen.
Collapse
|
2
|
Qiao Y, Xia R, Zhai J, Hou Y, Feng L, Zhai Y, Ma W. Small RNAs in Plant Immunity and Virulence of Filamentous Pathogens. ANNUAL REVIEW OF PHYTOPATHOLOGY 2021; 59:265-288. [PMID: 34077241 DOI: 10.1146/annurev-phyto-121520-023514] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Gene silencing guided by small RNAs governs a broad range of cellular processes in eukaryotes. Small RNAs are important components of plant immunity because they contribute to pathogen-triggered transcription reprogramming and directly target pathogen RNAs. Recent research suggests that silencing of pathogen genes by plant small RNAs occurs not only during viral infection but also in nonviral pathogens through a process termed host-induced gene silencing, which involves trans-species small RNA trafficking. Similarly, small RNAs are also produced by eukaryotic pathogens and regulate virulence. This review summarizes the small RNA pathways in both plants and filamentous pathogens, including fungi and oomycetes, and discusses their role in host-pathogen interactions. We highlight secondarysmall interfering RNAs of plants as regulators of immune receptor gene expression and executors of host-induced gene silencing in invading pathogens. The current status and prospects of trans-species gene silencing at the host-pathogen interface are discussed.
Collapse
Affiliation(s)
- Yongli Qiao
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China;
| | - Rui Xia
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Horticulture, South China Agricultural University, Guangzhou 510640, China
| | - Jixian Zhai
- School of Life Sciences, Institute of Plant and Food Science, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yingnan Hou
- Department of Microbiology and Plant Pathology, University of California, Riverside, California 92521, USA
| | - Li Feng
- School of Life Sciences, Institute of Plant and Food Science, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yi Zhai
- Department of Microbiology and Plant Pathology, University of California, Riverside, California 92521, USA
| | - Wenbo Ma
- Department of Microbiology and Plant Pathology, University of California, Riverside, California 92521, USA
- The Sainsbury Laboratory, Norwich Research Park, Norwich, NR4 7UH, UK;
| |
Collapse
|
3
|
Ouyang SQ, Park G, Ji HM, Borkovich KA. Small RNA Isolation and Library Construction for Expression Profiling of Small RNAs from Neurospora crassa and Fusarium oxysporum and Analysis of Small RNAs in Fusarium oxysporum-Infected Plant Root Tissue. Methods Mol Biol 2021; 2170:199-212. [PMID: 32797460 DOI: 10.1007/978-1-0716-0743-5_14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Due to crucial roles in gene regulation, noncoding small RNAs (sRNAs) of 20-30 nucleotides (nt) have been intensively studied in mammals and plants and are implicated in significant diseases and metabolic disorders. Elucidation of biogenesis mechanisms and functional characterization of sRNAs is often achieved using tools such as separation of small-sized RNA and deep sequencing. Although RNA interference pathways, such as quelling and meiotic silencing, have been well-described in Neurospora crassa, knowledge of sRNAs in other filamentous fungi is still limited compared to other eukaryotes. As a prerequisite for study, isolation and sequence analysis of sRNAs is necessary. We developed a protocol for isolation and library construction of sRNAs of 20-30 nt for deep sequencing in two filamentous fungi, N. crassa and Fusarium oxysporum f.sp. lycopersici. Using 200-300 μg total RNA, sRNA was isolated by size-fractionation and ligated with adapters and amplified by RT-PCR for deep sequencing. Sequence analysis of several cDNA clones showed that the cloned sRNAs were not tRNAs and rRNAs and were fungal genome-specific. In order to validate fungal miRNAs that were imported into the host cell, we developed a straightforward method to isolate protoplasts from tomato roots infected by Fusarium oxysporum f.sp. lycopersici using enzymatic digestion.
Collapse
Affiliation(s)
- Shou-Qiang Ouyang
- College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, China. .,Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China and Key Laboratory of Plant Functional Genomics of the Ministry of Education, Yangzhou University, Yangzhou, China.
| | - Gyungsoon Park
- Department of Electrical and Biological Physics, Plasma Bioscience Research Institute, Kwangwoon University, Seoul, Republic of Korea
| | - Hui-Min Ji
- College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, China
| | - Katherine A Borkovich
- Department of Microbiology and Plant Pathology, Institute for Integrative Genome Biology, University of California, Riverside, CA, USA.
