1
|
Nishihara M, Hirabuchi A, Goto F, Watanabe A, Yoshida C, Washiashi R, Odashima M, Nemoto K. Efficient double-flowered gentian plant production using the CRISPR/Cas9 system. PLANT BIOTECHNOLOGY (TOKYO, JAPAN) 2023; 40:229-236. [PMID: 38420567 PMCID: PMC10901158 DOI: 10.5511/plantbiotechnology.23.0424a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 04/24/2023] [Indexed: 03/02/2024]
Abstract
Japanese cultivated gentians are highly valued ornamental flowers in Japan, but the flower shape is mostly limited to the single-flower type, unlike other flowers such as roses and carnations. To overcome this limitation, we used the CRISPR/Cas9 genome editing system to increase double-flowered genetic resources in gentians. Our approach targeted an AGAMOUS (AG) floral homeotic gene (AG1), which is responsible for the natural mutation that causes double flowers in gentians. We designed two targets in exon 1 of AG1 for genome editing and found that 9 of 12 herbicide-resistant shoots had biallelic mutations in the target regions of AG1. These nine lines all produced double flowers, with stamens converted into petaloid organs, similar to the natural mutant. We also analyzed the off-target effects of AG2, which is homologous to AG1, and found that such effects occurred in gentian genome editing but with low frequency. Furthermore, we successfully produced transgene-free genome-edited plants (null segregants) by crossing with wild-type pollen. F1 seedlings were subjected to PCR analysis to determine whether foreign DNA sequences, two partial regions of the CaMV35S promoter and Cas9 gene, were present in the genome. As a result, foreign genes were segregated at a 1 : 1 ratio, indicating successful null segregant production. Using PCR analysis, we confirmed that four representative null segregants did not contain transfer DNA. In summary, our study demonstrates that the CRISPR/Cas9 system can efficiently produce double-flowered gentians, and null segregants can also be obtained. These genome-edited plants are valuable genetic resources for future gentian breeding programs.
Collapse
Affiliation(s)
- Masahiro Nishihara
- Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami, Iwate 024-0003, Japan
| | - Akiko Hirabuchi
- Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami, Iwate 024-0003, Japan
| | - Fumina Goto
- Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami, Iwate 024-0003, Japan
| | - Aiko Watanabe
- Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami, Iwate 024-0003, Japan
| | - Chiharu Yoshida
- Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami, Iwate 024-0003, Japan
| | - Rie Washiashi
- Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami, Iwate 024-0003, Japan
| | - Masashi Odashima
- Iwate Agricultural Research Center, 20-1 Narita, Kitakami, Iwate 024-0003, Japan
| | - Keiichirou Nemoto
- Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami, Iwate 024-0003, Japan
| |
Collapse
|
2
|
Tasaki K, Watanabe A, Nemoto K, Takahashi S, Goto F, Sasaki N, Hikage T, Nishihara M. Identification of Candidate Genes Responsible for Flower Colour Intensity in Gentiana triflora. FRONTIERS IN PLANT SCIENCE 2022; 13:906879. [PMID: 35812931 PMCID: PMC9257217 DOI: 10.3389/fpls.2022.906879] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 05/23/2022] [Indexed: 06/15/2023]
Abstract
Gentians cultivated in Japan (Gentiana triflora and Gentiana scabra and hybrids) have blue flowers, but flower colour intensity differs among cultivars. The molecular mechanism underlying the variation in flower colour intensity is unclear. Here, we produced F2 progeny derived from an F1 cross of intense- and faint-blue lines and attempted to identify the genes responsible for flower colour intensity using RNA-sequencing analyses. Comparative analysis of flower colour intensity and transcriptome data revealed differentially expressed genes (DEGs), although known flavonoid biosynthesis-related genes showed similar expression patterns. From quantitative RT-PCR (qRT-PCR) analysis, we identified two and four genes with significantly different expression levels in the intense- and faint-blue flower lines, respectively. We conducted further analyses on one of the DEGs, termed GtMIF1, which encodes a putative mini zinc-finger protein homolog, which was most differently expressed in faint-blue individuals. Functional analysis of GtMIF1 was performed by producing stable tobacco transformants. GtMIF1-overexpressing tobacco plants showed reduced flower colour intensity compared with untransformed control plants. DNA-marker analysis also confirmed that the GtMIF1 allele of the faint-blue flower line correlated well with faint flower colour in F2 progeny. These results suggest that GtMIF1 is one of the key genes involved in determining the flower colour intensity of gentian.
