Chalcone synthase (CHS) is the key enzyme in the flavonoid biosynthetic pathway and has been studied in many plants, but the function of the CHS gene has not been well characterized in Paeonia ostii. In this study, we obtained a CHS homologue gene from P. ostii, which possessed the putative conserved amino acids of chalcone synthase by multiple alignment analysis and demonstrated the highest expression in developing seeds. In vitro assays of the recombinant PoCHS protein confirmed enzymatic activity using malonyl-CoA and 4-coumaroyl-CoA as substrates, and the optimal pH and reaction temperature were 7.5 and 40°C, respectively. Furthermore, ectopic over-expression of PoCHS in Arabidopsis up-regulated the expression levels of genes involved in seed development (ABI), glycolysis (PKp2, PDH-E1a, and SUS2/3), and especially fatty acid biosynthesis (BCCP2, CAC2, CDS2, FatA and FAD3). This resulted in an increased unsaturated fatty acid content, especially α-linolenic acid, in transgenic Arabidopsis seeds. In this study, we examined the functions of CHS homologue in P. ostii and demonstrated its new function in seed fatty acid biosynthesis. This article is protected by copyright. All rights reserved.

中文翻译：

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芍药中 PoCHS 的生态过度表达改变了拟南芥中的脂肪酸组成和含量

查尔酮合酶 (CHS) 是类黄酮生物合成途径中的关键酶，已在许多植物中进行了研究，但 CHS 基因的功能尚未在芍药中得到很好的表征。在本研究中，我们从 P. ostii 中获得了一个 CHS 同源基因，该基因通过多重比对分析具有推定的查尔酮合酶保守氨基酸，并证明在发育种子中表达最高。重组 PoCHS 蛋白的体外测定证实了酶活性，使用丙二酰辅酶 A 和 4-香豆酰辅酶 A 作为底物，最佳 pH 值和反应温度分别为 7.5 和 40°C。此外，拟南芥中 PoCHS 的异位过表达上调了种子发育（ABI）、糖酵解（PKp2、PDH-E1a 和 SUS2/3）相关基因的表达水平，尤其是脂肪酸生物合成（BCCP2、CAC2、CDS2、FatA 和 FAD3）。这导致转基因拟南芥种子中不饱和脂肪酸含量增加，尤其是α-亚麻酸。在这项研究中，我们检查了 P. ostii 中 CHS 同源物的功能，并证明了其在种子脂肪酸生物合成中的新功能。本文受版权保护。版权所有。