1
|
Raabe K, Sun L, Schindfessel C, Honys D, Geelen D. A word of caution: T-DNA-associated mutagenesis in plant reproduction research. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:3248-3258. [PMID: 38477707 DOI: 10.1093/jxb/erae114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Accepted: 03/12/2024] [Indexed: 03/14/2024]
Abstract
T-DNA transformation is prevalent in Arabidopsis research and has expanded to a broad range of crops and model plants. While major progress has been made in optimizing the Agrobacterium-mediated transformation process for various species, a variety of pitfalls associated with the T-DNA insertion may lead to the misinterpretation of T-DNA mutant analysis. Indeed, secondary mutagenesis either on the integration site or elsewhere in the genome, together with epigenetic interactions between T-DNA inserts or frequent genomic rearrangements, can be tricky to differentiate from the effect of the knockout of the gene of interest. These are mainly the case for genomic rearrangements that become balanced in filial generations without consequential phenotypical defects, which may be confusing particularly for studies that aim to investigate fertility and gametogenesis. As a cautionary note to the plant research community studying gametogenesis, we here report an overview of the consequences of T-DNA-induced secondary mutagenesis with emphasis on the genomic imbalance on gametogenesis. Additionally, we present a simple guideline to evaluate the T-DNA-mutagenized transgenic lines to decrease the risk of faulty analysis with minimal experimental effort.
Collapse
Affiliation(s)
- Karel Raabe
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Prague 6, Czech Republic
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 128 44 Prague 2, Czech Republic
| | - Limin Sun
- Horticell, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Cédric Schindfessel
- Horticell, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - David Honys
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Prague 6, Czech Republic
| | - Danny Geelen
- Horticell, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| |
Collapse
|
2
|
Thomson G, Dickinson L, Jacob Y. Genomic consequences associated with Agrobacterium-mediated transformation of plants. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 117:342-363. [PMID: 37831618 PMCID: PMC10841553 DOI: 10.1111/tpj.16496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 09/22/2023] [Accepted: 09/27/2023] [Indexed: 10/15/2023]
Abstract
Attenuated strains of the naturally occurring plant pathogen Agrobacterium tumefaciens can transfer virtually any DNA sequence of interest to model plants and crops. This has made Agrobacterium-mediated transformation (AMT) one of the most commonly used tools in agricultural biotechnology. Understanding AMT, and its functional consequences, is of fundamental importance given that it sits at the intersection of many fundamental fields of study, including plant-microbe interactions, DNA repair/genome stability, and epigenetic regulation of gene expression. Despite extensive research and use of AMT over the last 40 years, the extent of genomic disruption associated with integrating exogenous DNA into plant genomes using this method remains underappreciated. However, new technologies like long-read sequencing make this disruption more apparent, complementing previous findings from multiple research groups that have tackled this question in the past. In this review, we cover progress on the molecular mechanisms involved in Agrobacterium-mediated DNA integration into plant genomes. We also discuss localized mutations at the site of insertion and describe the structure of these DNA insertions, which can range from single copy insertions to large concatemers, consisting of complex DNA originating from different sources. Finally, we discuss the prevalence of large-scale genomic rearrangements associated with the integration of DNA during AMT with examples. Understanding the intended and unintended effects of AMT on genome stability is critical to all plant researchers who use this methodology to generate new genetic variants.
Collapse
Affiliation(s)
- Geoffrey Thomson
- Yale University, Department of Molecular, Cellular and Developmental Biology, Faculty of Arts and Sciences; New Haven, Connecticut 06511, USA
| | - Lauren Dickinson
- Yale University, Department of Molecular, Cellular and Developmental Biology, Faculty of Arts and Sciences; New Haven, Connecticut 06511, USA
| | - Yannick Jacob
- Yale University, Department of Molecular, Cellular and Developmental Biology, Faculty of Arts and Sciences; New Haven, Connecticut 06511, USA
- Yale Cancer Center, Yale School of Medicine; New Haven, Connecticut 06511, USA
| |
Collapse
|
3
|
Nishizawa‐Yokoi A, Gelvin SB. Transformation and regeneration of DNA polymerase Θ mutant rice plants. PLANT DIRECT 2023; 7:e526. [PMID: 37681196 PMCID: PMC10480422 DOI: 10.1002/pld3.526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 08/05/2023] [Accepted: 08/09/2023] [Indexed: 09/09/2023]
Abstract
Agrobacterium T-DNA integration into the plant genome is essential for the process of transgenesis and is widely used for genome engineering. The importance of the non-homologous end-joining (NHEJ) protein DNA polymerase Θ, encoded by the PolQ gene, for T-DNA integration is controversial, with some groups claiming it is essential whereas others claim T-DNA integration in Arabidopsis and rice polQ mutant plant tissue. Because of pleiotropic effects of PolQ loss on plant development, scientists have previously had difficulty regenerating transgenic polQ mutant plants. We describe a protocol for regenerating transgenic polQ mutant rice plants using a sequential transformation method. This protocol may be applicable to other plant species.
