Attaining the promise of plant gene editing at scale

Abstract

Crop improvement relies heavily on genetic variation that arises spontaneously through mutation. Modern breeding methods are very adept at combining this genetic variation in ways that achieve remarkable improvements in plant performance. Novel traits have also been created through mutation breeding and transgenesis. The advent of gene editing, however, marks a turning point: With gene editing, synthetic variation will increasingly supplement and, in some cases, supplant the genetic variation that occurs naturally. We are still in the very early stages of realizing the opportunity provided by plant gene editing. At present, typically only one or a few genes are targeted for mutation at a time, and most mutations result in loss of gene function. New technological developments, however, promise to make it possible to perform gene editing at scale. RNA virus vectors, for example, can deliver gene-editing reagents to the germ line through infection and create hundreds to thousands of diverse mutations in the progeny of infected plants. With developmental regulators, edited somatic cells can be induced to form meristems that yield seed-producing shoots, thereby increasing throughput and shrinking timescales for creating edited plants. As these approaches are refined and others developed, they will allow for accelerated breeding, the domestication of orphan crops and the reengineering of metabolism in a more directed manner than has ever previously been possible.

Principles of Nanoparticle Design for Genome Editing in Plants

“… The current modes of cargo delivery that can be employed for CRISPR Cas reagent delivery in planta : nanoparticle-mediated ( Lew et al, 2020c ), viral infection ( Ma et al, 2020 ), Agrobacterium ( Zhang et al, 2019c ), biolistic gene-gun ( Miller et al, 2021 ), magnetofection ( Zhao et al, 2017 ), tissue culture ( Nasti and Voytas, 2021 ) and cationic delivery ( Duan et al, 2021 ) (Created with BioRender.com ). …”

Non-GM Genome Editing Approaches in Crops

“…Plant breeding aims to produce improved crop varieties with enhanced agronomic traits and better nutrition qualities for a growing human population. However, traditional breeding methods are often slow, and the production of new traits is restricted by the species’ existing genetic variation pool ( Voytas and Gao, 2014 ; Baltes et al, 2017 ; Mao et al, 2019 ; Wang et al, 2019 ; Nasti and Voytas, 2021 ).…”

Analyzing Plant Gene Targeting Outcomes and Conversion Tracts with Nanopore Sequencing

“…Primers placed within the homology arms of a donor molecule will amplify both the target locus and donor molecules creating false positives, while primers placed outside the regions of homology will typically yield amplicons too large for analyses. While it is possible to remove the donor via long-term propagation or regeneration of edited cells, this process remains resource intensive and low throughput in plants [ 5 ].…”