Wang Yikui, Liu Ake, Li Wenjia, Jiang Yaqing, Song Shiwei, Li Yan, Chen Riyuan
College of Horticulture, South China Agricultural University, Guangzhou, China.
Institute of Vegetable Research, Guangxi Academy of Agricultural Sciences, Nanning, China.
PLoS One. 2017 Jun 6;12(6):e0179018. doi: 10.1371/journal.pone.0179018. eCollection 2017.
Heterostyly is a common floral polymorphism, but the proteomic basis of this trait is still largely unexplored. In this study, self- and cross-pollination of L-morph and S-morph flowers and comparison of embryo sac development in eggplant (Solanum melongena L.) suggested that lower fruit set from S-morph flowers results from stigma-pollen incompatibility. To explore the molecular mechanism underlying heterostyly development, we conducted isobaric tags for relative and absolute quantification (iTRAQ) proteomic analysis of eggplant pistils for L- and S-morph flowers. A total of 5,259 distinct proteins were identified during heterostyly development. Compared S-morph flowers with L-morph, we discovered 57 and 184 differentially expressed proteins (DEPs) during flower development and maturity, respectively. Quantitative real time polymerase chain reactions were used for nine genes to verify DEPs from the iTRAQ approach. During flower development, DEPs were mainly involved in morphogenesis, biosynthetic processes, and metabolic pathways. At flower maturity, DEPs primarily participated in biosynthetic processes, metabolic pathways, and the formation of ribosomes and proteasomes. Additionally, some proteins associated with senescence and programmed cell death were found to be upregulated in S-morph pistils, which may lead to the lower fruit set in S-morph flowers. Although the exact roles of these related proteins are not yet known, this was the first attempt to use an iTRAQ approach to analyze proteomes of heterostylous eggplant flowers, and these results will provide insights into biochemical events taking place during the development of heterostyly.
花柱异长是一种常见的花多态性，但该性状的蛋白质组学基础仍 largely unexplored。在本研究中，茄子（Solanum melongena L.）的长花柱型和短花柱型花朵的自花授粉和异花授粉以及胚囊发育比较表明，短花柱型花朵较低的坐果率是由柱头 - 花粉不亲和导致的。为了探究花柱异长发育的分子机制，我们对茄子长花柱型和短花柱型花朵的雌蕊进行了相对和绝对定量（iTRAQ）蛋白质组分析。在花柱异长发育过程中总共鉴定出5259种不同的蛋白质。将短花柱型花朵与长花柱型花朵相比，我们分别在花朵发育和成熟阶段发现了57种和184种差异表达蛋白（DEP）。使用实时定量聚合酶链反应对9个基因进行验证，以确认来自iTRAQ方法的DEP。在花朵发育过程中，DEP主要参与形态发生、生物合成过程和代谢途径。在花朵成熟时，DEP主要参与生物合成过程、代谢途径以及核糖体和蛋白酶体的形成。此外，发现一些与衰老和程序性细胞死亡相关的蛋白质在短花柱型雌蕊中上调，这可能导致短花柱型花朵较低的坐果率。尽管这些相关蛋白质的确切作用尚不清楚，但这是首次尝试使用iTRAQ方法分析花柱异长茄子花的蛋白质组，这些结果将为花柱异长发育过程中发生的生化事件提供见解。