| |
Collapse
|
4
|
Feng H, Xu M, Gao Y, Liang J, Guo F, Guo Y, Huang L. Vm-milR37 contributes to pathogenicity by regulating glutathione peroxidase gene VmGP in Valsa mali. MOLECULAR PLANT PATHOLOGY 2021; 22:243-254. [PMID: 33278058 PMCID: PMC7814965 DOI: 10.1111/mpp.13023] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 10/18/2020] [Accepted: 11/05/2020] [Indexed: 05/22/2023]
Abstract
MicroRNAs play important roles in various biological processes by regulating their corresponding target genes. However, the function and regulatory mechanism of fungal microRNA-like RNAs (milRNAs) are still largely unknown. In this study, a milRNA (Vm-milR37) was isolated and identified from Valsa mali, which causes the most serious disease on the trunk of apple trees in China. Based on the results of deep sequencing and quantitative reverse transcription PCR, Vm-milR37 was found to be expressed in the mycelium, while it was not expressed during the V. mali infection process. Overexpression of Vm-milR37 did not affect vegetative growth, but significantly decreased pathogenicity. Based on degradome sequencing, the target of Vm-milR37 was identified as VmGP, a glutathione peroxidase. The expression of Vm-milR37 and VmGP showed a divergent trend in V. mali-apple interaction samples and Vm-milR37 overexpression transformants. The expression of VmGP could be suppressed significantly by Vm-milR37 when coexpressed in tobacco leaves. Deletion of VmGP showed significantly reduced pathogenicity compared with the wild type. VmGP deletion mutants showed more sensitivity to hydrogen peroxide. Apple leaves inoculated with Vm-milR37 overexpression transformants and VmGP deletion mutant displayed increased accumulation of reactive oxygen species compared with the wild type. Thus, Vm-milR37 plays a critical role in pathogenicity by regulating VmGP, which contributes to the oxidative stress response during V. mali infection. These results provide important evidence to define the roles of milRNAs and their corresponding target genes in pathogenicity.
Collapse
Affiliation(s)
- Hao Feng
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant ProtectionNorthwest A&F UniversityYanglingChina
| | - Ming Xu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant ProtectionNorthwest A&F UniversityYanglingChina
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life SciencesNorthwest A&F UniversityYanglingChina
| | - Yuqi Gao
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant ProtectionNorthwest A&F UniversityYanglingChina
| | - Jiahao Liang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant ProtectionNorthwest A&F UniversityYanglingChina
| | - Feiran Guo
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant ProtectionNorthwest A&F UniversityYanglingChina
| | - Yan Guo
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant ProtectionNorthwest A&F UniversityYanglingChina
| | - Lili Huang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant ProtectionNorthwest A&F UniversityYanglingChina
| |
Collapse
|
5
|
Li Y, Liu X, Yin Z, You Y, Zou Y, Liu M, He Y, Zhang H, Zheng X, Zhang Z, Wang P. MicroRNA-like milR236, regulated by transcription factor MoMsn2, targets histone acetyltransferase MoHat1 to play a role in appressorium formation and virulence of the rice blast fungus Magnaporthe oryzae. Fungal Genet Biol 2020; 137:103349. [PMID: 32006681 DOI: 10.1016/j.fgb.2020.103349] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 01/28/2020] [Indexed: 12/25/2022]
Abstract
MicroRNAs (miRNAs) play important roles in various cellular growth and developmental processes through post-transcriptional gene regulation via mRNA cleavage and degradation and the inhibition of protein translation. To explore if miRNAs play a role in appressoria formation and virulence that are also governed by the regulators of G-protein signaling (RGS) proteins in the rice blast fungus Magnaporthe oryzae, we have compared small RNA (sRNA) production between several ΔMorgs mutant and the wild-type strains. We have identified sRNA236 as a microRNA-like milR236 that targets the encoding sequence of MoHat1, a histone acetyltransferase type B catalytic subunit involved in appressorium function and virulence. We have also found that milR236 overexpression induces delayed appressorium formation and virulence attenuation, similar to those displayed by the ΔMohat1 mutant strain. Moreover, we have shown that the transcription factor MoMsn2 binds to the promoter sequence of milR236 to further suppress MoHAT1 transcription and MoHat1-regulated appressorium formation and virulence. In summary, by identifying a novel regulatory role of sRNA in the blast fungus, our studies reveal a new paradigm in the multifaceted regulatory pathways that govern the appressorium formation and virulence of M. oryzae.
