1
|
Kreida S, Narita A, Johnson MD, Tocheva EI, Das A, Ghosal D, Jensen GJ. Cryo-EM structure of the Agrobacterium tumefaciens T4SS-associated T-pilus reveals stoichiometric protein-phospholipid assembly. Structure 2023; 31:385-394.e4. [PMID: 36870333 PMCID: PMC10168017 DOI: 10.1016/j.str.2023.02.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 01/08/2023] [Accepted: 02/07/2023] [Indexed: 03/06/2023]
Abstract
Agrobacterium tumefaciens causes crown gall disease in plants by the horizontal transfer of oncogenic DNA. The conjugation is mediated by the VirB/D4 type 4 secretion system (T4SS) that assembles an extracellular filament, the T-pilus, and is involved in mating pair formation between A. tumefaciens and the recipient plant cell. Here, we present a 3 Å cryoelectron microscopy (cryo-EM) structure of the T-pilus solved by helical reconstruction. Our structure reveals that the T-pilus is a stoichiometric assembly of the VirB2 major pilin and phosphatidylglycerol (PG) phospholipid with 5-start helical symmetry. We show that PG head groups and the positively charged Arg 91 residues of VirB2 protomers form extensive electrostatic interactions in the lumen of the T-pilus. Mutagenesis of Arg 91 abolished pilus formation. While our T-pilus structure is architecturally similar to previously published conjugative pili structures, the T-pilus lumen is narrower and positively charged, raising questions of whether the T-pilus is a conduit for ssDNA transfer.
Collapse
Affiliation(s)
- Stefan Kreida
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA; Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, 171 77 Stockholm, Sweden
| | - Akihiro Narita
- Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
| | - Matthew D Johnson
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Elitza I Tocheva
- Department of Microbiology and Immunology, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, Canada
| | - Anath Das
- Department of Biochemistry, Molecular Biology and Biophysics, and Microbial and Plant Genomics Institute, University of Minnesota, Minneapolis, MN 55455, USA
| | - Debnath Ghosal
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, Australia; ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, Australia.
| | - Grant J Jensen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA; Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84604, USA.
| |
Collapse
|
2
|
Hooykaas PJJ. The Ti Plasmid, Driver of Agrobacterium Pathogenesis. PHYTOPATHOLOGY 2023; 113:594-604. [PMID: 37098885 DOI: 10.1094/phyto-11-22-0432-ia] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The phytopathogenic bacterium Agrobacterium tumefaciens causes crown gall disease in plants, characterized by the formation of tumor-like galls where wounds were present. Nowadays, however, the bacterium and its Ti (tumor-inducing) plasmid is better known as an effective vector for the genetic manipulation of plants and fungi. In this review, I will briefly summarize some of the major discoveries that have led to this bacterium now playing such a prominent role worldwide in plant and fungal research at universities and research institutes and in agricultural biotechnology for the production of genetically modified crops. I will then delve a little deeper into some aspects of Agrobacterium biology and discuss the diversity among agrobacteria and the taxonomic position of these bacteria, the diversity in Ti plasmids, the molecular mechanism used by the bacteria to transform plants, and the discovery of protein translocation from the bacteria to host cells as an essential feature of Agrobacterium-mediated transformation.
Collapse
|
3
|
Lacroix B, Citovsky V. Genetic factors governing bacterial virulence and host plant susceptibility during Agrobacterium infection. ADVANCES IN GENETICS 2022; 110:1-29. [PMID: 37283660 PMCID: PMC10241481 DOI: 10.1016/bs.adgen.2022.08.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Several species of the Agrobacterium genus represent unique bacterial pathogens able to genetically transform plants, by transferring and integrating a segment of their own DNA (T-DNA, transferred DNA) in their host genome. Whereas in nature this process results in uncontrolled growth of the infected plant cells (tumors), this capability of Agrobacterium has been widely used as a crucial tool to generate transgenic plants, for research and biotechnology. The virulence of Agrobacterium relies on a series of virulence genes, mostly encoded on a large plasmid (Ti-plasmid, tumor inducing plasmid), involved in the different steps of the DNA transfer to the host cell genome: activation of bacterial virulence, synthesis and export of the T-DNA and its associated proteins, intracellular trafficking of the T-DNA and effector proteins in the host cell, and integration of the T-DNA in the host genomic DNA. Multiple interactions between these bacterial encoded proteins and host factors occur during the infection process, which determine the outcome of the infection. Here, we review our current knowledge of the mechanisms by which bacterial and plant factors control Agrobacterium virulence and host plant susceptibility.
Collapse
|
4
|
DNA Double-Strand Break Repairs and Their Application in Plant DNA Integration. Genes (Basel) 2022; 13:genes13020322. [PMID: 35205367 PMCID: PMC8871565 DOI: 10.3390/genes13020322] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/07/2022] [Accepted: 02/07/2022] [Indexed: 01/25/2023] Open
Abstract
Double-strand breaks (DSBs) are considered to be one of the most harmful and mutagenic forms of DNA damage. They are highly toxic if unrepaired, and can cause genome rearrangements and even cell death. Cells employ two major pathways to repair DSBs: homologous recombination (HR) and non-homologous end-joining (NHEJ). In plants, most applications of genome modification techniques depend on the development of DSB repair pathways, such as Agrobacterium-mediated transformation (AMT) and gene targeting (GT). In this paper, we review the achieved knowledge and recent advances on the DNA DSB response and its main repair pathways; discuss how these pathways affect Agrobacterium-mediated T-DNA integration and gene targeting in plants; and describe promising strategies for producing DSBs artificially, at definite sites in the genome.
Collapse
|
5
|
Roushan MR, Shao S, Poledri I, Hooykaas PJJ, van Heusden GPH. Increased Agrobacterium-mediated transformation of Saccharomyces cerevisiae after deletion of the yeast ADA2 gene. Lett Appl Microbiol 2021; 74:228-237. [PMID: 34816457 PMCID: PMC9299121 DOI: 10.1111/lam.13605] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 11/04/2021] [Accepted: 11/08/2021] [Indexed: 12/23/2022]
Abstract
Agrobacterium tumefaciens is the causative agent of crown gall disease and is widely used as a vector to create transgenic plants. Under laboratory conditions, the yeast Saccharomyces cerevisiae and other yeasts and fungi can also be transformed, and Agrobacterium-mediated transformation (AMT) is now considered the method of choice for genetic transformation of many fungi. Unlike plants, in S. cerevisiae, T-DNA is integrated preferentially by homologous recombination and integration by non-homologous recombination is very inefficient. Here we report that upon deletion of ADA2, encoding a component of the ADA and SAGA transcriptional adaptor/histone acetyltransferase complexes, the efficiency of AMT significantly increased regardless of whether integration of T-DNA was mediated by homologous or non-homologous recombination. This correlates with an increase in double-strand DNA breaks, the putative entry sites for T-DNA, in the genome of the ada2Δ deletion mutant, as visualized by the number of Rad52-GFP foci. Our observations may be useful to enhance the transformation of species that are difficult to transform.
Collapse
Affiliation(s)
- M R Roushan
- Institute of Biology, Leiden University, Leiden, The Netherlands
| | - S Shao
- Institute of Biology, Leiden University, Leiden, The Netherlands
| | - I Poledri
- Institute of Biology, Leiden University, Leiden, The Netherlands
| | - P J J Hooykaas
- Institute of Biology, Leiden University, Leiden, The Netherlands
| | | |
Collapse
|
6
|
Zou G, Xiao M, Chai S, Zhu Z, Wang Y, Zhou Z. Efficient genome editing in filamentous fungi via an improved CRISPR-Cas9 ribonucleoprotein method facilitated by chemical reagents. Microb Biotechnol 2021; 14:2343-2355. [PMID: 32841542 PMCID: PMC8601184 DOI: 10.1111/1751-7915.13652] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 07/29/2020] [Accepted: 07/29/2020] [Indexed: 12/21/2022] Open
Abstract
DNA double-strand break (DSB) repair induced by the RNA-programmed nuclease Cas9 has become a popular method for genome editing. Direct genome editing via Cas9-CRISPR gRNA (guide RNA) ribonucleoprotein (RNP) complexes assembled in vitro has also been successful in some fungi. However, the efficiency of direct RNP transformation into fungal protoplasts is currently too low. Here, we report an optimized genome editing approach for filamentous fungi based on RNPs facilitated by adding chemical reagents. We increased the transformation efficiency of RNPs significantly by adding Triton X-100 and prolonging the incubation time, and the editing efficiency reached 100% in Trichoderma reesei and Cordyceps militaris. The optimized RNP-based method also achieved efficient (56.52%) homologous recombination integration with short homology arms (20 bp) and gene disruption (7.37%) that excludes any foreign DNA (selection marker) in T. reesei. In particular, after adding reagents related to mitosis and cell division, the further optimized protocol showed an increased ratio of edited homokaryotic transformants (from 0% to 40.0% for inositol and 71.43% for benomyl) from Aspergillus oryzae, which contains multinucleate spores and protoplasts. Furthermore, the multi-target engineering efficiency of the optimized RNP transformation method was similar to those of methods based on in vivo expression of Cas9. This newly established genome editing system based on RNPs may be widely applicable to construction of genome-edited fungi for the food and medical industries, and has good prospects for commercialization.
