Zhou Anqi, Kane Annalise, Wu Sheng, Wang Kaibiao, Santiago Michell, Ishiguro Yui, Yoneyama Kaori, Palayam Malathy, Shabek Nitzan, Xie Xiaonan, Nelson David C, Li Yanran
Aiiso Yufeng Li Family Department of Chemical and Nano Engineering, University of California, San Diego, CA, USA.
Department of Botany and Plant Sciences, University of California, Riverside, CA, USA.
Science. 2025 Jan 17;387(6731):eadp0779. doi: 10.1126/science.adp0779.
Strigolactones (SLs) are methylbutenolide molecules derived from β-carotene through an intermediate carlactonoic acid (CLA). Canonical SLs act as signals to microbes and plants, whereas noncanonical SLs are primarily plant hormones. The cytochrome P450 CYP722C catalyzes a critical step, converting CLA to canonical SLs in most angiosperms. Using synthetic biology, we investigated the function of , an evolutionary predecessor of . CYP722A converts CLA into 16-hydroxy-CLA (16-OH-CLA), a noncanonical SL detected exclusively in the shoots of various flowering plants. 16-OH-CLA application restores control of shoot branching to SL-deficient mutants in and is perceived by the SL signaling pathway. We hypothesize that biosynthesis of 16-OH-CLA by CYP722A was a metabolic stepping stone in the evolution of canonical SLs that mediate rhizospheric signaling in many flowering plants.
独脚金内酯（SLs）是一类甲基丁烯内酯分子，通过中间产物克拉罗内酯酸（CLA）由β-胡萝卜素衍生而来。典型的SLs对微生物和植物起信号作用，而非典型的SLs主要是植物激素。细胞色素P450 CYP722C催化关键步骤，在大多数被子植物中将CLA转化为典型的SLs。利用合成生物学，我们研究了CYP722A的进化前身CYP722A1的功能。CYP722A将CLA转化为16-羟基克拉罗内酯酸（16-OH-CLA），这是一种仅在各种开花植物的地上部分检测到的非典型SLs。施用16-OH-CLA可恢复拟南芥中SL缺陷型突变体对地上部分分枝的控制，并且可被SL信号通路感知。我们推测，CYP722A合成16-OH-CLA是许多开花植物中介导根际信号的典型SLs进化过程中的一个代谢踏脚石。
