Review Article
Open Access
Fidelity and Delivery: Coupled Barriers in Plant CRISPR-Cas Genome Editing
1
State Key Laboratory of Tree Genetics and Breeding, College of Life Sciences, Nanjing Forestry University, Nanjing 210037, China
* Corresponding Author:
Ali Movahedi,
[email protected]
Volume 1, Issue 2
2026
Received: 29 September 2025
Revised: 23 July 2026
Accepted: 25 July 2026
Published: 11 August 2026
Article Information
Abstract
CRISPR-Cas platforms have transformed plant functional genomics, yet nucleases such as Cas9 and Cas12a remain constrained by two seemingly distinct limitations: imperfect target discrimination and inefficient intracellular delivery. Here, this review proposes that these constraints are functionally coupled through the intracellular abundance, nuclear access, and chromatin residence time of active Cas-gRNA complexes. Off-target activity arises from guide-target mismatch tolerance during R-loop formation, whereas rigid plant cell walls constrain the delivery of RNP and DNA cargo. These processes can become coupled when delivery limitations alter the concentration or duration of active Cas-gRNA exposure. When inefficient delivery is addressed through sustained or elevated nuclease expression, it can increase cumulative active Cas-gRNA exposure and may consequently increase off-target risk. Evidence from maize, rice, wheat, and carrot systems is synthesized and convergent biochemical solutions, including transgene-free RNP delivery, are outlined spanning herbaceous and woody species.
Graphical Abstract
Keywords
R-loop formation kinetics
off-target mutagenesis
ribonucleoprotein delivery
nuclear localization signal
prime editing
Data Availability Statement
Not applicable.
Funding
This work was supported without any funding.
Conflicts of Interest
Ali Movahedi served as an Editor-in-Chief of the Plant Innovation Journal at the time of manuscript submission. To ensure the integrity of the peer-review process, Ali Movahedi was not involved in the editorial handling, peer review, or decision-making process for this manuscript, which was handled independently by another editor.
AI Use Statement
The author declares that no generative AI was used in the preparation of this manuscript.
Ethical Approval and Consent to Participate
Not applicable.
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APA Style
Movahedi, A. (2026). Fidelity and Delivery: Coupled Barriers in Plant CRISPR-Cas Genome Editing. Plant Innovation Journal, 1(2), 118-125. https://doi.org/10.62762/PIJ.2026.809255
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TY - JOUR AU - Movahedi, Ali PY - 2026 DA - 2026/08/11 TI - Fidelity and Delivery: Coupled Barriers in Plant CRISPR-Cas Genome Editing JO - Plant Innovation Journal T2 - Plant Innovation Journal JF - Plant Innovation Journal VL - 1 IS - 2 SP - 118 EP - 125 DO - 10.62762/PIJ.2026.809255 UR - https://www.icck.org/article/abs/PIJ.2026.809255 KW - R-loop formation kinetics KW - off-target mutagenesis KW - ribonucleoprotein delivery KW - nuclear localization signal KW - prime editing AB - CRISPR-Cas platforms have transformed plant functional genomics, yet nucleases such as Cas9 and Cas12a remain constrained by two seemingly distinct limitations: imperfect target discrimination and inefficient intracellular delivery. Here, this review proposes that these constraints are functionally coupled through the intracellular abundance, nuclear access, and chromatin residence time of active Cas-gRNA complexes. Off-target activity arises from guide-target mismatch tolerance during R-loop formation, whereas rigid plant cell walls constrain the delivery of RNP and DNA cargo. These processes can become coupled when delivery limitations alter the concentration or duration of active Cas-gRNA exposure. When inefficient delivery is addressed through sustained or elevated nuclease expression, it can increase cumulative active Cas-gRNA exposure and may consequently increase off-target risk. Evidence from maize, rice, wheat, and carrot systems is synthesized and convergent biochemical solutions, including transgene-free RNP delivery, are outlined spanning herbaceous and woody species. SN - 3142-7596 PB - Institute of Central Computation and Knowledge LA - English ER -
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@article{Movahedi2026Fidelity,
author = {Ali Movahedi},
title = {Fidelity and Delivery: Coupled Barriers in Plant CRISPR-Cas Genome Editing},
journal = {Plant Innovation Journal},
year = {2026},
volume = {1},
number = {2},
pages = {118-125},
doi = {10.62762/PIJ.2026.809255},
url = {https://www.icck.org/article/abs/PIJ.2026.809255},
abstract = {CRISPR-Cas platforms have transformed plant functional genomics, yet nucleases such as Cas9 and Cas12a remain constrained by two seemingly distinct limitations: imperfect target discrimination and inefficient intracellular delivery. Here, this review proposes that these constraints are functionally coupled through the intracellular abundance, nuclear access, and chromatin residence time of active Cas-gRNA complexes. Off-target activity arises from guide-target mismatch tolerance during R-loop formation, whereas rigid plant cell walls constrain the delivery of RNP and DNA cargo. These processes can become coupled when delivery limitations alter the concentration or duration of active Cas-gRNA exposure. When inefficient delivery is addressed through sustained or elevated nuclease expression, it can increase cumulative active Cas-gRNA exposure and may consequently increase off-target risk. Evidence from maize, rice, wheat, and carrot systems is synthesized and convergent biochemical solutions, including transgene-free RNP delivery, are outlined spanning herbaceous and woody species.},
keywords = {R-loop formation kinetics, off-target mutagenesis, ribonucleoprotein delivery, nuclear localization signal, prime editing},
issn = {3142-7596},
publisher = {Institute of Central Computation and Knowledge}
}
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