Kim Kihwan, Park Jiyoung, Norah Nabachwa, Kim Sooyeon, Jo Hyun, Song Jong Tae, Lee Jeong-Dong
Upland Field Machinery Research Center, Kyungpook National University, Daegu, 41566, Republic of Korea.
Department of Applied Biosciences, Kyungpook National University, Daegu, 41566, Republic of Korea.
BMC Plant Biol. 2025 Jul 2;25(1):818. doi: 10.1186/s12870-025-06836-9.
Soybean is an extensively utilized oilseed crop, and improved cultivars and cultivation efficiency of soybean have contributed to the increased use of soybean in edible oil applications. The food industry necessitates the development of soybean oil with an optimized balance of polyunsaturated and saturated fatty acids to meet both nutritional requirements and industrial applications.
This study aimed to elucidate the protein structure and functional characterization of a novel allele of derived from an EMS-induced mutant line and assess its potential as a genetic resource for developing soybean cultivars with elevated saturated fatty acid composition. Sequence variation in the gene was evaluated for PE1544 (~ 16.1% palmitic acid composition), an EMS-induced mutant with high-palmitic acid. A single-nucleotide polymorphism was identified in the gene of PE1544, resulting in an amino acid substitution from Gly309 to Asp309. Comparative analysis of three-dimensional protein structures revealed that Gly309 plays a critical role in stabilizing the catalytic residue in the KASII-A active site. Co-segregation analysis revealed that the novel allele was recessive to and was associated with high-palmitic acid composition. Furthermore, we analyzed the F population derived from the cross between the high-stearic acid line with homozygous recessive allele and PE1544. The F progeny with both mutations exhibited a lower stearic acid composition compared to the single mutant. Notably, the F progeny with both mutations exhibited a similar ratio of polyunsaturated to saturated fatty acids (P/S index) compared to the single mutant. These findings suggest that regulates the palmitic acid and stearic acid composition regardless of the total composition of saturated fatty acids in the single mutant. Comprehensively, the regulation of in the single mutant is effective for the development of soybean oil with an ideal P/S index by regulating the content of palmitic and stearic acid while maintaining high-saturated fatty acids.
These results suggest that the conversion of palmitic acid to stearic acid is impaired due to the loss-of-function of KASII-A, indicating that the novel allele of plays a crucial role in this biochemical conversion in soybean.
The online version contains supplementary material available at 10.1186/s12870-025-06836-9.
大豆是一种广泛种植的油料作物，改良品种和提高种植效率促进了大豆在食用油领域的更多应用。食品工业需要开发一种多不饱和脂肪酸和饱和脂肪酸比例优化的大豆油，以满足营养需求和工业应用。
本研究旨在阐明源自EMS诱变突变系的一个新等位基因的蛋白质结构和功能特性，并评估其作为培育饱和脂肪酸含量升高的大豆品种的遗传资源的潜力。对PE1544（棕榈酸含量约16.1%）这个高棕榈酸含量的EMS诱变突变体的基因序列变异进行了评估。在PE1544的基因中鉴定出一个单核苷酸多态性，导致氨基酸从Gly309替换为Asp309。三维蛋白质结构的比较分析表明，Gly309在稳定KASII-A活性位点的催化残基方面起关键作用。共分离分析表明，这个新等位基因对是隐性的，并且与高棕榈酸含量相关。此外，我们分析了高硬脂酸纯合隐性等位基因系与PE1544杂交产生的F群体。与单个突变体相比，具有两种突变的F后代硬脂酸含量较低。值得注意的是，与单个突变体相比，具有两种突变的F后代多不饱和脂肪酸与饱和脂肪酸的比例（P/S指数）相似。这些发现表明，无论单个突变体中饱和脂肪酸的总组成如何，都能调节棕榈酸和硬脂酸的组成。综合来看，单个突变体中的调控通过调节棕榈酸和硬脂酸含量同时保持高饱和脂肪酸，对于开发具有理想P/S指数的大豆油是有效的。
这些结果表明，由于KASII-A功能丧失，棕榈酸向硬脂酸的转化受到损害，表明的新等位基因在大豆的这种生化转化中起关键作用。
在线版本包含可在10.1186/s12870-025-06836-9获取的补充材料。
