Yang Hanbing, Wei Xiuqing, Wang Lifeng, Zheng Ping, Li Junzhang, Zou Yutong, Wang Lulu, Feng Xinyuan, Xu Jiahui, Qin Yuan, Zhuang Yuhui
College of Life Sciences, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
Fruit Research Institute, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China.
Int J Mol Sci. 2025 Mar 6;26(5):2348. doi: 10.3390/ijms26052348.
Passion fruit (), mainly distributed in tropical and subtropical regions, is popular for its unique flavor and health benefits. The actin cytoskeleton plays a crucial role in plant growth and development, and villin is a key regulator of actin dynamics. However, the mechanism underlying the actin filament regulation of reproductive development in passion fruit remains poorly understood. Here, we characterized a villin isovariant in passion fruit, (), highly and preferentially expressed in pollen. Subcellular localization analysis showed that PeVLN4 decorated distinct filamentous structures in pollen tubes. We next introduced into mutants to explore its functions on the growing pollen tubes. rescued defects in the elongation of mutant pollen tubes. Pollen tubes expressing were revealed to be less sensitive to latrunculin B, and partially rescued defects in the actin filament organization of mutant pollen tubes. Additionally, biochemical assays revealed that PeVLN4 bundles actin filaments in vitro. Thus, PeVLN4 is an important regulator of F-actin stability and is required for normal pollen tube growth in passion fruit. This study provides a new insight into the function of the actin regulator villin involved in the reproduction development of passion fruit.
西番莲主要分布在热带和亚热带地区，因其独特的风味和对健康的益处而广受欢迎。肌动蛋白细胞骨架在植物生长发育中起关键作用，而绒毛蛋白是肌动蛋白动力学的关键调节因子。然而，西番莲中肌动蛋白丝调节生殖发育的机制仍知之甚少。在这里，我们鉴定了西番莲中的一种绒毛蛋白同工型（PeVLN4），它在花粉中高度且优先表达。亚细胞定位分析表明，PeVLN4在花粉管中形成独特的丝状结构。接下来，我们将PeVLN4导入拟南芥突变体中，以探究其对生长中的花粉管的功能。PeVLN4挽救了拟南芥突变体花粉管伸长的缺陷。表达PeVLN4的花粉管对Latrunculin B的敏感性较低，并且PeVLN4部分挽救了拟南芥突变体花粉管肌动蛋白丝组织的缺陷。此外，生化分析表明，PeVLN4在体外能使肌动蛋白丝成束。因此，PeVLN4是F-肌动蛋白稳定性的重要调节因子，是西番莲正常花粉管生长所必需的。本研究为参与西番莲生殖发育的肌动蛋白调节因子绒毛蛋白的功能提供了新的见解。