Collapse
Affiliation(s)
- Ayako Nishizawa‐Yokoi
- Institute of Agrobiological SciencesNational Agriculture and Food Research OrganizationTsukubaJapan
| | - Stanton B. Gelvin
- Department of Biological SciencesPurdue UniversityWest LafayetteIndianaUSA
| |
Collapse
|
4
|
Singer K, Lee LY, Yuan J, Gelvin SB. Characterization of T-Circles and Their Formation Reveal Similarities to Agrobacterium T-DNA Integration Patterns. FRONTIERS IN PLANT SCIENCE 2022; 13:849930. [PMID: 35599900 PMCID: PMC9121065 DOI: 10.3389/fpls.2022.849930] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 03/29/2022] [Indexed: 06/15/2023]
Abstract
Agrobacterium transfers T-DNA to plants where it may integrate into the genome. Non-homologous end-joining (NHEJ) has been invoked as the mechanism of T-DNA integration, but the role of various NHEJ proteins remains controversial. Genetic evidence for the role of NHEJ in T-DNA integration has yielded conflicting results. We propose to investigate the formation of T-circles as a proxy for understanding T-DNA integration. T-circles are circular double-strand T-DNA molecules, joined at their left (LB) and right (RB) border regions, formed in plants. We characterized LB-RB junction regions from hundreds of T-circles formed in Nicotiana benthamiana or Arabidopsis thaliana. These junctions resembled T-DNA/plant DNA junctions found in integrated T-DNA: Among complex T-circles composed of multiple T-DNA molecules, RB-RB/LB-LB junctions predominated over RB-LB junctions; deletions at the LB were more frequent and extensive than those at the RB; microhomology was frequently used at junction sites; and filler DNA, from the plant genome or various Agrobacterium replicons, was often present between the borders. Ku80 was not required for efficient T-circle formation, and a VirD2 ω mutation affected T-circle formation and T-DNA integration similarly. We suggest that investigating the formation of T-circles may serve as a surrogate for understanding T-DNA integration.
Collapse
|
5
|
Dash M, Somvanshi VS, Godwin J, Budhwar R, Sreevathsa R, Rao U. Exploring Genomic Variations in Nematode-Resistant Mutant Rice Lines. FRONTIERS IN PLANT SCIENCE 2022; 13:823372. [PMID: 35401589 PMCID: PMC8988285 DOI: 10.3389/fpls.2022.823372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Accepted: 02/28/2022] [Indexed: 06/14/2023]
Abstract
Rice (Oryza sativa) production is seriously affected by the root-knot nematode Meloidogyne graminicola, which has emerged as a menace in upland and irrigated rice cultivation systems. Previously, activation tagging in rice was utilized to identify candidate gene(s) conferring resistance against M. graminicola. T-DNA insertional mutants were developed in a rice landrace (acc. JBT 36/14), and four mutant lines showed nematode resistance. Whole-genome sequencing of JBT 36/14 was done along with the four nematode resistance mutant lines to identify the structural genetic variations that might be contributing to M. graminicola resistance. Sequencing on Illumina NovaSeq 6000 platform identified 482,234 genetic variations in JBT 36/14 including 448,989 SNPs and 33,245 InDels compared to reference indica genome. In addition, 293,238-553,648 unique SNPs and 32,395-65,572 unique InDels were found in the four mutant lines compared to their JBT 36/14 background, of which 93,224 SNPs and 8,170 InDels were common between all the mutant lines. Functional annotation of genes containing these structural variations showed that the majority of them were involved in metabolism and growth. Trait analysis revealed that most of these genes were involved in morphological traits, physiological traits and stress resistance. Additionally, several families of transcription factors, such as FAR1, bHLH, and NAC, and putative susceptibility (S) genes, showed the presence of SNPs and InDels. Our results indicate that subject to further genetic validations, these structural genetic variations may be involved in conferring nematode resistance to the rice mutant lines.