Collapse
Affiliation(s)
- Gen Zou
- CAS‐Key Laboratory of Synthetic BiologyCAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of ScienceFenglin Rd 300Shanghai200032China
- Shanghai Key Laboratory of Agricultural Genetics and BreedingInstitute of Edible FungiShanghai Academy of Agriculture Science1000 Jinqi Rd, FengxianShanghai201403China
| | - Meili Xiao
- CAS‐Key Laboratory of Synthetic BiologyCAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of ScienceFenglin Rd 300Shanghai200032China
- University of Chinese Academy of SciencesBeijing100049China
| | - Shunxing Chai
- CAS‐Key Laboratory of Synthetic BiologyCAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of ScienceFenglin Rd 300Shanghai200032China
- University of Chinese Academy of SciencesBeijing100049China
| | - Zhihua Zhu
- CAS‐Key Laboratory of Synthetic BiologyCAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of ScienceFenglin Rd 300Shanghai200032China
- University of Chinese Academy of SciencesBeijing100049China
| | - Ying Wang
- Shanghai Key Laboratory of Agricultural Genetics and BreedingInstitute of Edible FungiShanghai Academy of Agriculture Science1000 Jinqi Rd, FengxianShanghai201403China
| | - Zhihua Zhou
- CAS‐Key Laboratory of Synthetic BiologyCAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of ScienceFenglin Rd 300Shanghai200032China
| |
Collapse
|
7
|
Thomy J, Sanchez F, Gut M, Cruz F, Alioto T, Piganeau G, Grimsley N, Yau S. Combining Nanopore and Illumina Sequencing Permits Detailed Analysis of Insertion Mutations and Structural Variations Produced by PEG-Mediated Transformation in Ostreococcus tauri. Cells 2021; 10:cells10030664. [PMID: 33802698 PMCID: PMC8002553 DOI: 10.3390/cells10030664] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/09/2021] [Accepted: 03/15/2021] [Indexed: 12/13/2022] Open
Abstract
Ostreococcus tauri is a simple unicellular green alga representing an ecologically important group of phytoplankton in oceans worldwide. Modern molecular techniques must be developed in order to understand the mechanisms that permit adaptation of microalgae to their environment. We present for the first time in O. tauri a detailed characterization of individual genomic integration events of foreign DNA of plasmid origin after PEG-mediated transformation. Vector integration occurred randomly at a single locus in the genome and mainly as a single copy. Thus, we confirmed the utility of this technique for insertional mutagenesis. While the mechanism of double-stranded DNA repair in the O. tauri model remains to be elucidated, we clearly demonstrate by genome resequencing that the integration of the vector leads to frequent structural variations (deletions/insertions and duplications) and some chromosomal rearrangements in the genome at the insertion loci. Furthermore, we often observed variations in the vector sequence itself. From these observations, we speculate that a nonhomologous end-joining-like mechanism is employed during random insertion events, as described in plants and other freshwater algal models. PEG-mediated transformation is therefore a promising molecular biology tool, not only for functional genomic studies, but also for biotechnological research in this ecologically important marine alga.
Collapse
Affiliation(s)
- Julie Thomy
- Sorbonne Université, CNRS, UMR 7232 Biologie Intégrative des Organismes Marins (BIOM), Observatoire Océanologique, F-66650 Banyuls-sur-Mer, France; (J.T.); (F.S.); (G.P.)
| | - Frederic Sanchez
- Sorbonne Université, CNRS, UMR 7232 Biologie Intégrative des Organismes Marins (BIOM), Observatoire Océanologique, F-66650 Banyuls-sur-Mer, France; (J.T.); (F.S.); (G.P.)
| | - Marta Gut
- CNAG-CRG, Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 4, 08028 Barcelona, Spain; (M.G.); (F.C.); (T.A.)
- Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
| | - Fernando Cruz
- CNAG-CRG, Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 4, 08028 Barcelona, Spain; (M.G.); (F.C.); (T.A.)
| | - Tyler Alioto
- CNAG-CRG, Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 4, 08028 Barcelona, Spain; (M.G.); (F.C.); (T.A.)
- Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
| | - Gwenael Piganeau
- Sorbonne Université, CNRS, UMR 7232 Biologie Intégrative des Organismes Marins (BIOM), Observatoire Océanologique, F-66650 Banyuls-sur-Mer, France; (J.T.); (F.S.); (G.P.)
| | - Nigel Grimsley
- Sorbonne Université, CNRS, UMR 7232 Biologie Intégrative des Organismes Marins (BIOM), Observatoire Océanologique, F-66650 Banyuls-sur-Mer, France; (J.T.); (F.S.); (G.P.)
- Correspondence: (N.G.); (S.Y.)
| | - Sheree Yau
- Sorbonne Université, CNRS, UMR 7232 Biologie Intégrative des Organismes Marins (BIOM), Observatoire Océanologique, F-66650 Banyuls-sur-Mer, France; (J.T.); (F.S.); (G.P.)
- Correspondence: (N.G.); (S.Y.)
| |
Collapse
|
8
|
Tsakraklides V. Targeted Integration Through Transformation of Hydroxyurea-Arrested Cells. Methods Mol Biol 2021; 2307:139-145. [PMID: 33847987 DOI: 10.1007/978-1-0716-1414-3_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
Homologous recombination is required to specifically target DNA to a desired genomic locus. Non-homologous end joining is the predominant form of recombination in Yarrowia lipolytica. Transformation of this organism with linear DNA therefore results in random integration of the introduced DNA into the genome. In this protocol, hydroxyurea-mediated cell cycle arrest is applied to significantly increase the rate of homologous recombination during transformation and enhance targeted integration.
Collapse
|
9
|
An efficient genetic transformation system for Chinese medicine fungus Tolypocladium ophioglossoides. J Microbiol Methods 2020; 176:106032. [PMID: 32805368 DOI: 10.1016/j.mimet.2020.106032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 07/26/2020] [Accepted: 07/29/2020] [Indexed: 11/22/2022]
Abstract
Tolypocladium ophioglossoides is a rare and valuable fungus extensively used in Chinese medicine for relieving postmenopausal syndrome in women yet its bioactive molecules are unknown. To explore its molecular mechanisms, we have developed a reliable Agrobacterium-mediated transformation system using the selective marker: the chlorimuron ethyl-resistance gene sur. For this purpose, we firstly constructed a T-DNA binary vector system and then improved the transformation efficiency by optimizing conditional parameters including the Agrobacterium tumefaciens concentration, the conidia number of T. ophioglossoides, the co-culture time and the concentration of acetosyringone. Furthermore, we have knocked-out the ku70 gene,which is a key gene in non-homologous end joining (NHEJ) DNA repair pathway,and the effect of the length of the homologous arms (HA) on the genetic transformation efficacy was also examined, which increased by 60% when HA was about 3 kb in length. Our results suggest that the genetic transformation system is efficient and feasible for the truffle-parasite fungus T. ophioglossoides, which can further be used in large-scale experiments for characterization of genes of interest in future work.
Collapse
|
10
|
Lichius A, Ruiz DM, Zeilinger S. Genetic Transformation of Filamentous Fungi: Achievements and Challenges. GRAND CHALLENGES IN FUNGAL BIOTECHNOLOGY 2020. [DOI: 10.1007/978-3-030-29541-7_5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
|
11
|
Lacroix B, Citovsky V. Pathways of DNA Transfer to Plants from Agrobacterium tumefaciens and Related Bacterial Species. ANNUAL REVIEW OF PHYTOPATHOLOGY 2019; 57:231-251. [PMID: 31226020 PMCID: PMC6717549 DOI: 10.1146/annurev-phyto-082718-100101] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Genetic transformation of host plants by Agrobacterium tumefaciens and related species represents a unique model for natural horizontal gene transfer. Almost five decades of studying the molecular interactions between Agrobacterium and its host cells have yielded countless fundamental insights into bacterial and plant biology, even though several steps of the DNA transfer process remain poorly understood. Agrobacterium spp. may utilize different pathways for transferring DNA, which likely reflects the very wide host range of Agrobacterium. Furthermore, closely related bacterial species, such as rhizobia, are able to transfer DNA to host plant cells when they are provided with Agrobacterium DNA transfer machinery and T-DNA. Homologs of Agrobacterium virulence genes are found in many bacterial genomes, but only one non-Agrobacterium bacterial strain, Rhizobium etli CFN42, harbors a complete set of virulence genes and can mediate plant genetic transformation when carrying a T-DNA-containing plasmid.
Collapse
Affiliation(s)
- Benoît Lacroix
- Department of Biochemistry and Cell Biology, State University of New York, Stony Brook, New York 11794-5215, USA;
| | - Vitaly Citovsky
- Department of Biochemistry and Cell Biology, State University of New York, Stony Brook, New York 11794-5215, USA;
| |
Collapse
|
12
|
Jiao X, Zhang Y, Liu X, Zhang Q, Zhang S, Zhao ZK. Developing a CRISPR/Cas9 System for Genome Editing in the Basidiomycetous Yeast Rhodosporidium toruloides. Biotechnol J 2019; 14:e1900036. [PMID: 31066204 DOI: 10.1002/biot.201900036] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 04/23/2019] [Indexed: 12/25/2022]
Abstract
The basidiomycetous yeast Rhodosporidium toruloides (R. toruloides) has been explored as a promising host for the production of lipids and carotenoids. However, the rational manipulation of this yeast remains difficult due to lack of efficient genetic tools. Here, the development of a clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated nuclease (Cas9) system for genome editing in R. toruloides is described. First, R. toruloides strains are generated with sufficient production of the Cas9 protein of Staphylococcus aureus origin by integrating a cassette containing a codon-optimized Cas9 gene into the genome. In parallel, two U6 genes are identified, predicting two U6 promoters and confirming better transcription of single-guide RNA (sgRNA) with the U6b promoter. Next, sgRNA cassettes are designed targeting CRTI, CAR2, and CLYBL gene, respectively, transforming into those Cas9-expressed strains, and finding over 60% transformants with successful insertion and deletion (indel) mutations. Furthermore, when the sgRNA cassette includes donor DNA flanked by two homologous arms of the gene CRTI, gene knockout occurs via homologous recombination. Thus, the CRISPR/Cas9 system is now established as a powerful genome-editing tool in R. toruloides, which should facilitate functional genomic study and advanced cell factory development.
