State Key Laboratory of Plant Diversity and Specialty Crops/State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Xiangshan, Beijing, 100093, China.
China National Botanical Garden, Beijing, 100093, China.
Planta. 2024 Sep 18;260(4):98. doi: 10.1007/s00425-024-04535-7.
The key genetic variation underlying the evo-devo of ICS in Solanaceae may be further pinpointed using an integrated strategy of forward and reverse genetics studies under the framework of phylogeny. The calyx of Physalis remains persistent throughout fruit development. Post-flowering, the fruiting calyx is inflated rapidly to encapsulate the berry, giving rise to a "Chinese lantern" structure called inflated calyx syndrome (ICS). It is unclear how this novelty arises. Over the past 2 decades, the role of MADS-box genes in the evolutionary development (evo-devo) of ICS has mainly been investigated within Solanaceae. In this review, we analyze the main achievements, challenges, and new progress. ICS acts as a source for fruit development, provides a microenvironment to protect fruit development, and assists in long-distance fruit dispersal. ICS is a typical post-floral trait, and the onset of its development is triggered by specific developmental signals that coincide with fertilization. These signals can be replaced by exogenous gibberellin and cytokinin application. MPF2-like heterotopic expression and MBP21-like loss have been proposed to be two essential evolutionary events for ICS origin, and manipulating the related MADS-box genes has been shown to affect the ICS size, sepal organ identity, and/or male fertility, but not completely disrupt ICS. Therefore, the core genes or key links in the ICS biosynthesis pathways may have undergone secondary mutations during evolution, or they have not yet been pinpointed. Recently, we have made some encouraging progress in acquiring lantern mutants in Physalis floridana. In addition to technological innovation, we propose an integrated strategy to further analyze the evo-devo mechanisms of ICS in Solanaceae using forward and reverse genetics studies under the framework of phylogeny.
ICS 在茄科植物进化发育中的关键遗传变异可以通过在系统发育框架内结合正向和反向遗传学研究的综合策略进一步确定。酸浆的花萼在整个果实发育过程中保持不变。开花后，果实花萼迅速膨胀，包裹浆果，形成一种称为膨胀花萼综合征 (ICS) 的“中国灯笼”结构。目前尚不清楚这种新颖性是如何产生的。在过去的 20 年中，MADS-box 基因在 ICS 的进化发育 (evo-devo) 中的作用主要在茄科植物中进行了研究。在这篇综述中，我们分析了主要的成果、挑战和新进展。ICS 作为果实发育的来源，为果实发育提供微环境，并有助于远距离果实传播。ICS 是一种典型的开花后特征，其发育的开始是由与受精同时发生的特定发育信号触发的。这些信号可以被外源赤霉素和细胞分裂素替代。MPF2 样异位表达和 MBP21 样缺失被提出是 ICS 起源的两个必要进化事件，并且操纵相关的 MADS-box 基因已被证明会影响 ICS 的大小、萼片器官身份和/或雄性育性，但不会完全破坏 ICS。因此，ICS 生物合成途径中的核心基因或关键环节可能在进化过程中发生了二次突变，或者尚未被确定。最近，我们在酸浆中获得了灯笼突变体方面取得了一些令人鼓舞的进展。除了技术创新，我们还提出了一种综合策略，即在系统发育框架内结合正向和反向遗传学研究，进一步分析茄科植物 ICS 的进化发育机制。