Collapse
Affiliation(s)
- Manoranjan Dash
- Division of Nematology, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | | | | | - Roli Budhwar
- Bionivid Technology Private Limited, Bangalore, India
| | | | - Uma Rao
- Division of Nematology, ICAR-Indian Agricultural Research Institute, New Delhi, India
| |
Collapse
|
6
|
Gong W, Zhou Y, Wang R, Wei X, Zhang L, Dai Y, Zhu Z. Analysis of T-DNA integration events in transgenic rice. JOURNAL OF PLANT PHYSIOLOGY 2021; 266:153527. [PMID: 34563791 DOI: 10.1016/j.jplph.2021.153527] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 09/13/2021] [Accepted: 09/13/2021] [Indexed: 06/13/2023]
Abstract
Agrobacterium-mediated plant transformation has been widely used for introducing transgene(s) into a plant genome and plant breeding. However, our understanding of T-DNA integration into rice genome remains limited relative to that in the model dicot Arabidopsis. To better elucidate the T-DNA integration into the rice genome, we investigated extensively the T-DNA ends and their flanking rice genomic sequences from two transgenic rice plants carrying Cowpea Trypsin Inhibitor (CpTI)-derived gene Signal-CpTI-KDEL (SCK) and Bacillus thuringiensis (BT) gene, respectively, by TAIL-PCR method. Analysis of the junction sequences between the T-DNA ends and rice genome DNA indicated that there were three joining patterns of microhomology, filler DNA sequences, and exact joining, and both the T-DNA ends tend to adopt identical manner to join the rice genome. After T-DNA integration, there were several variations of rice genomic sequences, including small deletions at the integration sites, superfluous DNA inserted between T-DNA and genome, and translocation of genomic DNA in the flanking regions. The translocation block could be from a noncontiguous region in the same chromosome or different chromosomes at the integration sites, and the originating position of the translocated block resulted in comparable deletion based on a cut/paste mechanism rather than a replication mechanism. Our study may lead to a better understand of T-DNA integration mechanism and facilitate functional genomic studies and further crop improvement.
Collapse
Affiliation(s)
- Wankui Gong
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China; State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, 455000, China.
| | - Yun Zhou
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Rui Wang
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China; Public Health Emergency Center, Chinese Center for Disease Control and Prevention, Beijing, 102206, China.
| | - Xiaoli Wei
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Lei Zhang
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Yan Dai
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Zhen Zhu
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.
| |
Collapse
|
7
|
Plant DNA Repair and Agrobacterium T-DNA Integration. Int J Mol Sci 2021; 22:ijms22168458. [PMID: 34445162 PMCID: PMC8395108 DOI: 10.3390/ijms22168458] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 08/02/2021] [Accepted: 08/03/2021] [Indexed: 12/28/2022] Open
Abstract
Agrobacterium species transfer DNA (T-DNA) to plant cells where it may integrate into plant chromosomes. The process of integration is thought to involve invasion and ligation of T-DNA, or its copying, into nicks or breaks in the host genome. Integrated T-DNA often contains, at its junctions with plant DNA, deletions of T-DNA or plant DNA, filler DNA, and/or microhomology between T-DNA and plant DNA pre-integration sites. T-DNA integration is also often associated with major plant genome rearrangements, including inversions and translocations. These characteristics are similar to those often found after repair of DNA breaks, and thus DNA repair mechanisms have frequently been invoked to explain the mechanism of T-DNA integration. However, the involvement of specific plant DNA repair proteins and Agrobacterium proteins in integration remains controversial, with numerous contradictory results reported in the literature. In this review I discuss this literature and comment on many of these studies. I conclude that either multiple known DNA repair pathways can be used for integration, or that some yet unknown pathway must exist to facilitate T-DNA integration into the plant genome.