Collapse
Affiliation(s)
- Xiang Jiao
- Division of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yue Zhang
- Division of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiangjian Liu
- Division of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Qi Zhang
- Division of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Sufang Zhang
- Division of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Zongbao K Zhao
- Division of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| |
Collapse
|
13
|
Li C, Lin F, Sun W, Yuan S, Zhou Z, Wu FG, Chen Z. Constitutive hyperproduction of sorbicillinoids in Trichoderma reesei ZC121. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:291. [PMID: 30386428 PMCID: PMC6202828 DOI: 10.1186/s13068-018-1296-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 10/16/2018] [Indexed: 05/28/2023]
Abstract
BACKGROUND In addition to its outstanding cellulase production ability, Trichoderma reesei produces a wide variety of valuable secondary metabolites, the production of which has not received much attention to date. Among them, sorbicillinoids, a large group of hexaketide secondary metabolites derived from polyketides, are drawing a growing interest from researchers because they exhibit a variety of important biological functions, including anticancer, antioxidant, antiviral, and antimicrobial properties. The development of fungi strains with constitutive, hyperproduction of sorbicillinoids is thus desired for future industry application but is not well-studied. Moreover, although T. reesei has been demonstrated to produce sorbicillinoids with the corresponding gene cluster and biosynthesis pathway proposed, the underlying molecular mechanism governing sorbicillinoid biosynthesis remains unknown. RESULTS Recombinant T. reesei ZC121 was constructed from strain RUT-C30 by the insertion of the gene 12121-knockout cassette at the telomere of T. reesei chromosome IV in consideration of the off-target mutagenesis encountered during the unsuccessful deletion of gene 121121. Strain ZC121, when grown on cellulose, showed a sharp reduction of cellulase production, but yet a remarkable enhancement of sorbicillinoids production as compared to strain RUT-C30. The hyperproduction of sorbicillinoids is a constitutive process, independent of culture conditions such as carbon source, light, pH, and temperature. To the best of our knowledge, strain ZC121 displays record sorbicillinoid production levels when grown on both glucose and cellulose. Sorbicillinol and bisvertinolone are the two major sorbicillinoid compounds produced. ZC121 displayed a different morphology and markedly reduced sporulation compared to RUT-C30 but had a similar growth rate and biomass. Transcriptome analysis showed that most genes involved in cellulase production were downregulated significantly in ZC121 grown on cellulose, whereas remarkably all genes in the sorbicillinoid gene cluster were upregulated on both cellulose and glucose. CONCLUSION A constitutive sorbicillinoid-hyperproduction strain T. reesei ZC121 was obtained by off-target mutagenesis, displaying an overwhelming shift from cellulase production to sorbicillinoid production on cellulose, leading to a record for sorbicillinoid production. For the first time, T. reesei degraded cellulose to produce platform chemical compounds other than protein in high yield. We propose that the off-target mutagenesis occurring at the telomere region might cause chromosome remodeling and subsequently alter the cell structure and the global gene expression pattern of strain ZC121, as shown by phenotype profiling and comparative transcriptome analysis of ZC121. Overall, T. reesei ZC121 holds great promise for the industrial production of sorbicillinoids and serves as a good model to explore the regulation mechanism of sorbicillinoids' biosynthesis.
Collapse
Affiliation(s)
- Chengcheng Li
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096 China
| | - Fengming Lin
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096 China
- Nanjing, China
| | - Wei Sun
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096 China
| | - Shaoxun Yuan
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096 China
| | - Zhihua Zhou
- Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032 China
| | - Fu-Gen Wu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096 China
| | - Zhan Chen
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, MI 48109 USA
| |
Collapse
|
14
|
Zhang T, Ren P, De Jesus M, Chaturvedi V, Chaturvedi S. Green Fluorescent Protein Expression in Pseudogymnoascus destructans to Study Its Abiotic and Biotic Lifestyles. Mycopathologia 2018; 183:805-814. [PMID: 29987576 DOI: 10.1007/s11046-018-0285-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 06/28/2018] [Indexed: 12/11/2022]
Abstract
Pseudogymnoascus destructans (Pd) is the etiologic agent of bat White-nose syndrome, a disease that has caused the unprecedented reduction in the hibernating bat populations across eastern North America. The Pd pathogenesis appears to be a complex adaptation of fungus in its abiotic (caves and mines) and biotic (bats) environments. There is a general lack of experimental tools for the study of Pd biology. We described the successful expression of codon-optimized synthetic green fluorescent protein sGFP in Pd. The sGFP(S65T) gene was first fused in frame with the Aspergillus nidulans promoter in the tumor-inducing plasmid pRF-HUE, and the resulting plasmid pHUE-sGFP(S65T) was transformed into Pd by Agrobacterium tumefaciens-mediated transformation system. The integration of sGFP(S65T) in Pd genome was analyzed by PCR, and single integration frequency of approximately 66% was confirmed by Southern hybridization. Fluorescent microscopy and flow cytometric analyses of two randomly selected transformants with single integration revealed high expression of sGFP in both spores and hyphal structures. The biology of mutants as judged by sporulation, growth rate, and urease production was not altered indicating sGFP is not toxic to Pd. Thus, we have generated a valuable tool that will facilitate the elucidation of Pd biology, ecology, and pathogenicity in real time.
Collapse
Affiliation(s)
- Tao Zhang
- Mycology Laboratory, Wadsworth Center, New York State Department of Health, Albany, NY, USA
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, People's Republic of China
| | - Ping Ren
- Mycology Laboratory, Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Magdia De Jesus
- Immunology and Infectious Disease Laboratory, Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Vishnu Chaturvedi
- Mycology Laboratory, Wadsworth Center, New York State Department of Health, Albany, NY, USA.
- Department of Biomedical Sciences, School of Public Health, University at Albany, Albany, NY, USA.
| | - Sudha Chaturvedi
- Mycology Laboratory, Wadsworth Center, New York State Department of Health, Albany, NY, USA.
- Department of Biomedical Sciences, School of Public Health, University at Albany, Albany, NY, USA.
| |
Collapse
|
15
|
Jang IS, Yu BJ, Jang JY, Jegal J, Lee JY. Improving the efficiency of homologous recombination by chemical and biological approaches in Yarrowia lipolytica. PLoS One 2018; 13:e0194954. [PMID: 29566071 PMCID: PMC5864075 DOI: 10.1371/journal.pone.0194954] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 03/13/2018] [Indexed: 11/18/2022] Open
Abstract
Gene targeting is a challenge in Yarrowia lipolytica (Y. lipolytica) where non-homologous end-joining (NHEJ) is predominant over homologous recombination (HR). To improve the frequency and efficiency of HR in Y. lipolytica, the ku70 gene responsible for a double stand break (DSB) repair in the NHEJ pathway was disrupted, and the cell cycle was synchronized to the S-phase with hydroxyurea, respectively. Consequently, the HR frequency was over 46% with very short homology regions (50 bp): the pex10 gene was accurately deleted at a frequency of 60% and the β-carotene biosynthetic genes were integrated at the correct locus at an average frequency of 53%. For repeated use, the URA3 marker gene was also excised and deleted at a frequency of 100% by HR between the 100 bp homology regions flanking the URA3 gene. It was shown that appropriate combination of these chemical and biological approaches was very effective to promote HR and construct genetically modified Y. lipolytica strains for biotechnological applications.
Collapse
Affiliation(s)
- In-Seung Jang
- Center for Bio-based Chemistry, Korea Research Institute of Chemical Technology (KRICT), Jongga-ro, Jung-gu, Ulsan, Republic of Korea
- Intelligent Sustainable Materials R&D Group, Research Institute of Sustainable Manufacturing System, Korea Institute of Industrial Technology (KITECH), Yandaegiro-gil, Ipjang-myeon, Seobuk-gu, Cheonan-si, Chungcheongnam-do, Republic of Korea
| | - Byung Jo Yu
- Intelligent Sustainable Materials R&D Group, Research Institute of Sustainable Manufacturing System, Korea Institute of Industrial Technology (KITECH), Yandaegiro-gil, Ipjang-myeon, Seobuk-gu, Cheonan-si, Chungcheongnam-do, Republic of Korea
| | - Ji Yeon Jang
- Intelligent Sustainable Materials R&D Group, Research Institute of Sustainable Manufacturing System, Korea Institute of Industrial Technology (KITECH), Yandaegiro-gil, Ipjang-myeon, Seobuk-gu, Cheonan-si, Chungcheongnam-do, Republic of Korea
| | - Jonggeon Jegal
- Center for Bio-based Chemistry, Korea Research Institute of Chemical Technology (KRICT), Jongga-ro, Jung-gu, Ulsan, Republic of Korea
| | - Ju Young Lee
- Center for Bio-based Chemistry, Korea Research Institute of Chemical Technology (KRICT), Jongga-ro, Jung-gu, Ulsan, Republic of Korea
- * E-mail:
| |
Collapse
|
16
|
Gaponenko AK, Mishutkina YV, Timoshenko AA, Shulga OA. Genetic Transformation of Wheat: State of the Art. RUSS J GENET+ 2018. [DOI: 10.1134/s1022795418030043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
|
17
|
Liu Y, Koh CMJ, Yap SA, Du M, Hlaing MM, Ji L. Identification of novel genes in the carotenogenic and oleaginous yeast Rhodotorula toruloides through genome-wide insertional mutagenesis. BMC Microbiol 2018; 18:14. [PMID: 29466942 PMCID: PMC5822628 DOI: 10.1186/s12866-018-1151-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 01/30/2018] [Indexed: 01/15/2023] Open
Abstract
Background Rhodotorula toruloides is an outstanding producer of lipids and carotenoids. Currently, information on the key metabolic pathways and their molecular basis of regulation remains scarce, severely limiting efforts to engineer it as an industrial host. Results We have adapted Agrobacterium tumefaciens-mediated transformation (ATMT) as a gene-tagging tool for the identification of novel genes in R. toruloides. Multiple factors affecting transformation efficiency in several species in the Pucciniomycotina subphylum were optimized. The Agrobacterium transfer DNA (T-DNA) showed predominantly single-copy chromosomal integrations in R. toruloides, which were trackable by high efficiency thermal asymmetric interlaced PCR (hiTAIL-PCR). To demonstrate the application of random T-DNA insertions for strain improvement and gene hunting, 3 T-DNA insertional libraries were screened against cerulenin, nile red and tetrazolium violet respectively, resulting in the identification of 22 mutants with obvious phenotypes in fatty acid or lipid metabolism. Similarly, 5 carotenoid biosynthetic mutants were obtained through visual screening of the transformants. To further validate the gene tagging strategy, one of the carotenoid production mutants, RAM5, was analyzed in detail. The mutant had a T-DNA inserted at the putative phytoene desaturase gene CAR1. Deletion of CAR1 by homologous recombination led to a phenotype similar to RAM5 and it could be genetically complemented by re-introduction of the wild-type CAR1 genome sequence. Conclusions T-DNA insertional mutagenesis is an efficient forward genetic tool for gene discovery in R. toruloides and related oleaginous yeast species. It is also valuable for metabolic engineering in these hosts. Further analysis of the 27 mutants identified in this study should augment our knowledge of the lipid and carotenoid biosynthesis, which may be exploited for oil and isoprenoid metabolic engineering. Electronic supplementary material The online version of this article (10.1186/s12866-018-1151-6) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Yanbin Liu
- Biomaterials and Biocatalysts Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore.
| | - Chong Mei John Koh
- Biomaterials and Biocatalysts Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore
| | - Sihui Amy Yap
- Biomaterials and Biocatalysts Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore
| | - Minge Du
- Biomaterials and Biocatalysts Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore
| | - Mya Myintzu Hlaing
- Biomaterials and Biocatalysts Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore
| | - Lianghui Ji
- Biomaterials and Biocatalysts Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore. .,School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore.
