title: Bisphenol A affects germination and tube growth in Picea meyeri pollen through modulating Ca2+ flux and disturbing actin-dependent vesicular trafficking during cell wall construction.
abstract: Bisphenol A (BPA), a widespread pollutant, is reportedly harmful to humans, animals and plants. However, the effect of BPA on plant pollen tube growth, as well as the mechanism involved, remains unclear. Here, we report that BPA significantly inhibited Picea meyeri pollen germination and tube elongation in a dose-dependent manner. Transmission electron microscopy showed that BPA was detrimental to organelles such as mitochondria and Golgi apparatus. Non-invasive detection revealed that BPA inhibited extracellular Ca(2+) influx and promoted intracellular Ca(2+) efflux at the pollen tube tip, thereby inducing a dissipated Ca(2+) gradient. Fluorescence labeling showed that BPA disorganized actin filaments (AFs), which subsequently led to abnormal vesicle trafficking. Furthermore, BPA reduced the activity of acid phosphatase, a typical exocytosis enzyme. Moreover, Fourier transform infrared (FTIR) analysis and subsequent fluorescence labeling revealed that BPA induced an abnormal deposition of cell wall components, including pectins and callose. Taken together, our results indicate that BPA, a ubiquitous environmental pollutant, disturbs Ca(2+) flux in P. meyeri pollen tubes, thus disrupting AF organization, resulting in abnormal actin-dependent vesicle trafficking and further affecting the deposition of cell wall components. These findings provide new insight into the mechanism of BPA toxicity in pollen tube tip growth.
authors.affiliation: National Engineering Laboratory for Tree Breeding, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China.
authors.forename: Tongjie
authors.initials: T
authors.lastname: Chang
authors.affiliation: National Engineering Laboratory for Tree Breeding, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China.
authors.forename: Chengyu
authors.initials: C
authors.lastname: Fan
authors.affiliation: National Engineering Laboratory for Tree Breeding, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Man
authors.affiliation: National Engineering Laboratory for Tree Breeding, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China.
authors.forename: Junhui
authors.initials: J
authors.lastname: Zhou
authors.affiliation: National Engineering Laboratory for Tree Breeding, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China. Electronic address: ypjing@bjfu.edu.cn.
authors.forename: Yanping
authors.initials: Y
authors.lastname: Jing
mesh_terms: D000199:Actins / Q000378:metabolism*; D001559:Benzhydryl Compounds / Q000494:pharmacology*; D001693:Biological Transport, Active / Q000187:drug effects; D020013:Calcium Signaling / Q000187:drug effects*; D002473:Cell Wall / Q000378:metabolism; D022162:Cytoplasmic Vesicles / Q000378:metabolism*; D010636:Phenols / Q000494:pharmacology*; D028222:Picea / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism*; D053205:Pollen Tube / Q000254:growth & development*; D000098826:Bisphenol A Compounds
chemical_list: D000199:Actins; D001559:Benzhydryl Compounds; D010636:Phenols; D010940:Plant Proteins; C006780:bisphenol A; D000098826:Bisphenol A Compounds
keywords: Bisphenol A; Gymnosperm; Picea meyeri; Pollen germination; Pollen tube growth