| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
BOTANICAL BRIEFING |
How Many Genes are Needed to Make a Pollen Tube? Lessons from Transcriptomics
1 Centro de Biologia do Desenvolvimento, Instituto Gulbenkian de Ciência, PT-2780–156 Oeiras, Portugal
2 Universidade de Lisboa, Faculdade de Ciências, Dept. Biologia Vegetal, Campo Grande, C2, PT-1749-016 Lisboa, Portugal
* For correspondence. E-mail jfeijo{at}fc.ul.pt
Received: 30 January 2007 Returned for revision: 9 March 2007 Accepted: 2 July 2007
Background: Pollen is the male gametophyte of higher plants. Upon pollination, it germinates and develops into a fast-growing cytoplasmic extension, the pollen tube, which ultimately delivers the sperm into the ovary. The biological relevance of its role, and the uniqueness of this kind of cellular organization, have made pollen the focus of many approaches, and it stands today as one of the best-known models in plant cell biology. In contrast, the genetic background of its development has been until recently largely unknown. Some genes involved have been described and a few functional mutants have been characterized, but only to a limited extent and allowing only a limited understanding of the regulatory mechanisms. Yet, being a relatively simple organ (2 or 3 cells), pollen stands as an excellent target for molecular-biology-based approaches.
Recent Progress: Recent studies on Arabidopsis thaliana have characterized the transcriptional profile of pollen grains and microgametogenesis in comparison to sporophytic tissues. They underline the unique characteristics of pollen, not only in terms of a strongly reduced set of genes being expressed, but also in terms of the functions of the proteins encoded and the pathways they are involved in. These approaches have expanded the number of genes with known expression in pollen from a few hundred to nearly eight thousand. While for the first time allowing systems and/or gene-family approaches, this information also expands dramatically the possibility of hypothesis-driven experimentation based on specific gene function predictions. Recent studies reveal this to be the case in, for example, transcriptional regulation, cell-cycle progression and gene-silencing mechanisms in mature pollen.
Key words: Pollen, transcriptome, proteome, microarray, Arabidopsis
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  R. Grant-Downton, S. Hafidh, D. Twell, and H. G. Dickinson Small RNA Pathways Are Present and Functional in the Angiosperm Male Gametophyte Mol Plant, May 1, 2009; 2(3): 500 - 512. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Borg, L. Brownfield, and D. Twell Male gametophyte development: a molecular perspective J. Exp. Bot., April 1, 2009; 60(5): 1465 - 1478. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Wang, W.-Z. Zhang, L.-F. Song, J.-J. Zou, Z. Su, and W.-H. Wu Transcriptome Analyses Show Changes in Gene Expression to Accompany Pollen Germination and Tube Growth in Arabidopsis Plant Physiology, November 1, 2008; 148(3): 1201 - 1211. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Borges, G. Gomes, R. Gardner, N. Moreno, S. McCormick, J. A. Feijo, and J. D. Becker Comparative Transcriptomics of Arabidopsis Sperm Cells Plant Physiology, October 1, 2008; 148(2): 1168 - 1181. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. D. Russell, P. L. Bhalla, and M. B. Singh Transcriptome-Based Examination of Putative Pollen Allergens of Rice (Oryza sativa ssp. japonica) Mol Plant, September 1, 2008; 1(5): 751 - 759. [Abstract] [Full Text] [PDF]
|
|