| |
Collapse
|
18
|
Hooykaas PJJ, van Heusden GPH, Niu X, Reza Roushan M, Soltani J, Zhang X, van der Zaal BJ. Agrobacterium-Mediated Transformation of Yeast and Fungi. Curr Top Microbiol Immunol 2018; 418:349-374. [PMID: 29770864 DOI: 10.1007/82_2018_90] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Two decades ago, it was discovered that the well-known plant vector Agrobacterium tumefaciens can also transform yeasts and fungi when these microorganisms are co-cultivated on a solid substrate in the presence of a phenolic inducer such as acetosyringone. It is important that the medium has a low pH (5-6) and that the temperature is kept at room temperature (20-25 °C) during co-cultivation. Nowadays, Agrobacterium-mediated transformation (AMT) is the method of choice for the transformation of many fungal species; as the method is simple, the transformation efficiencies are much higher than with other methods, and AMT leads to single-copy integration much more frequently than do other methods. Integration of T-DNA in fungi occurs by non-homologous end-joining (NHEJ), but also targeted integration of the T-DNA by homologous recombination (HR) is possible. In contrast to AMT of plants, which relies on the assistance of a number of translocated virulence (effector) proteins, none of these (VirE2, VirE3, VirD5, VirF) are necessary for AMT of yeast or fungi. This is in line with the idea that some of these proteins help to overcome plant defense. Importantly, it also showed that VirE2 is not necessary for the transport of the T-strand into the nucleus. The yeast Saccharomyces cerevisiae is a fast-growing organism with a relatively simple genome with reduced genetic redundancy. This yeast species has therefore been used to unravel basic molecular processes in eukaryotic cells as well as to elucidate the function of virulence factors of pathogenic microorganisms acting in plants or animals. Translocation of Agrobacterium virulence proteins into yeast was recently visualized in real time by confocal microscopy. In addition, the yeast 2-hybrid system, one of many tools that have been developed for use in this yeast, was used to identify plant and yeast proteins interacting with the translocated Agrobacterium virulence proteins. Dedicated mutant libraries, containing for each gene a mutant with a precise deletion, have been used to unravel the mode of action of some of the Agrobacterium virulence proteins. Yeast deletion mutant collections were also helpful in identifying host factors promoting or inhibiting AMT, including factors involved in T-DNA integration. Thus, the homologous recombination (HR) factor Rad52 was found to be essential for targeted integration of T-DNA by HR in yeast. Proteins mediating double-strand break (DSB) repair by end-joining (Ku70, Ku80, Lig4) turned out to be essential for non-homologous integration. Inactivation of any one of the genes encoding these end-joining factors in other yeasts and fungi was employed to reduce or totally eliminate non-homologous integration and promote efficient targeted integration at the homologous locus by HR. In plants, however, their inactivation did not prevent non-homologous integration, indicating that T-DNA is captured by different DNA repair pathways in plants and fungi.
Collapse
Affiliation(s)
- Paul J J Hooykaas
- Sylvius Lab, Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands.
| | - G Paul H van Heusden
- Sylvius Lab, Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
| | - Xiaolei Niu
- Sylvius Lab, Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
| | - M Reza Roushan
- Sylvius Lab, Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
| | - Jalal Soltani
- Sylvius Lab, Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
| | - Xiaorong Zhang
- Sylvius Lab, Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
| | - Bert J van der Zaal
- Sylvius Lab, Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
| |
Collapse
|
19
|
Abstract
Agrobacterium strains transfer a single-strand form of T-DNA (T-strands) and Virulence (Vir) effector proteins to plant cells. Following transfer, T-strands likely form complexes with Vir and plant proteins that traffic through the cytoplasm and enter the nucleus. T-strands may subsequently randomly integrate into plant chromosomes and permanently express encoded transgenes, a process known as stable transformation. The molecular processes by which T-strands integrate into the host genome remain unknown. Although integration resembles DNA repair processes, the requirement of known DNA repair pathways for integration is controversial. The configuration and genomic position of integrated T-DNA molecules likely affect transgene expression, and control of integration is consequently important for basic research and agricultural biotechnology applications. This article reviews our current knowledge of the process of T-DNA integration and proposes ways in which this knowledge may be manipulated for genome editing and synthetic biology purposes.
Collapse
Affiliation(s)
- Stanton B Gelvin
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907-1392, USA;
| |
Collapse
|
20
|
Hwang HH, Yu M, Lai EM. Agrobacterium-mediated plant transformation: biology and applications. THE ARABIDOPSIS BOOK 2017; 15:e0186. [PMID: 31068763 PMCID: PMC6501860 DOI: 10.1199/tab.0186] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Plant genetic transformation heavily relies on the bacterial pathogen Agrobacterium tumefaciens as a powerful tool to deliver genes of interest into a host plant. Inside the plant nucleus, the transferred DNA is capable of integrating into the plant genome for inheritance to the next generation (i.e. stable transformation). Alternatively, the foreign DNA can transiently remain in the nucleus without integrating into the genome but still be transcribed to produce desirable gene products (i.e. transient transformation). From the discovery of A. tumefaciens to its wide application in plant biotechnology, numerous aspects of the interaction between A. tumefaciens and plants have been elucidated. This article aims to provide a comprehensive review of the biology and the applications of Agrobacterium-mediated plant transformation, which may be useful for both microbiologists and plant biologists who desire a better understanding of plant transformation, protein expression in plants, and plant-microbe interaction.
Collapse
Affiliation(s)
- Hau-Hsuan Hwang
- Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan, 402
| | - Manda Yu
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, 115
| | - Erh-Min Lai
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, 115
| |
Collapse
|
21
|
Idnurm A, Bailey AM, Cairns TC, Elliott CE, Foster GD, Ianiri G, Jeon J. A silver bullet in a golden age of functional genomics: the impact of Agrobacterium-mediated transformation of fungi. Fungal Biol Biotechnol 2017; 4:6. [PMID: 28955474 PMCID: PMC5615635 DOI: 10.1186/s40694-017-0035-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 09/18/2017] [Indexed: 11/10/2022] Open
Abstract
The implementation of Agrobacterium tumefaciens as a transformation tool revolutionized approaches to discover and understand gene functions in a large number of fungal species. A. tumefaciens mediated transformation (AtMT) is one of the most transformative technologies for research on fungi developed in the last 20 years, a development arguably only surpassed by the impact of genomics. AtMT has been widely applied in forward genetics, whereby generation of strain libraries using random T-DNA insertional mutagenesis, combined with phenotypic screening, has enabled the genetic basis of many processes to be elucidated. Alternatively, AtMT has been fundamental for reverse genetics, where mutant isolates are generated with targeted gene deletions or disruptions, enabling gene functional roles to be determined. When combined with concomitant advances in genomics, both forward and reverse approaches using AtMT have enabled complex fungal phenotypes to be dissected at the molecular and genetic level. Additionally, in several cases AtMT has paved the way for the development of new species to act as models for specific areas of fungal biology, particularly in plant pathogenic ascomycetes and in a number of basidiomycete species. Despite its impact, the implementation of AtMT has been uneven in the fungi. This review provides insight into the dynamics of expansion of new research tools into a large research community and across multiple organisms. As such, AtMT in the fungi, beyond the demonstrated and continuing power for gene discovery and as a facile transformation tool, provides a model to understand how other technologies that are just being pioneered, e.g. CRISPR/Cas, may play roles in fungi and other eukaryotic species.
Collapse
Affiliation(s)
- Alexander Idnurm
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010 Australia
| | - Andy M. Bailey
- School of Biological Sciences, University of Bristol, Bristol, UK
| | - Timothy C. Cairns
- Department of Applied and Molecular Microbiology, Technische Universität Berlin, Berlin, Germany
| | - Candace E. Elliott
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010 Australia
| | - Gary D. Foster
- School of Biological Sciences, University of Bristol, Bristol, UK
| | - Giuseppe Ianiri
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, USA
| | - Junhyun Jeon
- College of Life and Applied Sciences, Yeungnam University, Gyeongsan, South Korea
| |
Collapse
|
22
|
Ohmine Y, Satoh Y, Kiyokawa K, Yamamoto S, Moriguchi K, Suzuki K. DNA repair genes RAD52 and SRS2, a cell wall synthesis regulator gene SMI1, and the membrane sterol synthesis scaffold gene ERG28 are important in efficient Agrobacterium-mediated yeast transformation with chromosomal T-DNA. BMC Microbiol 2016; 16:58. [PMID: 27038795 PMCID: PMC4818910 DOI: 10.1186/s12866-016-0672-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 03/16/2016] [Indexed: 11/25/2022] Open
Abstract
Background Plant pathogenic Agrobacterium strains can transfer T-DNA regions of their Ti plasmids to a broad range of eukaryotic hosts, including fungi, in vitro. In the recent decade, the yeast Saccharomyces cerevisiae is used as a model host to reveal important host proteins for the Agrobacterium-mediated transformation (AMT). Further investigation is required to understand the fundamental mechanism of AMT, including interaction at the cell surface, to expand the host range, and to develop new tools. In this study, we screened a yeast mutant library for low AMT mutant strains by advantage of a chromosome type T-DNA, which transfer is efficient and independent on integration into host chromosome. Results By the mutant screening, we identified four mutant strains (srs2Δ, rad52Δ, smi1Δ and erg28Δ), which showed considerably low AMT efficiency. Structural analysis of T-DNA product replicons in AMT colonies of mutants lacking each of the two DNA repair genes, SRS2 and RAD52, suggested that the genes act soon after T-DNA entry for modification of the chromosomal T-DNA to stably maintain them as linear replicons and to circularize certain T-DNA simultaneously. The cell wall synthesis regulator SMI1 might have a role in the cell surface interaction between the donor and recipient cells, but the smi1Δ mutant exhibited pleiotropic effect, i.e. low effector protein transport as well as low AMT for the chromosomal T-DNA, but relatively high AMT for integrative T-DNAs. The ergosterol synthesis regulator/enzyme-scaffold gene ERG28 probably contributes by sensing a congested environment, because growth of erg28Δ strain was unaffected by the presence of donor bacterial cells, while the growth of the wild-type and other mutant yeast strains was suppressed by their presence. Conclusions RAD52 and the DNA helicase/anti-recombinase gene SRS2 are necessary to form and maintain artificial chromosomes through the AMT of chromosomal T-DNA. A sterol synthesis scaffold gene ERG28 is important in the high-efficiency AMT, possibly by avoiding congestion. The involvement of the cell wall synthesis regulator SMI1 remains to be elucidated.