Collapse
|
8
|
Pucker B, Kleinbölting N, Weisshaar B. Large scale genomic rearrangements in selected Arabidopsis thaliana T-DNA lines are caused by T-DNA insertion mutagenesis. BMC Genomics 2021; 22:599. [PMID: 34362298 PMCID: PMC8348815 DOI: 10.1186/s12864-021-07877-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Accepted: 07/06/2021] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Experimental proof of gene function assignments in plants is based on mutant analyses. T-DNA insertion lines provided an invaluable resource of mutants and enabled systematic reverse genetics-based investigation of the functions of Arabidopsis thaliana genes during the last decades. RESULTS We sequenced the genomes of 14 A. thaliana GABI-Kat T-DNA insertion lines, which eluded flanking sequence tag-based attempts to characterize their insertion loci, with Oxford Nanopore Technologies (ONT) long reads. Complex T-DNA insertions were resolved and 11 previously unknown T-DNA loci identified, resulting in about 2 T-DNA insertions per line and suggesting that this number was previously underestimated. T-DNA mutagenesis caused fusions of chromosomes along with compensating translocations to keep the gene set complete throughout meiosis. Also, an inverted duplication of 800 kbp was detected. About 10 % of GABI-Kat lines might be affected by chromosomal rearrangements, some of which do not involve T-DNA. Local assembly of selected reads was shown to be a computationally effective method to resolve the structure of T-DNA insertion loci. We developed an automated workflow to support investigation of long read data from T-DNA insertion lines. All steps from DNA extraction to assembly of T-DNA loci can be completed within days. CONCLUSIONS Long read sequencing was demonstrated to be an effective way to resolve complex T-DNA insertions and chromosome fusions. Many T-DNA insertions comprise not just a single T-DNA, but complex arrays of multiple T-DNAs. It is becoming obvious that T-DNA insertion alleles must be characterized by exact identification of both T-DNA::genome junctions to generate clear genotype-to-phenotype relations.
Collapse
Affiliation(s)
- Boas Pucker
- Genetics and Genomics of Plants, Center for Biotechnology (CeBiTec), Bielefeld University, Sequenz 1, 33615 Bielefeld, Germany
- Evolution and Diversity, Department of Plant Sciences, University of Cambridge, Cambridge, UK
| | - Nils Kleinbölting
- Bioinformatics Resource Facility, Center for Biotechnology (CeBiTec, Bielefeld University, Sequenz 1, 33615 Bielefeld, Germany
| | - Bernd Weisshaar
- Genetics and Genomics of Plants, Center for Biotechnology (CeBiTec), Bielefeld University, Sequenz 1, 33615 Bielefeld, Germany
| |
Collapse
|
9
|
Chen X, Dong Y, Huang Y, Fan J, Yang M, Zhang J. Whole-genome resequencing using next-generation and Nanopore sequencing for molecular characterization of T-DNA integration in transgenic poplar 741. BMC Genomics 2021; 22:329. [PMID: 33957867 PMCID: PMC8101135 DOI: 10.1186/s12864-021-07625-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 04/16/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The molecular characterization information of T-DNA integration is not only required by public risk assessors and regulators, but is also closely related to the expression of exogenous and endogenous genes. At present, with the development of sequencing technology, whole-genome resequencing has become an attractive approach to identify unknown genetically modified events and characterise T-DNA integration events. RESULTS In this study, we performed genome resequencing of Pb29, a transgenic high-resistance poplar 741 line that has been commercialized, using next-generation and Nanopore sequencing. The results revealed that there are two T-DNA insertion sites, located at 9,283,905-9,283,937 bp on chromosome 3 (Chr03) and 10,868,777-10,868,803 bp on Chr10. The accuracy of the T-DNA insertion locations and directions was verified using polymerase chain reaction amplification. Through sequence alignment, different degrees of base deletions were detected on the T-DNA left and right border sequences, and in the flanking sequences of the insertion sites. An unknown fragment was inserted between the Chr03 insertion site and the right flanking sequence, but the Pb29 genome did not undergo chromosomal rearrangement. It is worth noting that we did not detect the API gene in the Pb29 genome, indicating that Pb29 is a transgenic line containing only the BtCry1AC gene. On Chr03, the insertion of T-DNA disrupted a gene encoding TAF12 protein, but the transcriptional abundance of this gene did not change significantly in the leaves of Pb29. Additionally, except for the gene located closest to the T-DNA integration site, the expression levels of four other neighboring genes did not change significantly in the leaves of Pb29. CONCLUSIONS This study provides molecular characterization information of T-DNA integration in transgenic poplar 741 line Pb29, which contribute to safety supervision and further extensive commercial planting of transgenic poplar 741.
