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Gene editing technologies have opened up the possibility of manipulating the genome of any organism in a predicted way. CRISPR technology is the most used genome editing tool and, in agriculture, it has allowed the expansion of possibilities in plant biotechnology, such as gene knockout or knock-in, transcriptional regulation, epigenetic modification, base editing, RNA editing, prime editing, and nucleic acid probing or detection. This technology mostly depends on in vitro tissue culture and genetic transformation/transfection protocols, which sometimes become the major challenges for its application in different crops. Agrobacterium-mediated transformation, biolistics, plasmid or RNP (ribonucleoprotein) transfection of protoplasts are some of the commonly used CRISPR delivery methods, but they depend on the genotype and target gene for efficient editing. The choice of the CRISPR system (Cas9, Cas12), CRISPR mechanism (plasmid or RNP) and transfection technique (Agrobacterium spp., PEG solution, lipofection) directly impacts the transformation efficiency and/or editing rate. Besides, CRISPR/Cas technology has made countries rethink regulatory frameworks concerning genetically modified organisms and flexibilize regulatory obstacles for edited plants. Here we present an overview of the state-of-the-art of CRISPR technology applied to three important crops worldwide (citrus, coffee and sugarcane), considering the biological, methodological, and regulatory aspects of its application. In addition, we provide perspectives on recently developed CRISPR tools and promising applications for each of these crops, thus highlighting the usefulness of gene editing to develop novel cultivars., Competing Interests: LP and MM was employed by Brazilian Agricultural Research Corporation. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision. The authors declare that this study received funding from Embrapa (Brazilian Agricultural Research Corporation, Brasília-DF, Brazil). The funder had the following involvement with the study: preparation of the manuscript., (Copyright © 2024 Prado, Rocha, Santos, Contiliani, Nobile, Martinati-Schenk, Padilha, Maluf, Lubini, Pereira, Monteiro-Vitorello, Creste, Boscariol-Camargo, Takita, Cristofani-Yaly and Souza.)

Antimicrobial peptides are small molecules, up to 10 kDa, present in all kingdoms of life, including in plants. Several studies report that these molecules have a broad spectrum of activity, including antibacterial, antifungal, antiviral, and insecticidal activity. Thus, they can be employed in agriculture as alternative tools for phytopathogen and pest control. However, the application of peptides in agriculture can present challenges, such as loss of activity due to degradation of these molecules, off-target effects, and others. In this context, nanotechnology can offer versatile structures, including metallic nanoparticles, liposomes, polymeric nanoparticles, nanofibers, and others, which might act both in protection and in release of AMPs. Several polymers and biomaterials can be employed for the development of nanostructures, such as inorganic metals, natural or synthetic lipids, synthetic and hybrid polymers, and others. This review addresses the versatility of NanoAMPs (Nanoparticles in association with antimicrobial peptides), and their potential applications in agribusiness, as an alternative for the control of phytopathogens in crops., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Maximiano, Rios, Campos, Prado, Dias and Franco.)

The natural increase of the world's population implies boosting agricultural demand. In the current non-optimistic global scenario, where adverse climate changes come associated with substantial population growth, the main challenge in agribusiness is food security. Recently, the CRISPR/Cas system has emerged as a friendly gene editing biotechnological tool, enabling a precise manipulation of genomes and enhancement of desirable traits in several organisms. This review highlights the CRISPR/Cas system as a paramount tool for the improvement of agribusiness products and brings up-to-date findings showing its potential applications in improving agricultural-related traits in major plant crops and farm animals, all representing economic-relevant commodities responsible for feeding the world. Several applied pieces of research have successfully demonstrated the CRISPR/Cas ability in boosting interesting traits in agribusiness products, including animal productivity and welfare, crop yield growth, and seed quality, reflecting positive impacts in both socioeconomics and human health aspects. Hence, the CRISPR/Cas system has revolutionized bioscience and biotechnology, and its concrete application in agribusiness goods is on the horizon.