Collapse
Affiliation(s)
- Ying Li
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Xinyu Liu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Ziyi Yin
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Yimei You
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Yibin Zou
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Muxing Liu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Yanglan He
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Haifeng Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Xiaobo Zheng
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Zhengguang Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
| | - Ping Wang
- Departments of Microbiology, Immunology, and Parasitology, and Pediatrics Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| |
Collapse
|
6
|
Rodríguez-Romero J, Marconi M, Ortega-Campayo V, Demuez M, Wilkinson MD, Sesma A. Virulence- and signaling-associated genes display a preference for long 3'UTRs during rice infection and metabolic stress in the rice blast fungus. THE NEW PHYTOLOGIST 2019; 221:399-414. [PMID: 30169888 DOI: 10.1111/nph.15405] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 07/10/2018] [Indexed: 06/08/2023]
Abstract
Generation of mRNA isoforms by alternative polyadenylation (APA) and their involvement in regulation of fungal cellular processes, including virulence, remains elusive. Here, we investigated genome-wide polyadenylation site (PAS) selection in the rice blast fungus to understand how APA regulates pathogenicity. More than half of Magnaporthe oryzae transcripts undergo APA and show novel motifs in their PAS region. Transcripts with shorter 3'UTRs are more stable and abundant in polysomal fractions, suggesting they are being translated more efficiently. Importantly, rice colonization increases the use of distal PASs of pathogenicity genes, especially those participating in signalling pathways like 14-3-3B, whose long 3'UTR is required for infection. Cleavage factor I (CFI) Rbp35 regulates expression and distal PAS selection of virulence and signalling-associated genes, tRNAs and transposable elements, pointing its potential to drive genomic rearrangements and pathogen evolution. We propose a noncanonical PAS selection mechanism for Rbp35 that recognizes UGUAH, unlike humans, without CFI25. Our results showed that APA controls turnover and translation of transcripts involved in fungal growth and environmental adaptation. Furthermore, these data provide useful information for enhancing genome annotations and for cross-species comparisons of PASs and PAS usage within the fungal kingdom and the tree of life.
Collapse
Affiliation(s)
- Julio Rodríguez-Romero
- Centre for Plant Biotechnology and Genomics (CBGP UPM-INIA), Universidad Politécnica de Madrid (UPM) & Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Campus de Montegancedo, 28223 Pozuelo de Alarcón, Madrid, Spain
- Departamento de Biotecnología y Biología Vegetal, UPM, Campus Ciudad Universitaria, 28040, Madrid, Spain
| | - Marco Marconi
- Centre for Plant Biotechnology and Genomics (CBGP UPM-INIA), Universidad Politécnica de Madrid (UPM) & Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Campus de Montegancedo, 28223 Pozuelo de Alarcón, Madrid, Spain
- Departamento de Biotecnología y Biología Vegetal, UPM, Campus Ciudad Universitaria, 28040, Madrid, Spain
| | - Víctor Ortega-Campayo
- Centre for Plant Biotechnology and Genomics (CBGP UPM-INIA), Universidad Politécnica de Madrid (UPM) & Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Campus de Montegancedo, 28223 Pozuelo de Alarcón, Madrid, Spain
- Departamento de Biotecnología y Biología Vegetal, UPM, Campus Ciudad Universitaria, 28040, Madrid, Spain
| | - Marie Demuez
- Centre for Plant Biotechnology and Genomics (CBGP UPM-INIA), Universidad Politécnica de Madrid (UPM) & Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Campus de Montegancedo, 28223 Pozuelo de Alarcón, Madrid, Spain
- Departamento de Biotecnología y Biología Vegetal, UPM, Campus Ciudad Universitaria, 28040, Madrid, Spain
| | - Mark D Wilkinson
- Centre for Plant Biotechnology and Genomics (CBGP UPM-INIA), Universidad Politécnica de Madrid (UPM) & Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Campus de Montegancedo, 28223 Pozuelo de Alarcón, Madrid, Spain
- Departamento de Biotecnología y Biología Vegetal, UPM, Campus Ciudad Universitaria, 28040, Madrid, Spain
| | - Ane Sesma
- Centre for Plant Biotechnology and Genomics (CBGP UPM-INIA), Universidad Politécnica de Madrid (UPM) & Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Campus de Montegancedo, 28223 Pozuelo de Alarcón, Madrid, Spain
- Departamento de Biotecnología y Biología Vegetal, UPM, Campus Ciudad Universitaria, 28040, Madrid, Spain
| |
Collapse
|
7
|
Characterizing Small RNAs in Filamentous Fungi Using the Rice Blast Fungus, Magnaporthe oryzae, as an Example. Methods Mol Biol 2018. [PMID: 30182228 DOI: 10.1007/978-1-4939-8724-5_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
The goal of this chapter is to provide a framework of sequential steps for small RNA (sRNA) analysis in filamentous fungi. Here, we present protocols for (1) comparative analysis of sRNAs in different conditions, (2) comparisons of sRNA libraries to RNAseq data and (3) identification and analysis of methylguanosine-capped and polyadenylated sRNAs (CPA-sRNAs). This species of small RNA is particularly interesting in Magnaporthe oryzae, as they map to transcription start and end sites of protein-coding genes. While we do not provide specific command lines for scripts, we provide a general framework for steps needed to carry out all three types of analyses, including relevant references, websites and free online tools. Screenshots are provided from our own customized interface using M. oryzae as an example, to assist the reader in visualizing many of the steps.