Collapse
Affiliation(s)
- Yuta Ohmine
- Department of Biological Science, Graduate School of Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima, Hiroshima, 739-8526, Japan
| | - Yukari Satoh
- Department of Biological Science, Graduate School of Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima, Hiroshima, 739-8526, Japan
| | - Kazuya Kiyokawa
- Department of Biological Science, Graduate School of Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima, Hiroshima, 739-8526, Japan
| | - Shinji Yamamoto
- Department of Biological Science, Graduate School of Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima, Hiroshima, 739-8526, Japan
| | - Kazuki Moriguchi
- Department of Biological Science, Graduate School of Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima, Hiroshima, 739-8526, Japan
| | - Katsunori Suzuki
- Department of Biological Science, Graduate School of Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima, Hiroshima, 739-8526, Japan.
| |
Collapse
|
23
|
Gandía M, Xu S, Font C, Marcos JF. Disruption of ku70 involved in non-homologous end-joining facilitates homologous recombination but increases temperature sensitivity in the phytopathogenic fungus Penicillium digitatum. Fungal Biol 2015; 120:317-23. [PMID: 26895860 DOI: 10.1016/j.funbio.2015.11.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Revised: 11/04/2015] [Accepted: 11/05/2015] [Indexed: 12/22/2022]
Abstract
The dominant mechanism to repair double-stranded DNA breaks in filamentous fungi is the non-homologous end joining (NHEJ) pathway, and not the homologous recombination (HR) pathway that operates in the mutation of genes by replacement of target DNA for selection cassettes. The key to improve HR frequency is the inactivation of the NHEJ pathway by eliminating components of its Ku70/80 heterodimeric complex. We have obtained ku70 mutants of Penicillium digitatum, the main citrus postharvest pathogen. The increased efficiency of HR in Δku70 strains was demonstrated by the generation of mutants in two different chitin synthase genes (PdchsII and PdchsV). P. digitatum Δku70 strains showed no differences from the parental strain in vegetative growth, asexual development or virulence to citrus fruit, when experiments were conducted at the optimal temperature of 24°C. However, growth of Δku70 strains at temperatures higher than 24°C demonstrated a detrimental effect in axenic growth and conidia production. These observations are in agreement with previous studies describing differences between ku70 mutants and their parental strains in some fungal species, and must be taken into account for future applications of the Δku approach to increase HR efficiency in fungi.
Collapse
Affiliation(s)
- Mónica Gandía
- Food Science Department, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Avda Agustín Escardino 7, 46980 Paterna, Valencia, Spain.
| | - Shaomei Xu
- Food Science Department, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Avda Agustín Escardino 7, 46980 Paterna, Valencia, Spain.
| | - Cristina Font
- Food Science Department, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Avda Agustín Escardino 7, 46980 Paterna, Valencia, Spain.
| | - Jose F Marcos
- Food Science Department, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Avda Agustín Escardino 7, 46980 Paterna, Valencia, Spain.
| |
Collapse
|
24
|
Suzuki K, Moriguchi K, Yamamoto S. Horizontal DNA transfer from bacteria to eukaryotes and a lesson from experimental transfers. Res Microbiol 2015; 166:753-63. [PMID: 26291765 DOI: 10.1016/j.resmic.2015.08.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2015] [Revised: 08/04/2015] [Accepted: 08/05/2015] [Indexed: 11/15/2022]
Abstract
Horizontal gene transfer (HGT) is widespread among bacteria and plays a key role in genome dynamics. HGT is much less common in eukaryotes, but is being reported with increasing frequency in eukaryotes. The mechanism as to how eukaryotes acquired genes from distantly related organisms remains obscure yet. This paper cites examples of bacteria-derived genes found in eukaryotic organisms, and then describes experimental DNA transports to eukaryotes by bacterial type 4 secretion systems in optimized conditions. The mechanisms of the latter are efficient, quite reproducible in vitro and predictable, and thereby would provide insight into natural HGT and to the development of new research tools.
Collapse
|
25
|
Tsakraklides V, Brevnova E, Stephanopoulos G, Shaw AJ. Improved Gene Targeting through Cell Cycle Synchronization. PLoS One 2015; 10:e0133434. [PMID: 26192309 PMCID: PMC4507847 DOI: 10.1371/journal.pone.0133434] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 06/26/2015] [Indexed: 01/27/2023] Open
Abstract
Gene targeting is a challenge in organisms where non-homologous end-joining is the predominant form of recombination. We show that cell division cycle synchronization can be applied to significantly increase the rate of homologous recombination during transformation. Using hydroxyurea-mediated cell cycle arrest, we obtained improved gene targeting rates in Yarrowia lipolytica, Arxula adeninivorans, Saccharomyces cerevisiae, Kluyveromyces lactis and Pichia pastoris demonstrating the broad applicability of the method. Hydroxyurea treatment enriches for S-phase cells that are active in homologous recombination and enables previously unattainable genomic modifications.
Collapse
Affiliation(s)
| | - Elena Brevnova
- Total New Energies, Emeryville, California, United States of America
| | - Gregory Stephanopoulos
- Novogy Inc., Cambridge, Massachusetts, United States of America
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - A. Joe Shaw
- Novogy Inc., Cambridge, Massachusetts, United States of America
| |
Collapse
|
26
|
Liu R, Chen L, Jiang Y, Zhou Z, Zou G. Efficient genome editing in filamentous fungus Trichoderma reesei using the CRISPR/Cas9 system. Cell Discov 2015; 1:15007. [PMID: 27462408 PMCID: PMC4860831 DOI: 10.1038/celldisc.2015.7] [Citation(s) in RCA: 281] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2014] [Accepted: 02/28/2015] [Indexed: 02/03/2023] Open
Abstract
Filamentous fungi have wide applications in biotechnology. The CRISPR/Cas9 system is a powerful genome-editing method that facilitates genetic alterations of genomes in a variety of organisms. However, a genome-editing approach has not been reported in filamentous fungi. Here, we demonstrated the establishment of a CRISPR/Cas9 system in the filamentous fungus Trichoderma reesei by specific codon optimization and in vitro RNA transcription. It was shown that the CRISPR/Cas9 system was controllable and conditional through inducible Cas9 expression. This system generated site-specific mutations in target genes through efficient homologous recombination, even using short homology arms. This system also provided an applicable and promising approach to targeting multiple genes simultaneously. Our results illustrate that the CRISPR/Cas9 system is a powerful genome-manipulating tool for T. reesei and most likely for other filamentous fungal species, which may accelerate studies on functional genomics and strain improvement in these filamentous fungi.
Collapse
Affiliation(s)
- Rui Liu
- CAS-Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences , Shanghai, China
| | - Ling Chen
- CAS-Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences , Shanghai, China
| | - Yanping Jiang
- CAS-Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences , Shanghai, China
| | - Zhihua Zhou
- CAS-Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences , Shanghai, China
| | - Gen Zou
- CAS-Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences , Shanghai, China
| |
Collapse
|
27
|
Ecologically Driven Competence for Exogenous DNA Uptake in Yeast. Curr Microbiol 2015; 70:883-93. [DOI: 10.1007/s00284-015-0808-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 02/20/2015] [Indexed: 01/03/2023]
|
28
|
Park SY, Vaghchhipawala Z, Vasudevan B, Lee LY, Shen Y, Singer K, Waterworth WM, Zhang ZJ, West CE, Mysore KS, Gelvin SB. Agrobacterium T-DNA integration into the plant genome can occur without the activity of key non-homologous end-joining proteins. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 81:934-46. [PMID: 25641249 DOI: 10.1111/tpj.12779] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 01/19/2015] [Accepted: 01/20/2015] [Indexed: 05/29/2023]
Abstract
Non-homologous end joining (NHEJ) is the major model proposed for Agrobacterium T-DNA integration into the plant genome. In animal cells, several proteins, including KU70, KU80, ARTEMIS, DNA-PKcs, DNA ligase IV (LIG4), Ataxia telangiectasia mutated (ATM), and ATM- and Rad3-related (ATR), play an important role in 'classical' (c)NHEJ. Other proteins, including histone H1 (HON1), XRCC1, and PARP1, participate in a 'backup' (b)NHEJ process. We examined transient and stable transformation frequencies of Arabidopsis thaliana roots mutant for numerous NHEJ and other related genes. Mutants of KU70, KU80, and the plant-specific DNA Ligase VI (LIG6) showed increased stable transformation susceptibility. However, these mutants showed transient transformation susceptibility similar to that of wild-type plants, suggesting enhanced T-DNA integration in these mutants. These results were confirmed using a promoter-trap transformation vector that requires T-DNA integration into the plant genome to activate a promoterless gusA (uidA) gene, by virus-induced gene silencing (VIGS) of Nicotiana benthamiana NHEJ genes, and by biochemical assays for T-DNA integration. No alteration in transient or stable transformation frequencies was detected with atm, atr, lig4, xrcc1, or parp1 mutants. However, mutation of parp1 caused high levels of T-DNA integration and transgene methylation. A double mutant (ku80/parp1), knocking out components of both NHEJ pathways, did not show any decrease in stable transformation or T-DNA integration. Thus, T-DNA integration does not require known NHEJ proteins, suggesting an alternative route for integration.
Collapse
Affiliation(s)
- So-Yon Park
- Department of Biological Sciences, Purdue University, West Lafayette, IN, 47907, USA; Plant Transformation Core Facility, University of Missouri, Columbia, MO, 65211, USA; Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg, VA, 24061, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Enhanced targeted integration mediated by translocated I-SceI during the Agrobacterium mediated transformation of yeast. Sci Rep 2015; 5:8345. [PMID: 25662162 PMCID: PMC4648448 DOI: 10.1038/srep08345] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 01/15/2015] [Indexed: 12/21/2022] Open
Abstract
Agrobacterium mediated transformation (AMT) has been embraced by biotechnologists as the technology of choice to introduce or alter genetic traits of plants. However, in plants it is virtually impossible to predetermine the integration site of the transferred T-strand unless one is able to generate a double stranded break (DSB) in the DNA at the site of interest. In this study, we used the model organism Saccharomyces cerevisiae to investigate whether the Agrobacterium mediated translocation of site-specific endonucleases via the type IV secretion system (T4SS), concomitantly with T-DNA transfer is possible and whether this can improve the gene targeting efficiency. In addition to that, the effect of different chromatin states on targeted integration, was investigated. It was found that Agrobacterium mediated translocation of the homing endonuclease I-SceI has a positive effect on the integration of T-DNA via the homologous repair (HR) pathway. Furthermore, we obtained evidence that nucleosome removal has a positive effect on I-SceI facilitated T-DNA integration by HR. Reversely; inducing nucleosome formation at the site of integration removes the positive effect of translocated I-SceI on T-DNA integration.