Mosses have long been recognized as powerful experimental tools for the elucidation of complex processes in plant biology. Recent increases in the availability of sequenced genomes and mutant collections, the establishment of novel technologies for targeted mutagenesis, and the development of viable protocols for large-scale production in bioreactors are now transforming mosses into one of the most versatile tools for biotechnological applications. In the present review, we highlight the astonishing biotechnological potential of mosses and how these plants are being exploited for industrial, pharmaceutical, and environmental applications. We focus on the biological features that support their use as model organisms for basic and applied research, and how these are being leveraged to explore the biotechnological potential in an increasing number of species. Finally, we also provide an overview of the available moss cultivation protocols from an industrial perspective, offering insights into batch operations that are not yet well established or do not even exist in the literature. Our goal is to bolster the use of mosses as factories for the biosynthesis of molecules of interest and to show how these species can be harnessed for the generation of novel and commercially useful bioproducts., (Copyright © 2020 Elsevier Inc. All rights reserved.)

[This corrects the article DOI: 10.3389/fpls.2019.00414.]., (Copyright © 2020 Santos, Nogueira, Domont, Fontes, Prado, Habibi, Santos, Oliveira-Neto, Grossi-de-Sá, Jorrín-Novo, Franco and Mehta.)

In the last years, the production of ethanol fuel has started to change with the introduction of second-generation ethanol (2 G Ethanol) in the energy sector. However, in Brazil, the process of obtaining 2 G ethanol did not reach a basic standard to achieve relevant and economically viable results. Several studies have currently been addressed to solve these issues. A critical stage in the bioethanol production is the deployment of efficient and stable enzymes to catalyze the saccharification step into the process of biomass conversion. The present study comprises a screening for genes coding for plant biomass degradation enzymes, followed by cloning a selected gene, addressing its heterologous expression, and characterizing enzymatic activity towards cellulose derived substrates, with a view to second-generation ethanol production. A cDNA database of the Cotton Boll Weevil, Anthonomus grandis (Coleoptera: Curculionidae), an insect that feeds on cotton plant biomass, was used as a source of plant biomass degradation enzyme genes. A larva and adult midgut-specific β-1,4-Endoglucanase-coding gene (AgraGH45-1) was cloned and expressed in the yeast Pichia pastoris. Its amino acid sequence, including the two catalytic domains, shares high identity with other Coleoptera Glycosyl Hydrolases from family 45 (GH45). AgraGH45-1 activity was detected in a Carboxymethylcellulose (CMC) and Hydroxyethylcellulose (HEC) degradation assay and the optimal conditions for enzymatic activity was pH 5.0 at 50 °C. When compared to commercial cellulase from Aspergillus niger, Agra GH45-1 was 1.3-fold more efficient to degrade HEC substrate. Together, these results show that AgraGH45-1 is a valid candidate to be engineered and be tested for 2 G ethanol production.

Black rot is a severe disease caused by the bacterium Xanthomonas campestris pv. campestris (Xcc), which can lead to substantial losses in cruciferous vegetable production worldwide. Although the use of resistant cultivars is the main strategy to control this disease, there are limited sources of resistance. In this study, we used the LC-MS/MS technique to analyze young cabbage leaves and chloroplast-enriched samples at 24 h after infection by Xcc, using both susceptible (Veloce) and resistant (Astrus) cultivars. A comparison between susceptible Xcc-inoculated plants and the control condition, as well as between resistant Xcc-inoculated plants with the control was performed and more than 300 differentially abundant proteins were identified in each comparison. The chloroplast enriched samples contributed with the identification of 600 additional protein species in the resistant interaction and 900 in the susceptible one, which were not detected in total leaf sample. We further determined the expression levels for 30 genes encoding the identified differential proteins by qRT-PCR. CHI-B4 like gene, encoding an endochitinase showing a high increased abundance in resistant Xcc-inoculated leaves, was selected for functional validation by overexpression in Arabidopsis thaliana. Compared to the wild type (Col-0), transgenic plants were highly resistant to Xcc indicating that CHI-B4 like gene could be an interesting candidate to be used in genetic breeding programs aiming at black rot resistance.