Collapse
|
8
|
Raman V, Simon SA, Demirci F, Nakano M, Meyers BC, Donofrio NM. Small RNA Functions Are Required for Growth and Development of Magnaporthe oryzae. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2017; 30:517-530. [PMID: 28504560 DOI: 10.1094/mpmi-11-16-0236-r] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
RNA interference (RNAi) is conserved in eukaryotic organisms, and it has been well studied in many animal and plant species and some fungal species, yet it is not well studied in fungal plant pathogens. In the rice blast fungus Magnaporthe oryzae, we examined small RNA (sRNA) and their biogenesis in the context of growth and pathogenicity. Through genetic and genomic analyses, we demonstrate that loss of a single gene encoding Dicer, RNA-dependent RNA polymerase, or Argonaute reduces sRNA levels. These three proteins are required for the biogenesis of sRNA-matching genome-wide regions (coding regions, repeats, and intergenic regions). The loss of one Argonaute reduced both sRNA and fungal virulence on barley leaves. Transcriptome analysis of multiple mutants revealed that sRNA play an important role in transcriptional regulation of repeats and intergenic regions in M. oryzae. Together, these data support that M. oryzae sRNA regulate developmental processes including, fungal growth and virulence.
Collapse
Affiliation(s)
- Vidhyavathi Raman
- 1 Department of Plant & Soil Sciences, University of Delaware, Newark 19716, U.S.A.; and
| | - Stacey A Simon
- 1 Department of Plant & Soil Sciences, University of Delaware, Newark 19716, U.S.A.; and
- 2 Delaware Biotechnology Institute, University of Delaware, Newark 19711, U.S.A
| | - Feray Demirci
- 1 Department of Plant & Soil Sciences, University of Delaware, Newark 19716, U.S.A.; and
- 2 Delaware Biotechnology Institute, University of Delaware, Newark 19711, U.S.A
| | - Mayumi Nakano
- 1 Department of Plant & Soil Sciences, University of Delaware, Newark 19716, U.S.A.; and
- 2 Delaware Biotechnology Institute, University of Delaware, Newark 19711, U.S.A
| | - Blake C Meyers
- 1 Department of Plant & Soil Sciences, University of Delaware, Newark 19716, U.S.A.; and
- 2 Delaware Biotechnology Institute, University of Delaware, Newark 19711, U.S.A
| | - Nicole M Donofrio
- 1 Department of Plant & Soil Sciences, University of Delaware, Newark 19716, U.S.A.; and
| |
Collapse
|
9
|
Sesma A. RNA metabolism and regulation of virulence programs in fungi. Semin Cell Dev Biol 2016; 57:120-127. [DOI: 10.1016/j.semcdb.2016.03.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 03/21/2016] [Accepted: 03/23/2016] [Indexed: 01/16/2023]
|
10
|
Genome Sequences of Three Phytopathogenic Species of the Magnaporthaceae Family of Fungi. G3-GENES GENOMES GENETICS 2015; 5:2539-45. [PMID: 26416668 PMCID: PMC4683626 DOI: 10.1534/g3.115.020057] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Magnaporthaceae is a family of ascomycetes that includes three fungi of great economic importance: Magnaporthe oryzae, Gaeumannomyces graminis var. tritici, and Magnaporthe poae. These three fungi cause widespread disease and loss in cereal and grass crops, including rice blast disease (M. oryzae), take-all disease in wheat and other grasses (G. graminis), and summer patch disease in turf grasses (M. poae). Here, we present the finished genome sequence for M. oryzae and draft sequences for M. poae and G. graminis var. tritici. We used multiple technologies to sequence and annotate the genomes of M. oryzae, M. poae, and G. graminis var. tritici. The M. oryzae genome is now finished to seven chromosomes whereas M. poae and G. graminis var. tritici are sequenced to 40.0× and 25.0× coverage respectively. Gene models were developed by the use of multiple computational techniques and further supported by RNAseq data. In addition, we performed preliminary analysis of genome architecture and repetitive element DNA.
Collapse
|
11
|
Khoddami V, Cairns BR. Transcriptome-wide target profiling of RNA cytosine methyltransferases using the mechanism-based enrichment procedure Aza-IP. Nat Protoc 2014; 9:337-61. [PMID: 24434802 DOI: 10.1038/nprot.2014.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Cytosine methylation within RNA is common, but its full scope and functions are poorly understood, as the RNA targets of most mammalian cytosine RNA methyltransferases (m(5)C-RMTs) remain uncharacterized. To enable their characterization, we developed a mechanism-based method for transcriptome-wide m(5)C-RMT target profiling. All characterized mammalian m(5)C-RMTs form a reversible covalent intermediate with their cytosine substrate-a covalent linkage that is trapped when conducted on the cytosine analog 5-azacytidine (5-aza-C). We used this property to develop Aza-immunoprecipitation (Aza-IP), a methodology to form stable m(5)C-RMT-RNA linkages in cell culture, followed by IP and high-throughput sequencing, to identify direct RNA substrates of m(5)C-RMTs. Remarkably, a cytosine-to-guanine (C→G) transversion occurs specifically at target cytosines, allowing the simultaneous identification of the precise target cytosine within each RNA. Thus, Aza-IP reports only direct RNA substrates and the C→G transversion provides an important criterion for target cytosine identification, which is not available in alternative approaches. Here we present a step-by-step protocol for Aza-IP and downstream analysis, designed to reveal identification of substrate RNAs and precise cytosine targets of m(5)C-RMTs. The entire protocol takes 40-50 d to complete.
