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Gaillochet C, Peña Fernández A, Goossens V, D'Halluin K, Drozdzecki A, Shafie M, Van Duyse J, Van Isterdael G, Gonzalez C, Vermeersch M, De Saeger J, Develtere W, Audenaert D, De Vleesschauwer D, Meulewaeter F, Jacobs TB. Systematic optimization of Cas12a base editors in wheat and maize using the ITER platform. Genome Biol 2023; 24:6. [PMID: 36639800 PMCID: PMC9838060 DOI: 10.1186/s13059-022-02836-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 12/06/2022] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Testing an ever-increasing number of CRISPR components is challenging when developing new genome engineering tools. Plant biotechnology has few high-throughput options to perform iterative design-build-test-learn cycles of gene-editing reagents. To bridge this gap, we develop ITER (Iterative Testing of Editing Reagents) based on 96-well arrayed protoplast transfections and high-content imaging. RESULTS We validate ITER in wheat and maize protoplasts using Cas9 cytosine and adenine base editors (ABEs), allowing one optimization cycle - from design to results - within 3 weeks. Given that previous LbCas12a-ABEs have low or no activity in plants, we use ITER to develop an optimized LbCas12a-ABE. We show that sequential improvement of five components - NLS, crRNA, LbCas12a, adenine deaminase, and linker - leads to a remarkable increase in activity from almost undetectable levels to 40% on an extrachromosomal GFP reporter. We confirm the activity of LbCas12a-ABE at endogenous targets in protoplasts and obtain base-edited plants in up to 55% of stable wheat transformants and the edits are transmitted to T1 progeny. We leverage these improvements to develop a highly mutagenic LbCas12a nuclease and a LbCas12a-CBE demonstrating that the optimizations can be broadly applied to the Cas12a toolbox. CONCLUSION Our data show that ITER is a sensitive, versatile, and high-throughput platform that can be harnessed to accelerate the development of genome editing technologies in plants. We use ITER to create an efficient Cas12a-ABE by iteratively testing a large panel of vector components. ITER will likely be useful to create and optimize genome editing reagents in a wide range of plant species.
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Affiliation(s)
- Christophe Gaillochet
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
| | - Alexandra Peña Fernández
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
| | - Vera Goossens
- Screening Core, VIB, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- Centre for Bioassay Development and Screening (C-BIOS), Ghent University, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
| | - Katelijn D'Halluin
- BASF Belgium Coordination Center CommV, Innovation Center Gent, Technologiepark-Zwijnaarde 101, 9052, Ghent, Belgium
| | - Andrzej Drozdzecki
- Screening Core, VIB, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- Centre for Bioassay Development and Screening (C-BIOS), Ghent University, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
| | - Myriam Shafie
- BASF Belgium Coordination Center CommV, Innovation Center Gent, Technologiepark-Zwijnaarde 101, 9052, Ghent, Belgium
| | - Julie Van Duyse
- VIB Flow Core, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
| | | | - Camila Gonzalez
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
| | - Mattias Vermeersch
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
| | - Jonas De Saeger
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
| | - Ward Develtere
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
| | - Dominique Audenaert
- Screening Core, VIB, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- Centre for Bioassay Development and Screening (C-BIOS), Ghent University, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
| | - David De Vleesschauwer
- BASF Belgium Coordination Center CommV, Innovation Center Gent, Technologiepark-Zwijnaarde 101, 9052, Ghent, Belgium
| | - Frank Meulewaeter
- BASF Belgium Coordination Center CommV, Innovation Center Gent, Technologiepark-Zwijnaarde 101, 9052, Ghent, Belgium
| | - Thomas B Jacobs
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium.
- VIB Center for Plant Systems Biology, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium.
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Ma Y, Li D, Xu Z, Gu R, Wang P, Fu J, Wang J, Du W, Zhang H. Dissection of the Genetic Basis of Yield Traits in Line per se and Testcross Populations and Identification of Candidate Genes for Hybrid Performance in Maize. Int J Mol Sci 2022; 23:5074. [PMID: 35563470 PMCID: PMC9102962 DOI: 10.3390/ijms23095074] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/22/2022] [Accepted: 04/25/2022] [Indexed: 12/31/2022] Open
Abstract
Dissecting the genetic basis of yield traits in hybrid populations and identifying the candidate genes are important for molecular crop breeding. In this study, a BC1F3:4 population, the line per se (LPS) population, was constructed by using elite inbred lines Zheng58 and PH4CV as the parental lines. The population was genotyped with 55,000 SNPs and testcrossed to Chang7-2 and PH6WC (two testers) to construct two testcross (TC) populations. The three populations were evaluated for hundred kernel weight (HKW) and yield per plant (YPP) in multiple environments. Marker-trait association analysis (MTA) identified 24 to 151 significant SNPs in the three populations. Comparison of the significant SNPs identified common and specific quantitative trait locus/loci (QTL) in the LPS and TC populations. Genetic feature analysis of these significant SNPs proved that these SNPs were associated with the tested traits and could be used to predict trait performance of both LPS and TC populations. RNA-seq analysis was performed using maize hybrid varieties and their parental lines, and differentially expressed genes (DEGs) between hybrid varieties and parental lines were identified. Comparison of the chromosome positions of DEGs with those of significant SNPs detected in the TC population identified potential candidate genes that might be related to hybrid performance. Combining RNA-seq analysis and MTA results identified candidate genes for hybrid performance, providing information that could be useful for maize hybrid breeding.
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Affiliation(s)
- Yuting Ma
- Agronomy College, Shenyang Agricultural University, Shenyang 110866, China;
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (D.L.); (P.W.); (J.F.)
| | - Dongdong Li
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (D.L.); (P.W.); (J.F.)
| | - Zhenxiang Xu
- Center for Seed Science and Technology, College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China; (Z.X.); (R.G.); (J.W.)
| | - Riliang Gu
- Center for Seed Science and Technology, College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China; (Z.X.); (R.G.); (J.W.)
| | - Pingxi Wang
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (D.L.); (P.W.); (J.F.)
| | - Junjie Fu
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (D.L.); (P.W.); (J.F.)
| | - Jianhua Wang
- Center for Seed Science and Technology, College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China; (Z.X.); (R.G.); (J.W.)
| | - Wanli Du
- Agronomy College, Shenyang Agricultural University, Shenyang 110866, China;
| | - Hongwei Zhang
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (D.L.); (P.W.); (J.F.)
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Jackson D, Tian F, Zhang Z. Maize genetics, genomics, and sustainable improvement. MOLECULAR BREEDING : NEW STRATEGIES IN PLANT IMPROVEMENT 2022; 42:2. [PMID: 37309482 PMCID: PMC10248613 DOI: 10.1007/s11032-021-01266-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/08/2021] [Indexed: 06/14/2023]
Affiliation(s)
- David Jackson
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724 USA
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070 China
| | - Feng Tian
- State Key Laboratory of Plant Physiology and Biochemistry, National Maize Improvement Center of China, and Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing, 100193 China
| | - Zuxin Zhang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070 China
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