Genome Editing Targets for Improving Nutrient Use Efficiency and Nutrient Stress Adaptation

Abstract

In recent years, the development of RNA-guided genome editing (CRISPR-Cas9 technology) has revolutionized plant genome editing. Under nutrient deficiency conditions, different transcription factors and regulatory gene networks work together to maintain nutrient homeostasis. Improvement in the use efficiency of nitrogen (N), phosphorus (P) and potassium (K) is essential to ensure sustainable yield with enhanced quality and tolerance to stresses. This review outlines potential targets suitable for genome editing for understanding and improving nutrient use (NtUE) efficiency and nutrient stress tolerance. The different genome editing strategies for employing crucial negative and positive regulators are also described. Negative regulators of nutrient signalling are the potential targets for genome editing, that may improve nutrient uptake and stress signalling under resource-poor conditions. The promoter engineering by CRISPR/dead (d) Cas9 (dCas9) cytosine and adenine base editing and prime editing is a successful strategy to generate precise changes. CRISPR/dCas9 system also offers the added advantage of exploiting transcriptional activators/repressors for overexpression of genes of interest in a targeted manner. CRISPR activation (CRISPRa) and CRISPR interference (CRISPRi) are variants of CRISPR in which a dCas9 dependent transcription activation or interference is achieved. dCas9-SunTag system can be employed to engineer targeted gene activation and DNA methylation in plants. The development of nutrient use efficient plants through CRISPR-Cas technology will enhance the pace of genetic improvement for nutrient stress tolerance of crops and improve the sustainability of agriculture.

Mineral nutrients in plants under changing environments: A road to future food and nutrition security

“…The enhancement of iron availability may be attributed to the increase in Cys concentration in the endosperm (Majumder et al, 2019). (Ceasar et al, 2022;Sathee et al, 2022). Alam et al (2022) used the CRISPR/Cas9 system to knock out the OsbHLH024 gene in rice that resulted in increase in the levels of Ca 2+ , The Plant Genome Zn 2+ , and Mg 2+ in the shoot and root, as well as the expression of ion transporter genes OsHKT1;3, OsHAK7, and OsSOS1, thereby improving salt tolerance.…”

“…Genome editing cutting‐edge biotechnological techniques offers a new paradigm for undertaking target‐specific precision editing to engineer a plant's genome. The recent advancement of CRISPR/Cas9‐based genome editing technologies in crops has emerged as a new generation breeding tool in the development of climate resilient crops, enhancement of nutrient content with optimized yield in crop plants (Ceasar et al., 2022; Sathee et al., 2022). Alam et al.…”

Plant nitrogen availability and crosstalk with phytohormones signallings and their biotechnology breeding application in crops

“…Emerging CRISPR/Cas tools can precisely modify target genes with CRISPR interference, CRISPR activation (specific gene silencing and activation), CRISPR base‐editing, and CRISPR prime editing without disturbing the genetic makeup to create new non‐transgenic plants, which have occurred at a breathtaking pace in the development of genome‐editing technologies (Ceasar et al ., 2022 ; Jiang et al ., 2021 ; Liu et al ., 2022 ; Metje‐Sprink et al ., 2020 ; Sathee et al ., 2022 ). CRISPR/Cas9 targeting ZmGA3 OX blocks GA biosynthesis, which down‐regulates N transport‐related genes and represses N uptake in maize (Wang et al ., 2020b ).…”

Photosynthetic machinery under salinity stress: Trepidations and adaptive mechanisms

“…These effects are the outcome of the pro-oxidant function of the PTOX gene that leads to the formation of superoxide molecules (Krieger-Liszkay and Feilke 2016) (Table 1). These types of negative regulatory genes are being targeted for genome editing by CRISPR/Cas for imparting salinity tolerance in crop plants (Sathee et al 2022). Thus, the various alterations in membrane proteins contribute to defective photosynthesis in chloroplasts.…”

“…Plants are forced to maintain an optimization between nutrient uptake and restriction of the entry of salinity-associated ions. The genome editing targets for such tradeoffs are reported from various plants (Sathee et al 2022). Salinity stress is a major global environmental challenge that degrades land and impairs production in a vast majority of crops (Soltabayeva et al 2021).…”