Collapse
Affiliation(s)
- Vahid Khoddami
- Howard Hughes Medical Institute (HHMI), Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Bradley R Cairns
- Howard Hughes Medical Institute (HHMI), Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, USA
| |
Collapse
|
12
|
Raman V, Simon SA, Romag A, Demirci F, Mathioni SM, Zhai J, Meyers BC, Donofrio NM. Physiological stressors and invasive plant infections alter the small RNA transcriptome of the rice blast fungus, Magnaporthe oryzae. BMC Genomics 2013; 14:326. [PMID: 23663523 PMCID: PMC3658920 DOI: 10.1186/1471-2164-14-326] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Accepted: 05/02/2013] [Indexed: 11/21/2022] Open
Abstract
Background The rice blast fungus, Magnaporthe oryzae is a destructive pathogen of rice and other related crops, causing significant yield losses worldwide. Endogenous small RNAs (sRNAs), including small interfering RNAs (siRNAs) and microRNAs (miRNAs) are critical components of gene regulation in many eukaryotic organisms. Recently several new species of sRNAs have been identified in fungi. This fact along with the availability of genome sequence makes M. oryzae a compelling target for sRNA profiling. We have examined sRNA species and their biosynthetic genes in M. oryzae, and the degree to which these elements regulate fungal stress responses. To this end, we have characterized sRNAs under different physiological stress conditions, which had not yet been examined in this fungus. Results The resulting libraries are composed of more than 37 million total genome matched reads mapping to intergenic regions, coding sequences, retrotransposons, inverted, tandem, and other repeated regions of the genome with more than half of the small RNAs arising from intergenic regions. The 24 nucleotide (nt) size class of sRNAs was predominant. A comparison to transcriptional data of M. oryzae undergoing the same physiological stresses indicates that sRNAs play a role in transcriptional regulation for a small subset of genes. Support for this idea comes from generation and characterization of mutants putatively involved in sRNAs biogenesis; our results indicate that the deletion of Dicer-like genes and an RNA-Dependent RNA Polymerase gene increases the transcriptional regulation of this subset of genes, including one involved in virulence. Conclusions Various physiological stressors and in planta conditions alter the small RNA profile of the rice blast fungus. Characterization of sRNA biosynthetic mutants helps to clarify the role of sRNAs in transcriptional control.
Collapse
Affiliation(s)
- Vidhyavathi Raman
- Department of Plant & Soil Sciences, University of Delaware, Newark, DE 19716, USA
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Papic N, Maxwell CI, Delker DA, Liu S, Heale BSE, Hagedorn CH. RNA-sequencing analysis of 5' capped RNAs identifies many new differentially expressed genes in acute hepatitis C virus infection. Viruses 2012; 4:581-612. [PMID: 22590687 PMCID: PMC3347324 DOI: 10.3390/v4040581] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Revised: 03/31/2012] [Accepted: 04/03/2012] [Indexed: 12/28/2022] Open
Abstract
We describe the first report of RNA sequencing of 5' capped (Pol II) RNAs isolated from acutely hepatitis C virus (HCV) infected Huh 7.5 cells that provides a general approach to identifying differentially expressed annotated and unannotated genes that participate in viral-host interactions. We identified 100, 684, and 1,844 significantly differentially expressed annotated genes in acutely infected proliferative Huh 7.5 cells at 6, 48, and 72 hours, respectively (fold change ≥ 1.5 and Bonferroni adjusted p-values < 0.05). Most of the differentially expressed genes (>80%) and biological pathways (such as adipocytokine, Notch, Hedgehog and NOD-like receptor signaling) were not identified by previous gene array studies. These genes are critical components of host immune, inflammatory and oncogenic pathways and provide new information regarding changes that may benefit the virus or mediate HCV induced pathology. RNAi knockdown studies of newly identified highly upregulated FUT1 and KLHDC7B genes provide evidence that their gene products regulate and facilitate HCV replication in hepatocytes. Our approach also identified novel Pol II unannotated transcripts that were upregulated. Results further identify new pathways that regulate HCV replication in hepatocytes and suggest that our approach will have general applications in studying viral-host interactions in model systems and clinical biospecimens.