Collapse
|
30
|
Agrobacterium tumefaciens-Mediated Transformation. Fungal Biol 2015. [DOI: 10.1007/978-3-319-10142-2_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
31
|
Rolloos M, Dohmen MHC, Hooykaas PJJ, van der Zaal BJ. Involvement of Rad52 in T-DNA circle formation duringAgrobacterium tumefaciens-mediated transformation ofSaccharomyces cerevisiae. Mol Microbiol 2014; 91:1240-51. [DOI: 10.1111/mmi.12531] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/24/2014] [Indexed: 11/26/2022]
Affiliation(s)
- Martijn Rolloos
- Department of Molecular and Developmental Genetics; nstitute of Biology Leiden; Leiden Sylviusweg 72, 2333 BE The Netherlands
| | - Marius H. C. Dohmen
- Department of Molecular and Developmental Genetics; nstitute of Biology Leiden; Leiden Sylviusweg 72, 2333 BE The Netherlands
| | - Paul J. J. Hooykaas
- Department of Molecular and Developmental Genetics; nstitute of Biology Leiden; Leiden Sylviusweg 72, 2333 BE The Netherlands
| | - Bert J. van der Zaal
- Department of Molecular and Developmental Genetics; nstitute of Biology Leiden; Leiden Sylviusweg 72, 2333 BE The Netherlands
| |
Collapse
|
32
|
Mestiri I, Norre F, Gallego ME, White CI. Multiple host-cell recombination pathways act in Agrobacterium-mediated transformation of plant cells. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2014; 77:511-20. [PMID: 24299074 DOI: 10.1111/tpj.12398] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 11/16/2013] [Accepted: 11/28/2013] [Indexed: 05/11/2023]
Abstract
Using floral-dip, tumorigenesis and root callus transformation assays of both germline and somatic cells, we present here results implicating the four major non-homologous and homologous recombination pathways in Agrobacterium-mediated transformation of Arabidopsis thaliana. All four single mutant lines showed similar mild reductions in transformability, but knocking out three of four pathways severely compromised Agrobacterium-mediated transformation. Although integration of T-DNA into the plant genome is severely compromised in the absence of known DNA double-strand break repair pathways, it does still occur, suggesting the existence of other pathways involved in T-DNA integration. Our results highlight the functional redundancy of the four major plant recombination pathways in transformation, and provide an explanation for the lack of strong effects observed in previous studies on the roles of plant recombination functions in transformation.
Collapse
Affiliation(s)
- Imen Mestiri
- Génétique, Reproduction et Développement, UMR CNRS 6293, Clermont Université, INSERM U1103, UFR Sciences et Technologies, Université Blaise Pascal, 24 avenue des Landais, BP80026, 63171, Aubière Cedex, France
| | | | | | | |
Collapse
|
33
|
Saika H, Nishizawa-Yokoi A, Toki S. The non-homologous end-joining pathway is involved in stable transformation in rice. FRONTIERS IN PLANT SCIENCE 2014; 5:560. [PMID: 25368624 PMCID: PMC4201092 DOI: 10.3389/fpls.2014.00560] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 09/29/2014] [Indexed: 05/20/2023]
Abstract
Stable transformation with T-DNA needs the coordinated activities of many proteins derived from both host plant cells and Agrobacterium. In dicot plants, including Arabidopsis, it has been suggested that non-homologous end-joining (NHEJ)-one of the main DNA double-strand break repair pathways-is involved in the T-DNA integration step that is crucial to stable transformation. However, how this pathway is involved remains unclear as results with NHEJ mutants in Arabidopsis have given inconsistent results. Recently, a system for visualization of stable expression of genes located on T-DNA has been established in rice callus. Stable expression was shown to be reduced significantly in NHEJ knock-down rice calli, suggesting strongly that NHEJ is involved in Agrobacterium-mediated stable transformation in rice. Since rice transformation is now efficient and reproducible, rice is a good model plant in which to elucidate the molecular mechanisms of T-DNA integration.
Collapse
Affiliation(s)
- Hiroaki Saika
- Plant Genome Engineering Research Unit, Agrogenomics Research Center, National Institute of Agrobiological SciencesTsukuba, Japan
- *Correspondence: Hiroaki Saika, Plant Genome Engineering Research Unit, Agrogenomics Research Center, National Institute of Agrobiological Sciences, 2-1-2 Kannondai, Tsukuba, Ibaraki 305-8602, Japan e-mail:
| | - Ayako Nishizawa-Yokoi
- Plant Genome Engineering Research Unit, Agrogenomics Research Center, National Institute of Agrobiological SciencesTsukuba, Japan
| | - Seiichi Toki
- Plant Genome Engineering Research Unit, Agrogenomics Research Center, National Institute of Agrobiological SciencesTsukuba, Japan
- Kihara Institute for Biological Research, Yokohama City UniversityYokohama, Japan
| |
Collapse
|
34
|
Bilichak A, Kovalchuk I. Manipulation of epigenetic factors and the DNA repair machinery for improving the frequency of plant transformation. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2014. [DOI: 10.1016/j.bcab.2013.08.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
35
|
Elmer JJ, Christensen MD, Rege K. Applying horizontal gene transfer phenomena to enhance non-viral gene therapy. J Control Release 2013; 172:246-257. [PMID: 23994344 PMCID: PMC4258102 DOI: 10.1016/j.jconrel.2013.08.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 08/17/2013] [Accepted: 08/20/2013] [Indexed: 12/25/2022]
Abstract
Horizontal gene transfer (HGT) is widespread amongst prokaryotes, but eukaryotes tend to be far less promiscuous with their genetic information. However, several examples of HGT from pathogens into eukaryotic cells have been discovered and mimicked to improve non-viral gene delivery techniques. For example, several viral proteins and DNA sequences have been used to significantly increase cytoplasmic and nuclear gene delivery. Plant genetic engineering is routinely performed with the pathogenic bacterium Agrobacterium tumefaciens and similar pathogens (e.g. Bartonella henselae) may also be able to transform human cells. Intracellular parasites like Trypanosoma cruzi may also provide new insights into overcoming cellular barriers to gene delivery. Finally, intercellular nucleic acid transfer between host cells will also be briefly discussed. This article will review the unique characteristics of several different viruses and microbes and discuss how their traits have been successfully applied to improve non-viral gene delivery techniques. Consequently, pathogenic traits that originally caused diseases may eventually be used to treat many genetic diseases.
Collapse
Affiliation(s)
- Jacob J Elmer
- Department of Chemical Engineering, Villanova University, Villanova 19085, USA.
| | | | - Kaushal Rege
- Chemical Engineering, Arizona State University, Tempe 85287-6106, USA.
| |
Collapse
|
36
|
Zhou X, Wang K, Lv D, Wu C, Li J, Zhao P, Lin Z, Du L, Yan Y, Ye X. Global analysis of differentially expressed genes and proteins in the wheat callus infected by Agrobacterium tumefaciens. PLoS One 2013; 8:e79390. [PMID: 24278131 PMCID: PMC3835833 DOI: 10.1371/journal.pone.0079390] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2013] [Accepted: 09/20/2013] [Indexed: 12/24/2022] Open
Abstract
Agrobacterium-mediated plant transformation is an extremely complex and evolved process involving genetic determinants of both the bacteria and the host plant cells. However, the mechanism of the determinants remains obscure, especially in some cereal crops such as wheat, which is recalcitrant for Agrobacterium-mediated transformation. In this study, differentially expressed genes (DEGs) and differentially expressed proteins (DEPs) were analyzed in wheat callus cells co-cultured with Agrobacterium by using RNA sequencing (RNA-seq) and two-dimensional electrophoresis (2-DE) in conjunction with mass spectrometry (MS). A set of 4,889 DEGs and 90 DEPs were identified, respectively. Most of them are related to metabolism, chromatin assembly or disassembly and immune defense. After comparative analysis, 24 of the 90 DEPs were detected in RNA-seq and proteomics datasets simultaneously. In addition, real-time RT-PCR experiments were performed to check the differential expression of the 24 genes, and the results were consistent with the RNA-seq data. According to gene ontology (GO) analysis, we found that a big part of these differentially expressed genes were related to the process of stress or immunity response. Several putative determinants and candidate effectors responsive to Agrobacterium mediated transformation of wheat cells were discussed. We speculate that some of these genes are possibly related to Agrobacterium infection. Our results will help to understand the interaction between Agrobacterium and host cells, and may facilitate developing efficient transformation strategies in cereal crops.
