Increasing the content of oleic acid in peanut seeds is one of the major goals in peanut breeding due to consumer and industry benefits, such as anti-oxidation and long shelf-life. Homeologous ahFAD2A and ahFAD2B genes encode fatty acid desaturases, which are the key enzymes for converting oleic acid to linoleic acid that oxidizes readily. To date, all high oleic acid peanut varieties result from natural mutations occurred in both genes. A method to induce mutations in the genes of other elite cultivars could speed introgression of this valuable trait. The gene-editing approach utilizing CRISPR/Cas9 technology was employed to induce de novo mutations in the ahFAD2 genes using peanut protoplasts and hairy root cultures as models. The hot spot of natural mutation in these genes was selected as the target region. Appropriate sgRNAs were designed and cloned into a CRISPR/Cas9 expression plasmid. As a result of CRISPR/Cas9 activity, three mutations were identified - G448A in ahFAD2A, and 441_442insA and G451T in ahFAD2B. The G448A and 441_442insA mutations are the same as those seen in existing high oleate varieties and the G451T is new mutation. Because natural mutations appear more often in the ahFAD2A gene than in the ahFAD2B gene in subspecies A. hypogaea var. hypogaea, the mutations induced in ahFAD2B by gene editing may be useful in developing high oleate lines with many genetic backgrounds after validation of oleic acid content in the transformed lines. The appearance of the G448A mutation in ahFAD2A is a further benefit for high oleic acid oil content. Overall, these results showed that mutations were, for the first time, induced by CRISPR-based gene editing approach in peanut. This research demonstrated the potential application of gene editing for mutagenesis in peanut and suggested that CRISPR/Cas9 technology may be useful in the peanut breeding programs.

/pdf/mutagenesis-of-fad2-genes-in-peanut-with-crispr-cas9-based-1k5x6x4im3.pdf

Mutagenesis of FAD2 genes in peanut with CRISPR/Cas9 based gene editing

Background The nutritional quality, flavor, and shelf-life of both peanut products and its seeds are dependent on relative quantity of various fatty acids (FAs) like saturated, mono unsaturated fatty acid (MUFA) and poly unsaturated fatty acid (PUFA) present in its oil. High oleic (HO) peanut oils are extremely valued due to its superior nutritional composition for human health and augmented thermo-oxidative stability for industrial purposes. Scope and approach From the research perspective, noteworthy progress has been made during last three decades for the development of peanut lines having HO trait in its oil. In this review, the research achievements, perspectives, and prospects of peanut genetic improvement for HO trait is thoroughly discussed. Key findings and conclusions The research has helped not only understanding the genetics of HO traits and its genotype (G) by environment (E) interaction but also produced an enormous number of HO line throughout the world. Although, as of now, most of the high O/L cultivars developed are the outcome of traditional breeding efforts. But, with the advent of novel molecular techniques like CAPS and AS-PCR assay for HO peanut breeding program, it is extremely easy to achieve the traits through marker assisted selection (MAS) rather than through either conventional or genetic engineering approaches. The availability of peanut genome sequence and identification of different ahFAD2 gene families is also expediting the research for the breeding of HO peanut genotypes.

High oleic peanut breeding: Achievements, perspectives, and prospects

In peanut (Arachis hypogaea L.), the customization of fatty acid profile is an evolving area to fulfil the nutritional needs in the modern market. A total of 174 peanut genotypes, including 167 Indian cultivars, 6 advanced breeding lines and ‘SunOleic’‒ a double mutant line, were investigated using AS-PCRs, CAPS and gene sequencing for the ahFAD2 allele polymorphism, along with its fatty acid compositions. Of these, 80 genotypes were found having substitution (448G>A) mutation only in ahFAD2A gene, while none recorded 1-bp insertion (441_442insA) mutation in ahFAD2B gene. Moreover, 22 wild peanut accessions found lacking both the mutations. Among botanical types, the ahFAD2A mutation was more frequent in ssp. hypogaea (89%) than in ssp. fastigiata (17%). This single allele mutation, found affecting not only oleic to linoleic acid fluxes, but also the composition of other fatty acids in the genotypes studied. Repeated use of a few selected genotypes in the Indian varietal development programs were also eminently reflected in its ahFAD2 allele polymorphism. Absence of known mutations in the wild-relatives indicated the possible origin of these mutations, after the allotetraploidization of cultivated peanut. The SNP analysis of both ahFAD2A and ahFAD2B genes, revealed haplotype diversity of 1.05% and 0.95%, while Ka/Ks ratio of 0.36 and 0.39 respectively, indicating strong purifying selection pressure on these genes. Cluster analysis, using ahFAD2 gene SNPs, showed presence of both mutant and non-mutant genotypes in the same cluster, which might be due the presence of ahFAD2 gene families. This investigation provided insights into the large number of Indian peanut genotypes, covering various aspects related to O/L flux regulation and ahFAD2 gene polymorphism.

/pdf/insights-into-the-indian-peanut-genotypes-for-ahfad2-gene-2frsdfgc9f.pdf

Insights into the Indian Peanut Genotypes for ahFAD2 Gene Polymorphism Regulating Its Oleic and Linoleic Acid Fluxes.

Identification of potential QTLs and genes associated with seed composition traits in peanut (Arachis hypogaea L.) using GWAS and RNA-Seq analysis.

Fatty acid composition of oil crops: genetics and genetic engineering

Natural genetic variation exists in animals and plants. Mining and utilizing this variation may provide benefits for new breed/cultivar development. From screening over 4000 cultivated peanut germplasm accessions, we identified two natural mutant lines (PI 342664 and PI 342666) with 80 % oleic acid by gas chromatography analysis. It is known that FAD2A and FAD2B are the two major genes involved in the conversion of oleic to linoleic acid in peanuts by fatty acid desaturase. Functional mutations in one or both genes can alter the oleate level. By sequencing the coding region of these two genes, we identified a substitution of G448A in FAD2A and a substitution of C301G in FAD2B for both mutant lines. The substitution in FAD2A is the same as a previously identified one, resulting in a missense amino acid substitution of D150N, but the substitution in FAD2B is a new one, resulting in H101D. The new amino acid substitution on FAD2B is located in the first histidine box (one of the active sites) of the fatty acid desaturase and may significantly decrease its activity. Our mutants did not have flowers on the main stem (subspecies hypogaea), but F435 (a previously identified natural high-oleate mutant) had flowers on the main stem (subspecies fastigiata). Therefore, we identified a class of natural mutants from the subspecies hypogaea and provided new additional genetic resources for breeders to use. Our results also demonstrate a good example of the importance and usefulness for preserving natural genetic diversity and utilizing plant germplasm collections.

Newly identified natural high-oleate mutant from Arachis hypogaea L. subsp. hypogaea

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Dave Pinnow

Author Tools

Chat about Author

Papers

Newly identified natural high-oleate mutant from Arachis hypogaea L. subsp. hypogaea