Collapse
Affiliation(s)
- Neven Papic
- Department of Medicine, University of Utah, 30 N 1900 E #3C310, Salt Lake City, UT 84132, USA; (N.P.); (C.I.M.); (D.A.D.); (S.L.); (B.S.E.H.)
| | - Christopher I. Maxwell
- Department of Medicine, University of Utah, 30 N 1900 E #3C310, Salt Lake City, UT 84132, USA; (N.P.); (C.I.M.); (D.A.D.); (S.L.); (B.S.E.H.)
- Huntsman Cancer Institute, University of Utah, 30 N 1900 E #3C310, Salt Lake City, UT 84132, USA
| | - Don A. Delker
- Department of Medicine, University of Utah, 30 N 1900 E #3C310, Salt Lake City, UT 84132, USA; (N.P.); (C.I.M.); (D.A.D.); (S.L.); (B.S.E.H.)
| | - Shuanghu Liu
- Department of Medicine, University of Utah, 30 N 1900 E #3C310, Salt Lake City, UT 84132, USA; (N.P.); (C.I.M.); (D.A.D.); (S.L.); (B.S.E.H.)
| | - Bret S. E. Heale
- Department of Medicine, University of Utah, 30 N 1900 E #3C310, Salt Lake City, UT 84132, USA; (N.P.); (C.I.M.); (D.A.D.); (S.L.); (B.S.E.H.)
| | - Curt H. Hagedorn
- Department of Medicine, University of Utah, 30 N 1900 E #3C310, Salt Lake City, UT 84132, USA; (N.P.); (C.I.M.); (D.A.D.); (S.L.); (B.S.E.H.)
- Department of Experimental Pathology, University of Utah, 30 N 1900 E #3C310, Salt Lake City, UT 84132, USA
- Author to whom correspondence should be addressed; ; Tel.: +1-801-587-4619; Fax: +1-801-585-0187
| |
Collapse
|
14
|
Xiao T, Wang Y, Luo H, Liu L, Wei G, Chen X, Sun Y, Chen X, Skogerbø G, Chen R. A differential sequencing-based analysis of the C. elegans noncoding transcriptome. RNA (NEW YORK, N.Y.) 2012; 18:626-639. [PMID: 22345127 PMCID: PMC3312551 DOI: 10.1261/rna.030965.111] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2011] [Accepted: 12/22/2011] [Indexed: 05/31/2023]
Abstract
Noncoding RNAs are increasingly being recognized as important players in eukaryote biology. However, despite major efforts in mapping the Caenorhabditis elegans transcriptome over the last couple of years, nonpolyadenylated and intermediate-size noncoding RNAs (is-ncRNAs) are still incompletely explored. We have combined an enzymatic approach with full-length RNA-Seq of is-ncRNAs in C. elegans. A total of 473 novel is-ncRNAs has been identified, of which a substantial fraction was associated with transcription factor binding sites and developmentally regulated expression patterns. Analysis of sequence and secondary structure permitted classification of more than 200 is-ncRNAs into several known RNA classes, while another 33 is-ncRNAs were identified as belonging to two previously uncharacterized groups of is-ncRNAs. Three of the unclassified is-ncRNAs contain the 5' Alu domain common to SRP RNAs and specifically bound with the SRP9/14 heterodimer in vitro. One of these (inc394) showed 65% sequence identity with the human, neuron-specific BC200 RNA. Structure-based clustering analysis and in vitro binding experiments supported the notion that the nematode stem-bulge RNAs (sbRNAs) are homologs (or functional analogs) of the Y RNAs. Moreover, analysis of the differential libraries showed that some mature snoRNAs undergo secondary 5' cap modification after processing of the primary transcript, thus suggesting the existence of a wider range of functional RNAs arising from processed and modified fragments of primary transcripts.