Collapse
Affiliation(s)
- Xinghao Chen
- Forest Department, Forestry College, Hebei Agricultural University, Baoding, China.,Hebei Key Laboratory for Tree Genetic Resources and Forest Protection, 071000, Baoding, PR China
| | - Yan Dong
- Forest Department, Forestry College, Hebei Agricultural University, Baoding, China.,Hebei Key Laboratory for Tree Genetic Resources and Forest Protection, 071000, Baoding, PR China
| | - Yali Huang
- Forest Department, Forestry College, Hebei Agricultural University, Baoding, China.,Hebei Key Laboratory for Tree Genetic Resources and Forest Protection, 071000, Baoding, PR China
| | - Jianmin Fan
- Forest Department, Forestry College, Hebei Agricultural University, Baoding, China.,Hebei Key Laboratory for Tree Genetic Resources and Forest Protection, 071000, Baoding, PR China
| | - Minsheng Yang
- Forest Department, Forestry College, Hebei Agricultural University, Baoding, China. .,Hebei Key Laboratory for Tree Genetic Resources and Forest Protection, 071000, Baoding, PR China.
| | - Jun Zhang
- Forest Department, Forestry College, Hebei Agricultural University, Baoding, China. .,Hebei Key Laboratory for Tree Genetic Resources and Forest Protection, 071000, Baoding, PR China.
| |
Collapse
|
10
|
Sankaranarayanan S, Jamshed M, Delmas F, Yeung EC, Samuel MA. Identification and characterization of a female gametophyte defect in sdk1-7 +/- abi3-6 +/- heterozygotes of Arabidopsis thaliana. PLANT SIGNALING & BEHAVIOR 2020; 15:1780038. [PMID: 32657242 PMCID: PMC8570737 DOI: 10.1080/15592324.2020.1780038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/18/2020] [Accepted: 05/19/2020] [Indexed: 06/11/2023]
Abstract
Successful reproduction in angiosperms is dependent on the highly synchronous development of their male and female gametophytes and the ensuing fusion of the gametes from these reproductive tissue types. When crossing a T-DNA insertion line sdk1-7-/-(Salk_024564), one of the S-domain receptor kinases involved in ABA responses with a fast neutron deletion line abi3-6-/-, the F1 heterozygotes (sdk1-7+/-abi3-6 +/-) displayed 50% ovule abortion suggesting a likely gametophytic defects. We identified and characterized an early stage female gametophyte developmental defect in the heterozygous mutant ovules. Recombination frequency analysis of the F2 progenies from selfed heterozygotes revealed a possible pseudo-linkage of sdk1-7 and abi3-6 suggesting a reciprocal translocation event in the heterozygote. Our study emphasizes the importance of robust analysis to distinguish gametophytic defect phenotypes caused by genetic interactions and that resulting from possible chromosomal translocation events.
Collapse
Affiliation(s)
- Subramanian Sankaranarayanan
- Department of Biological Sciences, BI 392, University of Calgary, Calgary, Alberta, Canada
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, USA
| | - Muhammad Jamshed
- Department of Biological Sciences, BI 392, University of Calgary, Calgary, Alberta, Canada
- Frontier Agri-Science, Port Hope, Ontario, Canada
| | - Frédéric Delmas
- UMR1332 BFP, INRAE, Université De Bordeaux, Villenave d’Ornon, France
| | - Edward C. Yeung
- Department of Biological Sciences, BI 392, University of Calgary, Calgary, Alberta, Canada
| | - Marcus A. Samuel
- Department of Biological Sciences, BI 392, University of Calgary, Calgary, Alberta, Canada
| |
Collapse
|
11
|
Hoffmann RD, Portes MT, Olsen LI, Damineli DSC, Hayashi M, Nunes CO, Pedersen JT, Lima PT, Campos C, Feijó JA, Palmgren M. Plasma membrane H +-ATPases sustain pollen tube growth and fertilization. Nat Commun 2020; 11:2395. [PMID: 32409656 PMCID: PMC7224221 DOI: 10.1038/s41467-020-16253-1] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 04/23/2020] [Indexed: 01/18/2023] Open
Abstract
Pollen tubes are highly polarized tip-growing cells that depend on cytosolic pH gradients for signaling and growth. Autoinhibited plasma membrane proton (H+) ATPases (AHAs) have been proposed to energize pollen tube growth and underlie cell polarity, however, mechanistic evidence for this is lacking. Here we report that the combined loss of AHA6, AHA8, and AHA9 in Arabidopsis thaliana delays pollen germination and causes pollen tube growth defects, leading to drastically reduced fertility. Pollen tubes of aha mutants had reduced extracellular proton (H+) and anion fluxes, reduced cytosolic pH, reduced tip-to-shank proton gradients, and defects in actin organization. Furthermore, mutant pollen tubes had less negative membrane potentials, substantiating a mechanistic role for AHAs in pollen tube growth through plasma membrane hyperpolarization. Our findings define AHAs as energy transducers that sustain the ionic circuit defining the spatial and temporal profiles of cytosolic pH, thereby controlling downstream pH-dependent mechanisms essential for pollen tube elongation, and thus plant fertility.
