Comprehensive analysis of tobacco pollen transcriptome unveils common pathways in polar cell expansion and underlying heterochronic shift during spermatogenesis

BMC Plant Biology

Research Article

Jana Feciková¹  Petr Růžička¹  Věra Čapková¹  Said Hafidh¹  Katarína Breznenová¹  David Honys² 

[1] Laboratory of Pollen Biology, Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Rozvojová 263, 165 02, Praha 6, Czech Republic;Laboratory of Pollen Biology, Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Rozvojová 263, 165 02, Praha 6, Czech Republic;Department of Plant Experimental Biology, Faculty of Science, Charles University in Prague, Viničná 5, 128 44, Praha 2, Czech Republic;

关键词: Gene Ontology;    Germ Cell;    Pollen Tube;    Sperm Cell;    Pollen Germination;   

DOI  :  10.1186/1471-2229-12-24

 received in 2011-09-22, accepted in 2012-02-16,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundMany flowering plants produce bicellular pollen. The two cells of the pollen grain are destined for separate fates in the male gametophyte, which provides a unique opportunity to study genetic interactions that govern guided single-cell polar expansion of the growing pollen tube and the coordinated control of germ cell division and sperm cell fate specification. We applied the Agilent 44 K tobacco gene chip to conduct the first transcriptomic analysis of the tobacco male gametophyte. In addition, we performed a comparative study of the Arabidopsis root-hair trichoblast transcriptome to evaluate genetic factors and common pathways involved in polarized cell-tip expansion.ResultsProgression of pollen grains from freshly dehisced anthers to pollen tubes 4 h after germination is accompanied with > 5,161 (14.9%) gametophyte-specific expressed probes active in at least one of the developmental stages. In contrast, > 18,821 (54.4%) probes were preferentially expressed in the sporophyte. Our comparative approach identified a subset of 104 pollen tube-expressed genes that overlap with root-hair trichoblasts. Reverse genetic analysis of selected candidates demonstrated that Cu/Zn superoxide dismutase 1 (CSD1), a WD-40 containing protein (BP130384), and Replication factor C1 (NtRFC1) are among the central regulators of pollen-tube tip growth. Extension of our analysis beyond the second haploid mitosis enabled identification of an opposing-dynamic accumulation of core regulators of cell proliferation and cell fate determinants in accordance with the progression of the germ cell cycle.ConclusionsThe current study provides a foundation to isolate conserved regulators of cell tip expansion and those that are unique for pollen tube growth to the female gametophyte. A transcriptomic data set is presented as a benchmark for future functional studies using developing pollen as a model. Our results demonstrated previously unknown functions of certain genes in pollen-tube tip growth. In addition, we highlighted the molecular dynamics of core cell-cycle regulators in the male gametophyte and postulated the first genetic model to account for the differential timing of spermatogenesis among angiosperms and its coordination with female gametogenesis.

【 授权许可】

Unknown   
© Hafidh et al; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.