Targeted plant improvement through genome editing: from laboratory to field

This review illustrates how far we have come since the emergence of GE technologies and how they could be applied to obtain superior and sustainable crop production. The main challenges of today's agriculture are maintaining and raising productivity, reducing its negative impact on the environment, and adapting to climate change. Efficient plant breeding can generate elite varieties that will rapidly replace obsolete ones and address ongoing challenges in an efficient and sustainable manner. Site-specific genome editing in plants is a rapidly evolving field with tangible results. The technology is equipped with a powerful toolbox of molecular scissors to cut DNA at a pre-determined site with different efficiencies for designing an approach that best suits the objectives of each plant breeding strategy. Genome editing (GE) not only revolutionizes plant biology, but provides the means to solve challenges related to plant architecture, food security, nutrient content, adaptation to the environment, resistance to diseases and production of plant-based materials. This review illustrates how far we have come since the emergence of these technologies and how these technologies could be applied to obtain superior, safe and sustainable crop production. Synergies of genome editing with other technological platforms that are gaining significance in plants lead to an exciting new, post-genomic era for plant research and production. In previous months, we have seen what global changes might arise from one new virus, reminding us of what drastic effects such events could have on food production. This demonstrates how important science, technology, and tools are to meet the current time and the future. Plant GE can make a real difference to future sustainable food production to the benefit of both mankind and our environment.European Cooperation in Science and Technology (COST) CA18111info:eu-repo/semantics/publishedVersio

Artificial microRNA derived from the precursors of Ananas comosus, Arabidopsis thaliana, and Oryza sativa effectively silences endogenous genes in MD2 pineapple

Artificial microRNA (amiRNA) is considered the next generation of gene silencing vectors because it can be custom designed to silence any gene of interest in an organism. In the amiRNA mechanism, the precursor microRNA (pre-miRNA) plays an important role in transporting and ensuring that the amiRNA is processed through the endogenous miRNA biogenesis pathway, allowing for the amiRNA to be expressed and function as a gene silencing tool. However, the efficiency of expressing amiRNA between miRNA precursors and plant species varies, as there are no universal precursors that are suitable for use in all species. We therefore attempted to identify precursors that are compatible and efficient for use in the MD2 pineapple with the eventual purpose of studying gene function in the crop. The results showed that three endogenous precursors (aco-MIR156, aco- MIR399 and aco-MIR2673 of Ananas comosus) and two exogenous precursors (ath-MIR319 of Arabidopsis thaliana and osa-MIR528 of Oryza sativa) were compatible in the MD2 pineapple, all of which expressed amiRNA. However, the efficiency of these precursors differed, with the exogenous precursor ath-MIR319 found to be more efficient, that is, produced a higher level of amiRNA than the endogenous precursor itself. The endogenous precursors were then structurally modified to increase their efficiency. This resulted in precursor aco-MIR156 (with a modified stem structure) expressing the highest level of amiRNA. In conclusion, we identified suitable precursors for the amiRNA backbone in pineapple and showed that aco-MIR156 from pineapple was as equally efficient as established precursors, ath-MIR319 and osa-miR528 derived from Arabidopsis thaliana and Oryza sativa, respectively. This result opens the door to designing a set of precursors which are reusable as a backbone for amiRNA silencing in other non-model species. We recommend this newly developed pineapple amiRNA as a tool in gene silencing as it mimics the endogenous miRNA with high efficiency

Genetic dissection of natural variation in oilseed traits of camelina by whole‐genome resequencing and QTL mapping

Camelina [Camelina sativa (L.) Crantz] is an oilseed crop in the Brassicaceae family that is currently being developed as a source of bioenergy and healthy fatty acids. To facilitate modern breeding efforts through marker-assisted selection and biotechnology, we evaluated genetic variation among a worldwide collection of 222 camelina accessions. We performed whole-genome resequencing to obtain single nucleotide polymorphism (SNP) markers and to analyze genomic diversity. We also conducted phenotypic field evaluations in two consecutive seasons for variations in key agronomic traits related to oilseed production such as seed size, oil content (OC), fatty acid composition, and flowering time. We determined the population structure of the camelina accessions using 161,301 SNPs. Further, we identified quantitative trait loci (QTL) and candidate genes controlling the above field-evaluated traits by genome-wide association studies (GWAS) complemented with linkage mapping using a recombinant inbred line (RIL) population. Characterization of the natural variation at the genome and phenotypic levels provides valuable resources to camelina genetic studies and crop improvement. The QTL and candidate genes should assist in breeding of advanced camelina varieties that can be integrated into the cropping systems for the production of high yield of oils of desired fatty acid composition. © 2021 The Authors. The Plant Genome published by Wiley Periodicals LLC on behalf of Crop Science Society of AmericaOpen access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]