Collapse
Affiliation(s)
- Xiaohong Zhou
- National Key Facility of Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Ke Wang
- National Key Facility of Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Dongwen Lv
- Key Laboratory of Genetics and Biotechnology, College of Life Science, Capital Normal University, Beijing, China
| | - Chengjun Wu
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Jiarui Li
- Department of Plant Pathology, Kansas State University, Manhattan, Kansas, United States of America
| | - Pei Zhao
- National Key Facility of Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhishan Lin
- National Key Facility of Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Lipu Du
- National Key Facility of Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yueming Yan
- Key Laboratory of Genetics and Biotechnology, College of Life Science, Capital Normal University, Beijing, China
| | - Xingguo Ye
- National Key Facility of Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
- * E-mail:
| |
Collapse
|
37
|
Andersen MT, Liefting LW, Havukkala I, Beever RE. Comparison of the complete genome sequence of two closely related isolates of 'Candidatus Phytoplasma australiense' reveals genome plasticity. BMC Genomics 2013; 14:529. [PMID: 23915186 PMCID: PMC3750655 DOI: 10.1186/1471-2164-14-529] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 07/27/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND 'Candidatus Phytoplasma australiense' is associated with at least nine diseases in Australia and New Zealand. The impact of this phytoplasma is considerable, both economically and environmentally. The genome of a NZ isolate was sequenced in an effort to understand its pathogenicity and ecology. Comparison with a closely related Australian isolate enabled us to examine mechanisms of genomic rearrangement. RESULTS The complete genome sequence of a strawberry lethal yellows (SLY) isolate of 'Candidatus Phytoplasma australiense' was determined. It is a circular genome of 959,779 base pairs with 1126 predicted open reading frames. Despite being 80 kbp larger than another 'Ca. Phytoplasma australiense' isolate PAa, the variation between housekeeping genes was generally less than 1% at a nucleotide level. The difference in size between the two isolates was largely due to the number and size of potential mobile units (PMUs), which contributed to some changes in gene order. Comparison of the genomes of the two isolates revealed that the highly conserved 5' UTR of a putative DNA-directed RNA polymerase seems to be associated with insertion and rearrangement events. Two types of PMUs have been identified on the basis of the order of three to four conserved genes, with both PMUs appearing to have been present in the last common ancestor of 'Ca. Phytoplasma asteris' and 'Ca. Phytoplasma australiense'. Comparison with other phytoplasma genomes showed that modification methylases were, in general, species-specific. A putative methylase (xorIIM) found in 'Ca. Phytoplasma australiense' appeared to have no analogue in any other firmicute, and we believe has been introduced by way of lateral gene transfer. A putative retrostransposon (ltrA) analogous to that found in OY-M was present in both isolates, although all examples in PAa appear to be fragments. Comparative analysis identified highly conserved 5' and 3' UTR regions of ltrA, which may indicate how the gene is excised and inserted. CONCLUSIONS Comparison of two assembled 'Ca. Phytoplasma australiense' genomes has shown they possess a high level of plasticity. This comparative analysis has yielded clues as to how rearrangements occur, and the identification of sets of genes that appear to be associated with these events.
Collapse
Affiliation(s)
- Mark T Andersen
- The New Zealand Institute for Plant & Food Research Limited, Private Bag 92169, Auckland 1142, New Zealand
| | - Lia W Liefting
- AgriGenesis Biosciences Ltd, P.O. Box 50, Auckland, New Zealand
- Current address: Plant Health and Environment Laboratory, Ministry for Primary Industries, P.O. Box 2095, Auckland 1140, New Zealand
| | - Ilkka Havukkala
- AgriGenesis Biosciences Ltd, P.O. Box 50, Auckland, New Zealand
- Current address: Intellectual Property Office of New Zealand, 205 Victoria Street, Wellington, New Zealand
| | - Ross E Beever
- Landcare Research, Private Bag 92170, Auckland 1142, New Zealand
| |
Collapse
|
38
|
Transkingdom genetic transfer from Escherichia coli to Saccharomyces cerevisiae as a simple gene introduction tool. Appl Environ Microbiol 2013; 79:4393-400. [PMID: 23666333 DOI: 10.1128/aem.00770-13] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Transkingdom conjugation (TKC) permits transfer of DNA from bacteria to eukaryotic cells using a bacterial conjugal transfer system. However, it is not clear whether the process of DNA acceptance in a recipient eukaryote is homologous to the process of conjugation between bacteria. TKC transfer requires mobilizable shuttle vectors that are capable of conjugal transfer and replication in the donor and recipient strains. Here, we developed TKC vectors derived from plasmids belonging to the IncP and IncQ groups. We also investigated forms of transfer of these vectors from Escherichia coli into Saccharomyces cerevisiae to develop TKC as a simple gene introduction method. Both types of vectors were transferred precisely, conserving the origin of transfer (oriT) sequences, but IncP-based vectors appeared to be more efficient than an IncQ-based vector. Interestingly, unlike in agrobacterial T-DNA (transfer DNA) transfer, the efficiency of TKC transfer was similar between a wild-type yeast strain and DNA repair mutants defective in homologous recombination (rad51Δ and rad52Δ) or nonhomologous end joining (rad50Δ, yku70Δ, and lig4Δ). Lastly, a shuttle vector with two repeats of IncP-type oriT (oriT(P)) sequences flanking a marker gene was constructed. TKC transfer of this vector resulted in precise excision of both the oriT(P) loci as well as the marker gene, albeit at a low frequency of 17% of all transconjugants. This feature would be attractive in biotechnological applications of TKC. Taken together, these results strongly suggest that in contrast to agrobacterial T-DNA transfer, the circularization of vector single-stranded DNA occurs either before or after transfer but requires a factor(s) from the donor. TKC is a simple method of gene transfer with possible applications in yeast genetics and biotechnology.
Collapse
|
39
|
Weinthal DM, Taylor RA, Tzfira T. Nonhomologous end joining-mediated gene replacement in plant cells. PLANT PHYSIOLOGY 2013; 162:390-400. [PMID: 23509176 PMCID: PMC3641218 DOI: 10.1104/pp.112.212910] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2013] [Accepted: 02/23/2013] [Indexed: 05/19/2023]
Abstract
Stimulation of the homologous recombination DNA-repair pathway via the induction of genomic double-strand breaks (DSBs) by zinc finger nucleases (ZFNs) has been deployed for gene replacement in plant cells. Nonhomologous end joining (NHEJ)-mediated repair of DSBs, on the other hand, has been utilized for the induction of site-specific mutagenesis in plants. Since NHEJ is the dominant DSB repair pathway and can also lead to the capture of foreign DNA molecules, we suggest that it can also be deployed for gene replacement. An acceptor DNA molecule in which a green fluorescent protein (GFP) coding sequence (gfp) was flanked by ZFN recognition sequences was used to produce transgenic target plants. A donor DNA molecule in which a promoterless hygromycin B phosphotransferase-encoding gene (hpt) was flanked by ZFN recognition sequences was constructed. The donor DNA molecule and ZFN expression cassette were delivered into target plants. ZFN-mediated site-specific mutagenesis and complete removal of the GFP coding sequence resulted in the recovery of hygromycin-resistant plants that no longer expressed GFP and in which the hpt gene was unlinked to the acceptor DNA. More importantly, ZFN-mediated digestion of both donor and acceptor DNA molecules resulted in NHEJ-mediated replacement of the gfp with hpt and recovery of hygromycin-resistant plants that no longer expressed GFP and in which the hpt gene was physically linked to the acceptor DNA. Sequence and phenotypical analyses, and transmission of the replacement events to the next generation, confirmed the stability of the NHEJ-induced gene exchange, suggesting its use as a novel method for transgene replacement and gene stacking in plants.
Collapse
Affiliation(s)
- Dan Michael Weinthal
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109 (D.M.W., R.A.T., T.T.); and
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva 84105, Israel (D.M.W., T.T.)
| | - Roslyn Ann Taylor
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109 (D.M.W., R.A.T., T.T.); and
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva 84105, Israel (D.M.W., T.T.)
| | | |
Collapse
|
40
|
Yeast competence for exogenous DNA uptake: towards understanding its genetic component. Antonie van Leeuwenhoek 2013; 103:1181-207. [DOI: 10.1007/s10482-013-9905-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 03/14/2013] [Indexed: 12/20/2022]
|
41
|
Cools HJ, Hammond-Kosack KE. Exploitation of genomics in fungicide research: current status and future perspectives. MOLECULAR PLANT PATHOLOGY 2013; 14:197-210. [PMID: 23157348 PMCID: PMC6638899 DOI: 10.1111/mpp.12001] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Every year, fungicide use to control plant disease caused by pathogenic fungi increases. The global fungicide market is now worth more than £5.3 billion, second only to the herbicide market in importance. In the UK, over 5500 tonnes of fungicide were applied to crops in 2010 (The Food and Environment Research Agency, Pesticide Usage Statistics), with 95.5% of the wheat-growing area receiving three fungicide sprays. Although dependence on fungicides to produce food securely, reliably and cheaply may be moderated in the future by further developments in crop biotechnology, modern crop protection will continue to require a diversity of solutions, including effective and safe chemical control. Therefore, investment in exploiting the increasingly available genome sequences of the most devastating fungal and oomycete phytopathogenic species should bring an array of new opportunities for chemical intervention. To date, the impact of whole genome research on the development, introduction and stewardship of fungicides has been limited, but ongoing improvements in computational analysis, molecular biology, chemical genetics, genome sequencing and transcriptomics will facilitate the development and registration of the future suite of crop protection chemicals.
Collapse
Affiliation(s)
- Hans J Cools
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK.
| | | |
Collapse
|
42
|
Lacroix B, Citovsky V. The roles of bacterial and host plant factors in Agrobacterium-mediated genetic transformation. THE INTERNATIONAL JOURNAL OF DEVELOPMENTAL BIOLOGY 2013. [PMID: 24166430 DOI: 10.1387/ijdb.130199b1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The genetic transformation of plants mediated by Agrobacterium tumefaciens represents an essential tool for both fundamental and applied research in plant biology. For a successful infection, culminating in the integration of its transferred DNA (T-DNA) into the host genome, Agrobacterium relies on multiple interactions with host-plant factors. Extensive studies have unraveled many of such interactions at all major steps of the infection process: activation of the bacterial virulence genes, cell-cell contact and macromolecular translocation from Agrobacterium to host cell cytoplasm, intracellular transit of T-DNA and associated proteins (T-complex) to the host cell nucleus, disassembly of the T-complex, T-DNA integration, and expression of the transferred genes. During all these processes, Agrobacterium has evolved to control and even utilize several pathways of host-plant defense response. Studies of these Agrobacterium-host interactions substantially enhance our understanding of many fundamental cellular biological processes and allow improvements in the use of Agrobacterium as a gene transfer tool for biotechnology.