Collapse
Affiliation(s)
| | - Aiko Watanabe
- Iwate Biotechnology Research Center, Kitakami, Japan
| | | | | | - Fumina Goto
- Iwate Biotechnology Research Center, Kitakami, Japan
| | | | - Takashi Hikage
- Hachimantai City Floricultural Research and Development Center, Hachimantai, Japan
| | | |
Collapse
|
3
|
Kashtwari M, Mansoor S, Wani AA, Najar MA, Deshmukh RK, Baloch FS, Abidi I, Zargar SM. Random mutagenesis in vegetatively propagated crops: opportunities, challenges and genome editing prospects. Mol Biol Rep 2021; 49:5729-5749. [PMID: 34427889 DOI: 10.1007/s11033-021-06650-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 08/15/2021] [Indexed: 12/23/2022]
Abstract
In order to meet the growing human food and nutrition demand a perpetual process of crop improvement is idealized. It has seen changing trends and varying concepts throughout human history; from simple selection to complex gene-editing. Among these techniques, random mutagenesis has been shown to be a promising technology to achieve desirable genetic gain with less time and minimal efforts. Over the decade, several hundred varieties have been released through random mutagenesis, but the production is falling behind the demand. Several food crops like banana, potato, cassava, sweet potato, apple, citrus, and others are vegetatively propagated. Since such crops are not propagated through seed, genetic improvement through classical breeding is impractical for them. Besides, in the case of polyploids, accomplishment of allelic homozygosity requires a considerable land area, extensive fieldwork with huge manpower, and hefty funding for an extended period of time. Apart from induction, mapping of induced genes to facilitate the knowledge of biological processes has been performed only in a few selected facultative vegetative crops like banana and cassava which can form a segregating population. During the last few decades, there has been a shift in the techniques used for crop improvement. With the introduction of the robust technologies like meganucleases, zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and clustered regularly interspaced short palindromic repeats (CRISPR) more and more crops are being subjected to gene editing. However, more work needs to be done in case of vegetatively propagated crops.
Collapse
Affiliation(s)
- Mahpara Kashtwari
- Cytogenetics and Molecular Biology Laboratory, Department of Botany, University of Kashmir, Hazratbal, Srinagar, Jammu and Kashmir, 190006, India
| | - Sheikh Mansoor
- Division of Biochemistry, Sher-e-Kashmir University of Agricultural Sciences and Technology, FBSc, Jammu, Jammu and Kashmir, 180009, India
| | - Aijaz A Wani
- Cytogenetics and Molecular Biology Laboratory, Department of Botany, University of Kashmir, Hazratbal, Srinagar, Jammu and Kashmir, 190006, India.
| | - Mushtaq Ahmad Najar
- Cytogenetics and Molecular Biology Laboratory, Department of Botany, University of Kashmir, Hazratbal, Srinagar, Jammu and Kashmir, 190006, India
| | - Rupesh K Deshmukh
- National Agri-Food Biotechnology Institute (NABI), Mohali, Punjab, 140308, India
| | - Faheem Shehzad Baloch
- Faculty of Agricultural Sciences and Technologies, Sivas University of Science and Technology, Sivas, Turkey
| | - Ishfaq Abidi
- Directorate of Research, Sher-e-Kashmir University of Agricultural Sciences and Technology, Shalimar, Jammu and Kashmir, 190025, India
| | - Sajad Majeed Zargar
- Proteomics Laboratory, Division of Plant Biotechnology, Sher-e-Kashmir University of Agricultural Sciences and Technology, Shalimar, Jammu and Kashmir, 190025, India.