Collapse
Affiliation(s)
- Tengfei Xiao
- Laboratory of Bioinformatics and Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- Graduate School of the Chinese Academy of Science, Beijing 100080, China
| | - Yunfei Wang
- Laboratory of Bioinformatics and Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Huaxia Luo
- Laboratory of Bioinformatics and Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- Graduate School of the Chinese Academy of Science, Beijing 100080, China
| | - Lihui Liu
- Laboratory of Bioinformatics and Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- Graduate School of the Chinese Academy of Science, Beijing 100080, China
| | - Guifeng Wei
- Laboratory of Bioinformatics and Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- Graduate School of the Chinese Academy of Science, Beijing 100080, China
| | - Xiaowei Chen
- Laboratory of Bioinformatics and Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- Graduate School of the Chinese Academy of Science, Beijing 100080, China
| | - Yu Sun
- Laboratory of Bioinformatics and Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- Graduate School of the Chinese Academy of Science, Beijing 100080, China
| | - Xiaomin Chen
- Laboratory of Bioinformatics and Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Geir Skogerbø
- Laboratory of Bioinformatics and Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Runsheng Chen
- Laboratory of Bioinformatics and Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| |
Collapse
|
15
|
Walia JJ, Falk BW. Fig mosaic virus mRNAs show generation by cap-snatching. Virology 2012; 426:162-6. [PMID: 22356803 DOI: 10.1016/j.virol.2012.01.035] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Revised: 11/09/2011] [Accepted: 01/28/2012] [Indexed: 10/28/2022]
Abstract
Fig mosaic virus (FMV), a member of the newly described genus Emaravirus, has four negative-sense single-stranded genomic RNAs, and each codes for a single protein in the viral complementary RNA (vcRNA). In this study we show that FMV mRNAs for genome segments 2 and 3 contain short (12-18 nucleotides) heterogeneous nucleotide leader sequences at their 5' termini. Furthermore, by using the high affinity cap binding protein eIF4E(K119A), we also determined that a 5' cap is present on a population of the FMV positive-sense RNAs, presumably as a result of cap-snatching. Northern hybridization results showed that the 5' capped RNA3 segments are slightly smaller than the homologous vcRNA3 and are not polyadenylated. These data suggest that FMV generates 5' capped mRNAs via cap-snatching, similar to strategies used by other negative-sense multipartite ssRNA viruses.
Collapse
Affiliation(s)
- Jeewan Jyot Walia
- Department of Plant Pathology, University of California, Davis, CA 95616, USA
| | | |
Collapse
|
16
|
Park G, Borkovich KA. Small RNA isolation and library construction for expression profiling of small RNAs from Neurospora and Fusarium using illumina high-throughput deep sequencing. Methods Mol Biol 2012; 883:155-64. [PMID: 22589132 DOI: 10.1007/978-1-61779-839-9_12] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Due to crucial roles in gene regulation, noncoding small RNAs (smRNAs) of 20-30 nucleotides (nt) have been intensively studied in mammals and plants, and are known to be implicated in significant diseases and metabolic disorders. Elucidation of biogenesis mechanisms and functional characterization of smRNAs are often achieved using tools, such as separation of small-sized RNA and high-throughput sequencing. Although RNA interference pathways such as quelling and meiotic silencing have been well described in Neurospora crassa, knowledge of smRNAs in filamentous fungi is still limited compared to other eukaryotes. As a prerequisite for study, isolation and sequence analysis of smRNAs are necessary. We developed a protocol for isolation and library construction of smRNAs of 20-30 nt for Solexa sequencing in two -filamentous fungi, N. crassa and Fusarium oxysporum f.sp. lycopersici. Using 200-300 μg total RNA, smRNA was isolated by size fractionation, ligated with adapters, and amplified by RT-PCR for Solexa sequencing. Sequence analysis of several cDNA clones showed that the cloned smRNAs were not tRNAs and rRNAs and were fungal genome specific.
Collapse
Affiliation(s)
- Gyungsoon Park
- Plasma Bioscience Research Institute, Kwangwoon University, Wolgaedong, Nowongu, Seoul, Republic of Korea
| | | |
Collapse
|
17
|
Franceschetti M, Bueno E, Wilson RA, Tucker SL, Gómez-Mena C, Calder G, Sesma A. Fungal virulence and development is regulated by alternative pre-mRNA 3'end processing in Magnaporthe oryzae. PLoS Pathog 2011; 7:e1002441. [PMID: 22194688 PMCID: PMC3240610 DOI: 10.1371/journal.ppat.1002441] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Accepted: 11/01/2011] [Indexed: 12/21/2022] Open
Abstract
