CRISPR/Cas9-Mediated Knockout of GmFATB1 Significantly Reduced the Amount of Saturated Fatty Acids in Soybean Seeds

Abstract

Soybean (Glycine max) oil is one of the most widely used vegetable oils across the world. Breeding of soybean to reduce the saturated fatty acid (FA) content, which is linked to cardiovascular disease, would be of great significance for nutritional improvement. Acyl-acyl carrier protein thioesterases (FATs) can release free FAs and acyl-ACP, which ultimately affects the FA profile. In this study, we identified a pair of soybean FATB coding genes, GmFATB1a and GmFATB1b. Mutants that knock out either or both of the GmFATB1 genes were obtained via CRISPR/Cas9. Single mutants, fatb1a and fatb1b, showed a decrease in leaf palmitic and stearic acid contents, ranging from 11% to 21%. The double mutant, fatb1a:1b, had a 42% and 35% decrease in palmitic and stearic acid content, displayed growth defects, and were male sterility. Analysis of the seed oil profile revealed that fatb1a and fatb1b had significant lower palmitic and stearic acid contents, 39–53% and 17–37%, respectively, while that of the unsaturated FAs were the same. The relative content of the beneficial FA, linoleic acid, was increased by 1.3–3.6%. The oil profile changes in these mutants were confirmed for four generations. Overall, our data illustrate that GmFATB1 knockout mutants have great potential in improving the soybean oil quality for human health.

Identification and Functional Characterization of Acyl-ACP Thioesterases B (GhFatBs) Responsible for Palmitic Acid Accumulation in Cotton Seeds

“…The other fatty acid profiles showed no significant changes. The similar situation was also observed in the GmFatB1 -overexpressed plants [ 41 ]. Theoretically, complex factors mediate fatty acid synthesis and accumulation in plant seeds.…”

Heat stress affects potato's volatile emissions that mediate agronomically important trophic interactions

“…We used scanning electron microscopy (SEM) to study the stomatal parameters from CT or HT plants as described previously (Ma et al, 2021). Leaf discs (0.385 mm 2 ) were punched out from plant leaves and fixed with 2.5% glutaraldehyde in phosphate buffer (pH 7.0, 0.1 M) for more than 4 h. The samples were washed three times in phosphate buffer (15 min each) and postfixed with 1% OsO 4 for 1-2 h and washed again with phosphate buffer completely.…”

Applications and prospects of genome editing in plant fatty acid and triacylglycerol biosynthesis

“…The 16:0-ACP, 18:0-ACP, and 18:1-ACP synthesized from plastids are converted to their free-acyl forms by FATB and FATA which are then released into the cytoplasm and converted into acyl-CoA ( Jones et al, 1995 ; Salas and Ohlrogge, 2002 ). Knockout of the FATB gene through CRISPR/Cas9 has been performed in soybean and peanut ( Table 2 ; Ma et al, 2021 ; Tang et al, 2022 ). Soybeans have four GmFATB proteins, all of which have at least 78% homology with Arabidopsis FATB at the protein level.…”

“…As a result of the simultaneous knockout of GmFATB1a and GmFATB1b expressed in seeds, the line in which both genes were disrupted showed male sterility. The SFA (palmitic acid and stearic acid) levels of the lines that lost only one of these two genes were 16–21%, but 32.2% in the wild type ( Ma et al, 2021 ). In peanuts, gRNA was designed to target both AhFATB10a and AhFATB10b , but only a mutation in AhFATB10a occurred, which decreased palmitic acid content by approximately 1%, which was slightly lower than that of the wild type (13.3%; Tang et al, 2022 ).…”