1
|
Flores-Tornero M, Wang L, Potěšil D, Hafidh S, Vogler F, Zdráhal Z, Honys D, Sprunck S, Dresselhaus T. Comparative analyses of angiosperm secretomes identify apoplastic pollen tube functions and novel secreted peptides. PLANT REPRODUCTION 2021; 34:47-60. [PMID: 33258014 PMCID: PMC7902602 DOI: 10.1007/s00497-020-00399-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 11/10/2020] [Indexed: 05/14/2023]
Abstract
KEY MESSAGE Analyses of secretomes of in vitro grown pollen tubes from Amborella, maize and tobacco identified many components of processes associated with the cell wall, signaling and metabolism as well as novel small secreted peptides. Flowering plants (angiosperms) generate pollen grains that germinate on the stigma and produce tubes to transport their sperm cells cargo deep into the maternal reproductive tissues toward the ovules for a double fertilization process. During their journey, pollen tubes secrete many proteins (secreted proteome or secretome) required, for example, for communication with the maternal reproductive tissues, to build a solid own cell wall that withstands their high turgor pressure while softening simultaneously maternal cell wall tissue. The composition and species specificity or family specificity of the pollen tube secretome is poorly understood. Here, we provide a suitable method to obtain the pollen tube secretome from in vitro grown pollen tubes of the basal angiosperm Amborella trichopoda (Amborella) and the Poaceae model maize. The previously published secretome of tobacco pollen tubes was used as an example of eudicotyledonous plants in this comparative study. The secretome of the three species is each strongly different compared to the respective protein composition of pollen grains and tubes. In Amborella and maize, about 40% proteins are secreted by the conventional "classic" pathway and 30% by unconventional pathways. The latter pathway is expanded in tobacco. Proteins enriched in the secretome are especially involved in functions associated with the cell wall, cell surface, energy and lipid metabolism, proteolysis and redox processes. Expansins, pectin methylesterase inhibitors and RALFs are enriched in maize, while tobacco secretes many proteins involved, for example, in proteolysis and signaling. While the majority of proteins detected in the secretome occur also in pollen grains and pollen tubes, and correlate in the number of mapped peptides with relative gene expression levels, some novel secreted small proteins were identified. Moreover, the identification of secreted proteins containing pro-peptides indicates that these are processed in the apoplast. In conclusion, we provide a proteome resource from three distinct angiosperm clades that can be utilized among others to study the localization, abundance and processing of known secreted proteins and help to identify novel pollen tube secreted proteins for functional studies.
Collapse
Affiliation(s)
- María Flores-Tornero
- Cell Biology and Plant Biochemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Lele Wang
- Cell Biology and Plant Biochemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - David Potěšil
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, Kamenice 5, 62500, Brno, Czech Republic
| | - Said Hafidh
- Laboratory of Pollen Biology, Institute of Experimental Botany ASCR, Rozvojová 263, 165 02, Prague 6, Czech Republic
| | - Frank Vogler
- Cell Biology and Plant Biochemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Zbyněk Zdráhal
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, Kamenice 5, 62500, Brno, Czech Republic
| | - David Honys
- Laboratory of Pollen Biology, Institute of Experimental Botany ASCR, Rozvojová 263, 165 02, Prague 6, Czech Republic
| | - Stefanie Sprunck
- Cell Biology and Plant Biochemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Thomas Dresselhaus
- Cell Biology and Plant Biochemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany.
| |
Collapse
|
2
|
Joly V, Tebbji F, Nantel A, Matton DP. Pollination Type Recognition from a Distance by the Ovary Is Revealed Through a Global Transcriptomic Analysis. PLANTS (BASEL, SWITZERLAND) 2019; 8:E185. [PMID: 31238522 PMCID: PMC6630372 DOI: 10.3390/plants8060185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 06/09/2019] [Accepted: 06/12/2019] [Indexed: 02/06/2023]
Abstract
Sexual reproduction in flowering plants involves intimate contact and continuous interactions between the growing pollen tube and the female reproductive structures. These interactions can trigger responses in distal regions of the flower well ahead of fertilization. While pollination-induced petal senescence has been studied extensively, less is known about how pollination is perceived at a distance in the ovary, and how specific this response is to various pollen genotypes. To address this question, we performed a global transcriptomic analysis in the ovary of a wild potato species, Solanum chacoense, at various time points following compatible, incompatible, and heterospecific pollinations. In all cases, pollen tube penetration in the stigma was initially perceived as a wounding aggression. Then, as the pollen tubes grew in the style, a growing number of genes became specific to each pollen genotype. Functional classification analyses revealed sharp differences in the response to compatible and heterospecific pollinations. For instance, the former induced reactive oxygen species (ROS)-related genes while the latter affected genes associated to ethylene signaling. In contrast, incompatible pollination remained more akin to a wound response. Our analysis reveals that every pollination type produces a specific molecular signature generating diversified and specific responses at a distance in the ovary in preparation for fertilization.
Collapse
Affiliation(s)
- Valentin Joly
- Institut de Recherche en Biologie Végétale, Université de Montréal, Montréal, QC H1X 2B2, Canada.
| | - Faïza Tebbji
- CRCHU de Québec, Université Laval, Québec, QC G1V 4G2, Canada.
| | - André Nantel
- National Research Council Canada, Montréal, QC H4P 2R2, Canada.
| | - Daniel P Matton
- Institut de Recherche en Biologie Végétale, Université de Montréal, Montréal, QC H1X 2B2, Canada.
| |
Collapse
|