| |
Collapse
|
4
|
Hosoguchi T, Uchiyama Y, Komazawa H, Yahata M, Shimokawa T, Tominaga A. Effect of Three Types of Ion Beam Irradiation on Gerbera ( Gerbera hybrida) In Vitro Shoots with Mutagenesis Efficiency. PLANTS 2021; 10:plants10071480. [PMID: 34371682 PMCID: PMC8309275 DOI: 10.3390/plants10071480] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/01/2021] [Accepted: 07/14/2021] [Indexed: 11/28/2022]
Abstract
Gerbera in vitro shoots were irradiated using three types of ion beams with different line energy transfers (LETs) to investigate the effective LET and absorbed doses for mutagenesis. Furthermore, genomic mutation analyses were conducted on the obtained mutants. Survival rate analysis showed a lower lethal dose 50% (LD50) with ion beams with higher LETs. Trait/morphological mutations exhibited changes in the color and shape of petals and male sterility. Irradiation conditions with the highest growth change and trait/morphological mutation rates in each ion were C irradiation at 10 Gy, Ar irradiation at 5 Gy, and Fe irradiation at 5 Gy, with a range of absorbed dose of around LD50 to about 10 Gy lower. The highest trait/morphological mutation rate was 14.1% with Ar irradiation at 5 Gy, which was one of the criteria for ion beam irradiation of gerbera in vitro shoots. Furthermore, the genomic mutation in the flower color, petal shape, and male sterile mutants were confirmed by genotype analysis using Genotyping by Random Amplicon Sequencing-Direct technology. This is the first study to report the efficient production of gerbera mutants that could be analyzed. Our findings may lead to more efficient gerbera mutant production and analysis technology.
Collapse
Affiliation(s)
- Tomoya Hosoguchi
- Department of Agriculture, Graduate School of Integrated Science and Technology, Shizuoka University, Shizuoka 422-8529, Japan; (T.H.); (Y.U.); (M.Y.)
| | - Yuna Uchiyama
- Department of Agriculture, Graduate School of Integrated Science and Technology, Shizuoka University, Shizuoka 422-8529, Japan; (T.H.); (Y.U.); (M.Y.)
| | - Hinata Komazawa
- Faculty of Agriculture, Shizuoka University, Shizuoka 422-8529, Japan;
| | - Masaki Yahata
- Department of Agriculture, Graduate School of Integrated Science and Technology, Shizuoka University, Shizuoka 422-8529, Japan; (T.H.); (Y.U.); (M.Y.)
- Faculty of Agriculture, Shizuoka University, Shizuoka 422-8529, Japan;
| | - Takashi Shimokawa
- Department of Accelerator and Medical Physics, National Institutes of Quantum and Radiological Science and Technology, Chiba 263-8555, Japan;
| | - Akiyoshi Tominaga
- Department of Agriculture, Graduate School of Integrated Science and Technology, Shizuoka University, Shizuoka 422-8529, Japan; (T.H.); (Y.U.); (M.Y.)