Background: Insect resistance in crops represents a main challenge for agriculture. Transgenic approaches based on proteins displaying insect resistance properties are widely used as efficient breeding strategies. To extend the spectrum of targeted pathogens and overtake the development of resistance, molecular evolution strategies have been used on genes encoding these proteins to generate thousands of variants with new or improved functions. The cotton boll weevil (Anthonomus grandis) is one of the major pests of cotton in the Americas. An α-amylase inhibitor (α-AIC3) variant previously developed via molecular evolution strategy showed inhibitory activity against A. grandis α-amylase (AGA)., Results: We produced in a few days considerable amounts of α-AIC3 using an optimised transient heterologous expression system in Nicotiana benthamiana. This high α-AIC3 accumulation allowed its structural and functional characterizations. We demonstrated via MALDI-TOF MS/MS technique that the protein was processed as expected. It could inhibit up to 100% of AGA biological activity whereas it did not act on α-amylase of two non-pathogenic insects. These data confirmed that N. benthamiana is a suitable and simple system for high-level production of biologically active α-AIC3. Based on other benefits such as economic, health and environmental that need to be considerate, our data suggested that α-AIC3 could be a very promising candidate for the production of transgenic crops resistant to cotton boll weevil without lethal effect on at least two non-pathogenic insects., Conclusions: We propose this expression system can be complementary to molecular evolution strategies to identify the most promising variants before starting long-lasting stable transgenic programs.

The exploration of emerging host organisms for the economic and efficient production of protein microbicides against HIV is urgently needed in resource-poor areas worldwide. In this study, the production of the novel HIV entry inhibitor candidate, griffithsin (GRFT), was investigated using Nicotiana benthamiana as the expression platform based on a non-viral vector. To increase the yield of recombinant GRFT, the RNA silencing defense mechanism of N. benthamiana was abolished by using three gene silencing suppressors. A transient expression system was used by transferring the GRFT gene, which encodes 122 amino acids, under the control of the enhanced CaMV 35S promoter. The presence of correctly assembled GRFT in transgenic leaves was confirmed using immunoglobulin-specific sandwich ELISA. The data demonstrated that the use of three gene silencing suppressors allowed the highest accumulation of GRFT, with a yield of 400 μg g -1 fresh weight, and this amount was reduced to 287 μg g -1 after purification, representing a recovery of 71.75%. The analysis also showed that the ability of GRFT expressed in N. benthamiana to bind to glycoprotein 120 is close to that of the GRFT protein purified from E. coli. Whole-cell assays using purified GRFT showed that our purified GRFT was potently active against HIV. This study provides the first high-level production of the HIV-1 entry inhibitor griffithsin with a non-viral expression system and illustrates the robustness of the co-agroinfiltration expression system improved through the use of three gene silencing suppressors., (© 2018 Elsevier Ltd. All rights reserved.)

The increasing volume of genomic data on the Phaseolus vulgaris species have contributed to its importance as a model genetic species and positively affected the investigation of other legumes of scientific and economic value. To expand and gain a more in-depth knowledge of the common bean genome, the ends of a number of bacterial artificial chromosome (BAC) were sequenced, annotated and the presence of repetitive sequences was determined. In total, 52,270 BESs (BAC-end sequences), equivalent to 32 Mbp (~6 %) of the genome, were processed. In total, 3,789 BES-SSRs were identified, with a distribution of one SSR (simple sequence repeat) per 8.36 kbp and 2,000 were suitable for the development of SSRs, of which 194 were evaluated in low-resolution screening. From 40 BES-SSRs based on long motifs SSRs (≥ trinucleotides) analyzed in high-resolution genotyping, 34 showed an equally good amplification for the Andean and for the Mesoamerican genepools, exhibiting an average gene diversity (H E) of 0.490 and 5.59 alleles/locus, of which six classified as Class I showed a H E ≥ 0.7. The PCoA and structure analysis allowed to discriminate the gene pools (K = 2, FST = 0.733). From the 52,270 BESs, 2 % corresponded to transcription factors and 3 % to transposable elements. Putative functions for 24,321 BESs were identified and for 19,363 were assigned functional categories (gene ontology). This study identified highly polymorphic BES-SSRs containing tri- to hexanucleotides motifs and bringing together relevant genetic characteristics useful for breeding programs. Additionally, the BESs were incorporated into the international genome-sequencing project for the common bean.