全基因组复制(WGD)事件在植物和动物中普遍存在,因此,它们的长期进化贡献长期以来一直被推测,然而,具体的贡献很难验证。这里,我们表明,通过各自祖先的活性BR生物合成酶和活性BR受体的创新,作为真正的油菜素类固醇(BR)信号的起源和进化。我们发现BR受体BRI1(BRInsensitive1)和BRL1/3(BRI1-likes1/3)由♪-WGD和ζ-WGD衍生,发生在被子植物和种子植物的共同祖先中,分别,而孤儿BR受体BRL2首先出现在口腔真菌中。此外,CYP85A酶合成来自种子植物共同祖先的生物活性BR,而其姊妹酶CYP90合成BR前体存在于所有陆地植物中,暗示可能的配体-受体协同进化。始终如一,BR受体中负责BR感知的岛域(ID)在不同受体分支之间差异最大,支持配体驱动的进化。因此,BRI1是被子植物中最多样化的BR受体。重要的是,相对于所有陆地植物中存在的BR生物合成DET2基因,BRL2、BRL1/3和BRI1在维管植物蕨类植物中高表达,裸子植物和被子植物,分别。值得注意的是,BRI1是最多样化的BR受体,在被子植物中表达最丰富,暗示潜在的积极选择。因此,WGD通过配体感知和转录表达启动了一个新功能化过程,这可能会优化BR生物合成酶和BR受体,可能有助于陆地植物的进化,尤其是种子植物和被子植物。
Whole genome duplication (WGD) events are widespread in plants and animals, thus their long-term evolutionary contribution has long been speculated, yet a specific contribution is difficult to verify. Here, we show that ɛ-WGD and ζ-WGD contribute to the origin and evolution of bona fide brassinosteroid (BR) signaling through the innovation of active BR biosynthetic enzymes and active BR receptors from their respective ancestors. We found that BR receptors BRI1 (BR Insensitive 1) and BRL1/3 (BRI1-likes 1/3) derived by ɛ-WGD and ζ-WGD, which occurred in the common ancestor of angiosperms and seed plants, respectively, while orphan BR receptor BRL2 first appeared in stomatophytes. Additionally, CYP85A enzymes synthesizing the bioactive BRs derived from a common ancestor of seed plants while its sister enzymes CYP90 synthesizing BR precursors presented in all land plants, implying possible ligand-receptor coevolution. Consistently, the island domains (IDs) responsible for BR perception in BR receptors were most divergent among different receptor branches, supporting ligand-driven evolution. As a result, BRI1 was the most diversified BR receptor in angiosperms. Importantly, relative to the BR biosynthetic DET2 gene presented in all land plants, BRL2, BRL1/3 and BRI1 had high expression in vascular plants ferns, gymnosperms and angiosperms, respectively. Notably, BRI1 is the most diversified BR receptor with the most abundant expression in angiosperms, suggesting potential positive selection. Therefore, WGDs initiate a neofunctionalization process diverged by ligand-perception and transcriptional expression, which might optimize both BR biosynthetic enzymes and BR receptors, likely contributing to the evolution of land plants, especially seed plants and angiosperms.