- Faculty of Agriculture, Shizuoka University, Shizuoka 422-8529, Japan;
- Correspondence:
| |
Collapse
|
5
|
Takahashi S, Ozawa S, Sonoike K, Sasaki K, Nishihara M. Morphological and cytological observations of corolla green spots reveal the presence of functional chloroplasts in Japanese gentian. PLoS One 2020; 15:e0237173. [PMID: 32845897 PMCID: PMC7449470 DOI: 10.1371/journal.pone.0237173] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 07/21/2020] [Indexed: 11/19/2022] Open
Abstract
Gentian is an important ornamental flower in Japan. The corolla of the majority of cultivated Japanese gentians have green spots, which are rarely encountered in flowers of other angiosperms. Little information is available on the functional traits of the green spots. In this study, we characterized the green spots in the Japanese gentian corolla using a number of microscopic techniques. Opto-digital microscopy revealed that a single visible green spot is composed of approximately 100 epidermal cells. The epidermal cells of a green spot formed a dome-like structure and the cell lumen contained many green structures that were granular and approximately 5 μm in diameter. The green structures emitted red autofluorescence when irradiated with 488 nm excitation light. Transmission electron microscopy revealed that the green structures contained typical thylakoids and grana, thus indicating they are chloroplasts. No grana were observed and the thylakoids had collapsed in the plastids of epidermal cells surrounding green spots. To estimate the rate of photosynthetic electron transfer of the green spots, we measured chlorophyll fluorescence using the MICROSCOPY version of an Imaging-PAM (pulse-amplitude-modulated) fluorometer. Under actinic light of 449 μmol m-2 s-1, substantial electron flow through photosystem II was observed. Observation of green spot formation during corolla development revealed that immature green spots formed at an early bud stage and developed to maturity associated with chloroplast degradation in the surrounding epidermal cells. These results confirmed that the Japanese gentian corolla contains functional chloroplasts in restricted areas of epidermal cells and indicated that a sophisticated program for differential regulation of chloroplast formation and degradation is operative in the epidermis.
Collapse
Affiliation(s)
| | - Suguru Ozawa
- Iwate Agricultural Research Center, Kitakami, Iwate, Japan
| | - Kintake Sonoike
- Faculty of Education and Integrated Arts and Sciences, Waseda University, Shinjuku-ku, Tokyo, Japan
| | - Katsutomo Sasaki
- Institute of Vegetable and Floriculture Science, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan
| | | |
Collapse
|
6
|
Nishihara M, Higuchi A, Watanabe A, Tasaki K. Application of the CRISPR/Cas9 system for modification of flower color in Torenia fournieri. BMC PLANT BIOLOGY 2018; 18:331. [PMID: 30518324 PMCID: PMC6280492 DOI: 10.1186/s12870-018-1539-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 11/20/2018] [Indexed: 05/02/2023]
Abstract
BACKGROUND CRISPR/Cas9 technology is one of the most powerful and useful tools for genome editing in various living organisms. In higher plants, the system has been widely exploited not only for basic research, such as gene functional analysis, but also for applied research such as crop breeding. Although the CRISPR/Cas9 system has been used to induce mutations in genes involved in various plant developmental processes, few studies have been performed to modify the color of ornamental flowers. We therefore attempted to use this system to modify flower color in the model plant torenia (Torenia fournieri L.). RESULTS We attempted to induce mutations in the torenia flavanone 3-hydroxylase (F3H) gene, which encodes a key enzyme involved in flavonoid biosynthesis. Application of the CRISPR/Cas9 system successfully generated pale blue (almost white) flowers at a high frequency (ca. 80% of regenerated lines) in transgenic torenia T0 plants. Sequence analysis of PCR amplicons by Sanger and next-generation sequencing revealed the occurrence of mutations such as base substitutions and insertions/deletions in the F3H target sequence, thus indicating that the obtained phenotype was induced by the targeted mutagenesis of the endogenous F3H gene. CONCLUSIONS These results clearly demonstrate that flower color modification by genome editing with the CRISPR/Cas9 system is easily and efficiently achievable. Our findings further indicate that this system may be useful for future research on flower pigmentation and/or functional analyses of additional genes in torenia.
Collapse
Affiliation(s)
- Masahiro Nishihara
- Iwate Biotechnology Research Center, 22-174-4, Narita, Kitakami, Iwate, 024-0003 Japan
| | - Atsumi Higuchi
- Iwate Biotechnology Research Center, 22-174-4, Narita, Kitakami, Iwate, 024-0003 Japan
| | - Aiko Watanabe
- Iwate Biotechnology Research Center, 22-174-4, Narita, Kitakami, Iwate, 024-0003 Japan
| | - Keisuke Tasaki
- Iwate Biotechnology Research Center, 22-174-4, Narita, Kitakami, Iwate, 024-0003 Japan
- Present Address: Tokyo University of Agriculture, Atsugi, Kanagawa 243-0034 Japan
| |
Collapse
|