Liu Han, Wang Jing, Wen Zhaodi, Qin Mei, Lu Ying, Huang Lirong, Ou Xialian, Kang Liang, Li Cui, Lei Ming, Zhang Zhanjiang
Guangxi Key Laboratory of Medicinal Resources Protection and Genetic Improvement, Guangxi Botanical Garden of Medicinal Plants, Nanning 530023, China.
National Center for Traditional Chinese Medicine Inheritance and Innovation, Guangxi Botanical Garden of Medicinal Plants, Nanning 530023, China.
Plants (Basel). 2025 Jun 27;14(13):1974. doi: 10.3390/plants14131974.
Annexins (ANNs) are a family of calcium (Ca)-dependent and phospholipid-binding proteins, which are implicated in the regulation of plant growth and development as well as protection from biotic and abiotic stresses. Bunting, an endangered benzylisoquinoline alkaloid (BIA)-rich herbaceous plant, widely used in traditional Chinese medicine, is endemic to the calciphilic karst region of China. However, whether and how ANNs are involved in the biosynthesis pathway of BIAs and/or help plants cope with abiotic properties, such as calcareous soils, are largely unknown. Here, nine genes were identified from , and they were divided into three subfamilies, namely subfamilies I, II, and IV, based on the phylogenetic tree. The CsANNs clustered into the same clade, sharing similar gene structures and conserved motifs. The nine genes were located on five chromosomes, and their expansions were mainly attributed to tandem and whole-genome duplications. The transcripts displayed organ-specific and Ca-responsive expression patterns across various tissues. In addition, transient overexpression assays showed that CsANN1 could positively regulate the accumulation of BIA compounds in leaves, probably by directly interacting with key BIA-biosynthetic-pathway enzymes or by interacting with BIA-biosynthetic regulatory factors, such as MYBs. This study sheds light on the profiles and functions of the gene family and paves the way for unraveling the molecular mechanism of BIA accumulation, which is regulated by Ca through CsANNs.
膜联蛋白（ANNs）是一类依赖钙（Ca）且能结合磷脂的蛋白质家族，参与植物生长发育的调控以及抵御生物和非生物胁迫。黄藤，一种濒临灭绝的富含苄基异喹啉生物碱（BIA）的草本植物，广泛应用于传统中药，是中国嗜钙喀斯特地区的特有植物。然而，ANNs是否以及如何参与BIA的生物合成途径和/或帮助植物应对诸如石灰性土壤等非生物特性，目前 largely unknown。在此，从[具体来源]中鉴定出九个基因，基于系统发育树将它们分为三个亚家族，即亚家族I、II和IV。CsANNs聚在同一分支，具有相似的基因结构和保守基序。这九个基因位于五条染色体上，它们的扩增主要归因于串联重复和全基因组重复。这些转录本在不同组织中呈现器官特异性和钙响应表达模式。此外，瞬时过表达分析表明，CsANN1可能通过直接与BIA生物合成途径的关键酶相互作用或与BIA生物合成调节因子（如MYBs）相互作用，正向调节[具体植物名称]叶片中BIA化合物的积累。本研究揭示了[具体植物名称]基因家族的概况和功能，为阐明由Ca通过CsANNs调控的BIA积累的分子机制铺平了道路。