RNA-binding proteins play a central role in post-transcriptional mechanisms that control gene expression. Identification of novel RNA-binding proteins in fungi is essential to unravel post-transcriptional networks and cellular processes that confer identity to the fungal kingdom. Here, we carried out the functional characterisation of the filamentous fungus-specific RNA-binding protein RBP35 required for full virulence and development in the rice blast fungus. RBP35 contains an N-terminal RNA recognition motif (RRM) and six Arg-Gly-Gly tripeptide repeats. Immunoblots identified two RBP35 protein isoforms that show a steady-state nuclear localisation and bind RNA in vitro. RBP35 coimmunoprecipitates in vivo with Cleavage Factor I (CFI) 25 kDa, a highly conserved protein involved in polyA site recognition and cleavage of pre-mRNAs. Several targets of RBP35 have been identified using transcriptomics including 14-3-3 pre-mRNA, an important integrator of environmental signals. In Magnaporthe oryzae, RBP35 is not essential for viability but regulates the length of 3′UTRs of transcripts with developmental and virulence-associated functions. The Δrbp35 mutant is affected in the TOR (target of rapamycin) signaling pathway showing significant changes in nitrogen metabolism and protein secretion. The lack of clear RBP35 orthologues in yeast, plants and animals indicates that RBP35 is a novel auxiliary protein of the polyadenylation machinery of filamentous fungi. Our data demonstrate that RBP35 is the fungal equivalent of metazoan CFI 68 kDa and suggest the existence of 3′end processing mechanisms exclusive to the fungal kingdom. The rice blast fungus Magnaporthe oryzae is one of the most damaging diseases of cultivated rice worldwide and an emerging disease on wheat, impacting on global food security. We identify a M. oryzae virulence-deficient mutant defective in the production of a RNA-binding protein (called RBP35). Clear orthologues of RBP35 are absent in yeast, plants and metazoans. We find two RBP35 protein isoforms that localise in the nucleus and bind RNA. Notably, we demonstrate that RBP35 interacts in vivo with a highly conserved protein component of the eukaryotic polyadenylation machinery. We show that RBP35 present different diffusional properties in nuclei of distinct fungal structures, and consequently different protein/nucleic acid interactions. Further, we find that RBP35 regulates the length of 3′UTRs of transcripts with developmental and virulence-associated functions. We prove that the Δrbp35 mutant is affected in the TOR (target of rapamycin) signaling pathway showing significant changes in nitrogen metabolism and protein secretion. Nothing it is known about pre-mRNA 3′ end processing in filamentous fungi and our study suggest that their polyadenylation machinery differs from yeast and higher organisms. This study can provide new insights into the evolution of the pre-mRNA maturation and the regulation of gene expression in eukaryotes.
Collapse
Affiliation(s)
| | - Emilio Bueno
- Disease & Stress Biology Department, John Innes Centre, Norwich, United Kingdom
| | - Richard A. Wilson
- Department of Plant Pathology, University of Nebraska, Lincoln, Nebraska, United States of America
| | - Sara L. Tucker
- Disease & Stress Biology Department, John Innes Centre, Norwich, United Kingdom
| | | | - Grant Calder
- Cell & Developmental Biology Department, John Innes Centre, Norwich, United Kingdom
| | - Ane Sesma
- Disease & Stress Biology Department, John Innes Centre, Norwich, United Kingdom
- * E-mail:
| |
Collapse
|
18
|
Nunes CC, Gowda M, Sailsbery J, Xue M, Chen F, Brown DE, Oh Y, Mitchell TK, Dean RA. Diverse and tissue-enriched small RNAs in the plant pathogenic fungus, Magnaporthe oryzae. BMC Genomics 2011; 12:288. [PMID: 21635781 PMCID: PMC3132168 DOI: 10.1186/1471-2164-12-288] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2011] [Accepted: 06/02/2011] [Indexed: 01/16/2023] Open
Abstract
Background Emerging knowledge of the impact of small RNAs as important cellular regulators has prompted an explosion of small transcriptome sequencing projects. Although significant progress has been made towards small RNA discovery and biogenesis in higher eukaryotes and other model organisms, knowledge in simple eukaryotes such as filamentous fungi remains limited. Results Here, we used 454 pyrosequencing to present a detailed analysis of the small RNA transcriptome (~ 15 - 40 nucleotides in length) from mycelia and appressoria tissues of the rice blast fungal pathogen, Magnaporthe oryzae. Small RNAs mapped to numerous nuclear and mitochondrial genomic features including repetitive elements, tRNA loci, rRNAs, protein coding genes, snRNAs and intergenic regions. For most elements, small RNAs mapped primarily to the sense strand with the exception of repetitive elements to which small RNAs mapped in the sense and antisense orientation in near equal proportions. Inspection of the small RNAs revealed a preference for U and suppression of C at position 1, particularly for antisense mapping small RNAs. In the mycelia library, small RNAs of the size 18 - 23 nt were enriched for intergenic regions and repetitive elements. Small RNAs mapping to LTR retrotransposons were classified as LTR retrotransposon-siRNAs (LTR-siRNAs). Conversely, the appressoria library had a greater proportion of 28 - 35 nt small RNAs mapping to tRNA loci, and were classified as tRNA-derived RNA fragments (tRFs). LTR-siRNAs and tRFs were independently validated by 3' RACE PCR and northern blots, respectively. Conclusions Our findings suggest M. oryzae small RNAs differentially accumulate in vegetative and specialized-infection tissues and may play an active role in genome integrity and regulating growth and development.
Collapse
Affiliation(s)
- Cristiano C Nunes
- Fungal Genomics Laboratory, Center for Integrated Fungal Research, Department of Plant Pathology, North Carolina State University, Raleigh, NC 27606, USA
| | | | | | | | | | | | | | | | | |
Collapse
|