Collapse
Affiliation(s)
- Benoît Lacroix
- Department of Biochemistry and Cell Biology, State University of New York, Stony Brook, NY, USA.
| | | |
Collapse
|
43
|
Da Ines O, White CI. Gene Site-Specific Insertion in Plants. SITE-DIRECTED INSERTION OF TRANSGENES 2013. [DOI: 10.1007/978-94-007-4531-5_11] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
|
44
|
Kemski MM, Stevens B, Rappleye CA. Spectrum of T-DNA integrations for insertional mutagenesis of Histoplasma capsulatum. Fungal Biol 2012; 117:41-51. [PMID: 23332832 DOI: 10.1016/j.funbio.2012.11.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 11/15/2012] [Accepted: 11/19/2012] [Indexed: 10/27/2022]
Abstract
Agrobacterium-mediated transformation is being increasingly used for insertional mutagenesis of fungi. To better evaluate its effectiveness as a mutagen for the fungal pathogen Histoplasma capsulatum, we analyzed a collection of randomly selected T-DNA insertion mutants. Testing of different T-DNA element vectors engineered for transformation of fungi showed that pBHt2 provides the highest transformation efficiency and the lowest rate of vector backbone carryover. Sixty-eight individual T-DNA integrations were characterized by recovery of T-DNA ends and flanking genomic sequences. The right border (RB) end of the T-DNA is largely preserved whereas the left border (LB) end is frequently truncated. Analysis of T-DNA insertion sites confirms the lack of any integration hotspots in the Histoplasma genome. Relative to genes, T-DNA integrations show significant bias towards promoter regions at the expense of coding sequences. With consideration for potential promoter interruption and the demonstrated efficacy of intronic insertions, 61 % of mapped T-DNA insertions should impair gene expression or function. Mapping of T-DNA flanking sequences demonstrates 67 % of T-DNA integrations are integrations at a single chromosomal site and 31 % of T-DNA integrations are associated with large-scale chromosomal rearrangements. This characterization of T-DNA insertions in mutants selected without regard to phenotype supports application of Agrobacterium-mediated transformation as an insertional mutagen for genome-based screens and functional discovery of genes in Histoplasma.
Collapse
Affiliation(s)
- Megan M Kemski
- Department of Microbiology, Ohio State University, Columbus, OH 43210, USA
| | | | | |
Collapse
|
45
|
Saika H, Nonaka S, Osakabe K, Toki S. Sequential monitoring of transgene expression following Agrobacterium-mediated transformation of rice. PLANT & CELL PHYSIOLOGY 2012; 53:1974-83. [PMID: 23026817 DOI: 10.1093/pcp/pcs135] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Although Agrobacterium-mediated transformation technology is now used widely in rice, many varieties of indica-type rice are still recalcitrant to Agrobacterium-mediated transformation. It was reported recently that T-DNA integration into the rice genome could be the limiting step in this method. Here, we attempted to establish an efficient sequential monitoring system for stable transformation events by visualizing stable transgene expression using a non-destructive and highly sensitive visible marker. Our results demonstrate that click beetle luciferase (ELuc) is an excellent marker allowing the observation of transformed cells in rice callus, exhibiting a sensitivity >30-fold higher than that of firefly luciferase. Since we have previously shown that green fluorescent protein (GFP) is a useful visual marker with which to follow transient and/or stable expression of transgenes in rice, we constructed an enhancer trap vector using both the gfbsd2 (GFP fused to the N-terminus of blasticidin S deaminase) and eluc genes. In this vector, the eluc gene is under the control of the Cauliflower mosaic virus 35S minimal promoter, while the gfbsd2 gene is under the control of the full-length rice elongation factor gene promoter. Observation of transformed callus under a dissecting microscope demonstrated that the level of ELuc luminescence reflected exclusively stable transgene expression, and that both transient and stable expression could be monitored by the level of GFP fluorescence. Moreover, we show that our system enables sequential quantification of transgene expression via differential measurement of ELuc luminescence and GFP fluorescence.
Collapse
Affiliation(s)
- Hiroaki Saika
- Plant Genome Engineering Research Unit, Agrogenomics Research Center, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba, Ibaraki, 305-8602 Japan
| | | | | | | |
Collapse
|
46
|
Vaghchhipawala ZE, Vasudevan B, Lee S, Morsy MR, Mysore KS. Agrobacterium may delay plant nonhomologous end-joining DNA repair via XRCC4 to favor T-DNA integration. THE PLANT CELL 2012; 24:4110-23. [PMID: 23064322 PMCID: PMC3517239 DOI: 10.1105/tpc.112.100495] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Revised: 08/31/2012] [Accepted: 09/20/2012] [Indexed: 05/05/2023]
Abstract
Agrobacterium tumefaciens is a soilborne pathogen that causes crown gall disease in many dicotyledonous plants by transfer of a portion of its tumor-inducing plasmid (T-DNA) into the plant genome. Several plant factors that play a role in Agrobacterium attachment to plant cells and transport of T-DNA to the nucleus have been identified, but the T-DNA integration step during transformation is poorly understood and has been proposed to occur via nonhomologous end-joining (NHEJ)-mediated double-strand DNA break (DSB) repair. Here, we report a negative role of X-ray cross complementation group4 (XRCC4), one of the key proteins required for NHEJ, in Agrobacterium T-DNA integration. Downregulation of XRCC4 in Arabidopsis and Nicotiana benthamiana increased stable transformation due to increased T-DNA integration. Overexpression of XRCC4 in Arabidopsis decreased stable transformation due to decreased T-DNA integration. Interestingly, XRCC4 directly interacted with Agrobacterium protein VirE2 in a yeast two-hybrid system and in planta. VirE2-expressing Arabidopsis plants were more susceptible to the DNA damaging chemical bleomycin and showed increased stable transformation. We hypothesize that VirE2 titrates or excludes active XRCC4 protein available for DSB repair, thus delaying the closure of DSBs in the chromosome, providing greater opportunity for T-DNA to integrate.
Collapse
Affiliation(s)
| | - Balaji Vasudevan
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401
| | - Seonghee Lee
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401
| | | | - Kirankumar S. Mysore
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401
| |
Collapse
|
47
|
Agrobacterium tumefaciens T-DNA Integration and Gene Targeting in Arabidopsis thaliana Non-Homologous End-Joining Mutants. ACTA ACUST UNITED AC 2012. [DOI: 10.1155/2012/989272] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In order to study the role of AtKu70 and AtKu80 in Agrobacterium-mediated transformation and gene targeting, plant lines with a T-DNA insertion in AtKu80 or AtKu70 genes were functionally characterized. Such plant lines lacked both subunits, indicating that heterodimer formation between AtKu70 and AtKu80 is needed for the stability of the proteins. Homozygous mutants were phenotypically indistinguishable from wild-type plants and were fertile. However, they were hypersensitive to the genotoxic agent bleomycin, resulting in more DSBs as quantified in comet assays. They had lower end-joining efficiency, suggesting that NHEJ is a critical pathway for DSB repair in plants. Both Atku mutants and a previously isolated Atmre11 mutant were impaired in Agrobacterium T-DNA integration via floral dip transformation, indicating that AtKu70, AtKu80, and AtMre11 play an important role in T-DNA integration in Arabidopsis. The frequency of gene targeting was not significantly increased in the Atku80 and Atku70 mutants, but it was increased at least 10-fold in the Atmre11 mutant compared with the wild type.
Collapse
|
48
|
Tie W, Zhou F, Wang L, Xie W, Chen H, Li X, Lin Y. Reasons for lower transformation efficiency in indica rice using Agrobacterium tumefaciens-mediated transformation: lessons from transformation assays and genome-wide expression profiling. PLANT MOLECULAR BIOLOGY 2012; 78:1-18. [PMID: 22089972 DOI: 10.1007/s11103-011-9842-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Accepted: 09/24/2011] [Indexed: 05/22/2023]
Abstract
Agrobacterium tumefaciens-mediated genetic transformation has been routinely used in rice for more than a decade. However, the transformation efficiency of the indica rice variety is still unsatisfactory and much lower than that of japonica cultivars. Further improvement on the transformation efficiency lies in the genetic manipulation of the plant itself, which requires a better understanding of the underlying process accounting for the susceptibility of plant cells to Agrobacterium infection as well as the identification of plant genes involved in the transformation process. In this study, transient and stable transformation assays using different japonica and indica cultivars showed that the lower transformation efficiency in indica rice was mainly due to the low efficiency in T-DNA integration into the plant genome. Analyses of the global gene expression patterns across the transformation process in different varieties revealed major differences in the expression of genes responding to Agrobacterium within the first 6 h after infection and more differentially expressed genes were observed in the indica cultivar Zhenshan 97 (ZS), with a number of genes repressed early during infection. Microarray analysis revealed an important effect of plant defense response on Agrobacterium-mediated transformation. It has been shown that some genes which may be necessary for the transformation process were down-regulated in the indica cultivar ZS. This dataset provided a versatile resource for plant genomic research to understand the regulatory network of transformation process, and showed great promise for improving indica rice transformation using genetic manipulation of the rice genome.
Collapse
Affiliation(s)
- Weiwei Tie
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan, China
| | | | | | | | | | | | | |
Collapse
|
49
|
Kamisugi Y, Schaefer DG, Kozak J, Charlot F, Vrielynck N, Holá M, Angelis KJ, Cuming AC, Nogué F. MRE11 and RAD50, but not NBS1, are essential for gene targeting in the moss Physcomitrella patens. Nucleic Acids Res 2011; 40:3496-510. [PMID: 22210882 PMCID: PMC3333855 DOI: 10.1093/nar/gkr1272] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The moss Physcomitrella patens is unique among plant models for the high frequency with which targeted transgene insertion occurs via homologous recombination. Transgene integration is believed to utilize existing machinery for the detection and repair of DNA double-strand breaks (DSBs). We undertook targeted knockout of the Physcomitrella genes encoding components of the principal sensor of DNA DSBs, the MRN complex. Loss of function of PpMRE11 or PpRAD50 strongly and specifically inhibited gene targeting, whilst rates of untargeted transgene integration were relatively unaffected. In contrast, disruption of the PpNBS1 gene retained the wild-type capacity to integrate transforming DNA efficiently at homologous loci. Analysis of the kinetics of DNA-DSB repair in wild-type and mutant plants by single-nucleus agarose gel electrophoresis revealed that bleomycin-induced fragmentation of genomic DNA was repaired at approximately equal rates in each genotype, although both the Ppmre11 and Pprad50 mutants exhibited severely restricted growth and development and enhanced sensitivity to UV-B and bleomycin-induced DNA damage, compared with wild-type and Ppnbs1 plants. This implies that while extensive DNA repair can occur in the absence of a functional MRN complex; this is unsupervised in nature and results in the accumulation of deleterious mutations incompatible with normal growth and development.
Collapse
Affiliation(s)
- Yasuko Kamisugi
- Centre for Plant Sciences, Faculty of Biological Sciences, Leeds University, Leeds LS2 9JT, UK
| | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Frandsen RJN. A guide to binary vectors and strategies for targeted genome modification in fungi using Agrobacterium tumefaciens-mediated transformation. J Microbiol Methods 2011; 87:247-62. [DOI: 10.1016/j.mimet.2011.09.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Revised: 09/09/2011] [Accepted: 09/09/2011] [Indexed: 01/31/2023]
|