title: Cytological and Proteomic Analyses of Osmunda cinnamomea Germinating Spores Reveal Characteristics of Fern Spore Germination and Rhizoid Tip Growth.
abstract: Fern spore is a good single-cell model for studying the sophisticated molecular networks in asymmetric cell division, differentiation, and polar growth. Osmunda cinnamomea L. var. asiatica is one of the oldest fern species with typical separate-growing trophophyll and sporophyll. The chlorophyllous spores generated from sporophyll can germinate without dormancy. In this study, the spore ultrastructure, antioxidant enzyme activities, as well as protein and gene expression patterns were analyzed in the course of spore germination at five typical stages (i.e. mature spores, rehydrated spores, double-celled spores, germinated spores, and spores with protonemal cells). Proteomic analysis revealed 113 differentially expressed proteins, which were mainly involved in photosynthesis, reserve mobilization, energy supplying, protein synthesis and turnover, reactive oxygen species scavenging, signaling, and cell structure modulation. The presence of multiple proteoforms of 25 differentially expressed proteins implies that post-translational modification may play important roles in spore germination. The dynamic patterns of proteins and their encoding genes exhibited specific characteristics in the processes of cell division and rhizoid tip growth, which include heterotrophic and autotrophic metabolisms, de novo protein synthesis and active protein turnover, reactive oxygen species and hormone (brassinosteroid and ethylene) signaling, and vesicle trafficking and cytoskeleton dynamic. In addition, the function skew of proteins in fern spores highlights the unique and common mechanisms when compared with evolutionarily divergent spermatophyte pollen. These findings provide an improved understanding of the typical single-celled asymmetric division and polar growth during fern spore germination.
authors.affiliation: From the ‡Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Harbin 150040, China;
authors.forename: Jinwei
authors.initials: J
authors.lastname: Suo
authors.affiliation: From the ‡Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Harbin 150040, China;
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: From the ‡Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Harbin 150040, China;
authors.forename: Zhengxiu
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: ‖Department of Biology, Genetics Institute, Plant Molecular and Cellular Biology Program, Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, Florida 32610;
authors.forename: Sixue
authors.initials: S
authors.lastname: Chen
authors.affiliation: ¶College of Life and Environmental Sciences, Shanghai Normal University, Shanghai, 200234, China;
authors.forename: Jian'guo
authors.initials: J
authors.lastname: Cao
authors.affiliation: §State Key Laboratory of Tree Genetics and Breeding (Northeast Forestry University), School of Forestry, Northeast Forestry University, Harbin 150040, China;
authors.forename: Guanjun
authors.initials: G
authors.lastname: Liu
authors.affiliation: §State Key Laboratory of Tree Genetics and Breeding (Northeast Forestry University), School of Forestry, Northeast Forestry University, Harbin 150040, China;
authors.forename: Xing
authors.initials: X
authors.lastname: Wei
authors.affiliation: **Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Tai
authors.initials: T
authors.lastname: Wang
authors.affiliation: §State Key Laboratory of Tree Genetics and Breeding (Northeast Forestry University), School of Forestry, Northeast Forestry University, Harbin 150040, China;
authors.forename: Chuanping
authors.initials: C
authors.lastname: Yang
authors.affiliation: From the ‡Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Harbin 150040, China; §State Key Laboratory of Tree Genetics and Breeding (Northeast Forestry University), School of Forestry, Northeast Forestry University, Harbin 150040, China; daishaojun@hotmail.com.
authors.forename: Shaojun
authors.initials: S
authors.lastname: Dai
mesh_terms: D018506:Gene Expression Regulation, Plant; D018525:Germination; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D029621:Polypodiaceae / Q000254:growth & development* / Q000502:physiology / Q000648:ultrastructure*; D040901:Proteomics / Q000379:methods; D059010:Single-Cell Analysis; D013170:Spores / Q000254:growth & development / Q000648:ultrastructure
chemical_list: D010940:Plant Proteins