Collapse
Affiliation(s)
- Robert D Hoffmann
- Department for Plant and Environmental Sciences, University of Copenhagen, 1871, Frederiksberg C, Denmark
| | - Maria Teresa Portes
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, 20742, USA
| | - Lene Irene Olsen
- Department for Plant and Environmental Sciences, University of Copenhagen, 1871, Frederiksberg C, Denmark
| | - Daniel Santa Cruz Damineli
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, 20742, USA
- Department of Pediatrics, Faculdade de Medicina da Universidade de São Paulo, São Paulo, SP, 01246-903, Brazil
| | - Maki Hayashi
- Department for Plant and Environmental Sciences, University of Copenhagen, 1871, Frederiksberg C, Denmark
| | - Custódio O Nunes
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, 20742, USA
| | - Jesper T Pedersen
- Department for Plant and Environmental Sciences, University of Copenhagen, 1871, Frederiksberg C, Denmark
| | - Pedro T Lima
- Instituto Gulbenkian de Ciência, Oeiras, 2780-156, Portugal
| | - Cláudia Campos
- Instituto Gulbenkian de Ciência, Oeiras, 2780-156, Portugal
| | - José A Feijó
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, 20742, USA.
- Instituto Gulbenkian de Ciência, Oeiras, 2780-156, Portugal.
| | - Michael Palmgren
- Department for Plant and Environmental Sciences, University of Copenhagen, 1871, Frederiksberg C, Denmark.
| |
Collapse
|
12
|
Gang H, Liu G, Zhang M, Zhao Y, Jiang J, Chen S. Comprehensive characterization of T-DNA integration induced chromosomal rearrangement in a birch T-DNA mutant. BMC Genomics 2019; 20:311. [PMID: 31014254 PMCID: PMC6480916 DOI: 10.1186/s12864-019-5636-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 03/24/2019] [Indexed: 11/29/2022] Open
Abstract
Background Integration of T-DNA into plant genomes via Agrobacterium may interrupt gene structure and generate numerous mutants. The T-DNA caused mutants are valuable materials for understanding T-DNA integration model in plant research. T-DNA integration in plants is complex and still largely unknown. In this work, we reported that multiple T-DNA fragments caused chromosomal translocation and deletion in a birch (Betula platyphylla × B. pendula) T-DNA mutant yl. Results We performed PacBio genome resequencing for yl and the result revealed that two ends of a T-DNA can be integrated into plant genome independently because the two ends can be linked to different chromosomes and cause chromosomal translocation. We also found that these T-DNA were connected into tandem fragment regardless of direction before integrating into plant genome. In addition, the integration of T-DNA in yl genome also caused several chromosomal fragments deletion. We then summarized three cases for T-DNA integration model in the yl genome. (1) A T-DNA fragment is linked to the two ends of a double-stranded break (DSB); (2) Only one end of a T-DNA fragment is linked to a DSB; (3) A T-DNA fragment is linked to the ends of different DSBs. All the observations in the yl genome supported the DSB repair model. Conclusions In this study, we showed a comprehensive genome analysis of a T-DNA mutant and provide a new insight into T-DNA integration in plants. These findings would be helpful for the analysis of T-DNA mutants with special phenotypes. Electronic supplementary material The online version of this article (10.1186/s12864-019-5636-y) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Huixin Gang
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, 26 Hexing Road, Harbin, 150040, China
| | - Guifeng Liu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, 26 Hexing Road, Harbin, 150040, China
| | - Manman Zhang
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, 26 Hexing Road, Harbin, 150040, China
| | - Yuming Zhao
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, 26 Hexing Road, Harbin, 150040, China
| | - Jing Jiang
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, 26 Hexing Road, Harbin, 150040, China.
| | - Su Chen
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, 26 Hexing Road, Harbin, 150040, China.
| |
Collapse
|
13
|
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
|
14
|
Hu Y, Chen Z, Zhuang C, Huang J. Cascade of chromosomal rearrangements caused by a heterogeneous T-DNA integration supports the double-stranded break repair model for T-DNA integration. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 90:954-965. [PMID: 28244154 DOI: 10.1111/tpj.13523] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 02/15/2017] [Accepted: 02/20/2017] [Indexed: 06/06/2023]
Abstract
Transferred DNA (T-DNA) from Agrobacterium tumefaciens can be integrated into the plant genome. The double-stranded break repair (DSBR) pathway is a major model for T-DNA integration. From this model, we expect that two ends of a T-DNA molecule would invade into a single DNA double-stranded break (DSB) or independent DSBs in the plant genome. We call the later phenomenon a heterogeneous T-DNA integration, which has never been observed. In this work, we demonstrated it in an Arabidopsis T-DNA insertion mutant seb19. To resolve the chromosomal structural changes caused by T-DNA integration at both the nucleotide and chromosome levels, we performed inverse PCR, genome resequencing, fluorescence in situ hybridization and linkage analysis. We found, in seb19, a single T-DNA connected two different chromosomal loci and caused complex chromosomal rearrangements. The specific break-junction pattern in seb19 is consistent with the result of heterogeneous T-DNA integration but not of recombination between two T-DNA insertions. We demonstrated that, in seb19, heterogeneous T-DNA integration evoked a cascade of incorrect repair of seven DSBs on chromosomes 4 and 5, and then produced translocation, inversion, duplication and deletion. Heterogeneous T-DNA integration supports the DSBR model and suggests that two ends of a T-DNA molecule could be integrated into the plant genome independently. Our results also show a new origin of chromosomal abnormalities.
Collapse
Affiliation(s)
- Yufei Hu
- College of Life Sciences, South China Agricultural University, Guangzhou, 510642, China
| | - Zhiyu Chen
- College of Life Sciences, South China Agricultural University, Guangzhou, 510642, China
| | - Chuxiong Zhuang
- College of Life Sciences, South China Agricultural University, Guangzhou, 510642, China
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangzhou, 510642, China
| | - Jilei Huang
- Instrumental Analysis and Research Center, South China Agricultural University, Guangzhou, 510642, China
| |
Collapse
|
15
|
Hamann T. The plant cell wall integrity maintenance mechanism--a case study of a cell wall plasma membrane signaling network. PHYTOCHEMISTRY 2015; 112:100-9. [PMID: 25446233 DOI: 10.1016/j.phytochem.2014.09.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 09/07/2014] [Accepted: 09/23/2014] [Indexed: 05/18/2023]
Abstract
Some of the most important functions of plant cell walls are protection against biotic/abiotic stress and structural support during growth and development. A prerequisite for plant cell walls to perform these functions is the ability to perceive different types of stimuli in both qualitative and quantitative manners and initiate appropriate responses. The responses in turn involve adaptive changes in cellular and cell wall metabolism leading to modifications in the structures originally required for perception. While our knowledge about the underlying plant mechanisms is limited, results from Saccharomyces cerevisiae suggest the cell wall integrity maintenance mechanism represents an excellent example to illustrate how the molecular mechanisms responsible for stimulus perception, signal transduction and integration can function. Here I will review the available knowledge about the yeast cell wall integrity maintenance system for illustration purposes, summarize the limited knowledge available about the corresponding plant mechanism and discuss the relevance of the plant cell wall integrity maintenance mechanism in biotic stress responses.
Collapse
Affiliation(s)
- Thorsten Hamann
- Department of Biology, Høgskoleringen 5, Realfagbygget, Norwegian University of Science and Technology, 7491 Trondheim, Norway.
| |
Collapse
|