Skip Navigation


JXB Advance Access originally published online on July 20, 2009
Journal of Experimental Botany 2009 60(12):3587-3594; doi:10.1093/jxb/erp203
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplementary Data
Right arrow All Versions of this Article:
60/12/3587    most recent
erp203v1
Right arrow E-letters: Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when E-letters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Sliwinska, E.
Right arrow Articles by Bewley, J. D.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Sliwinska, E.
Right arrow Articles by Bewley, J. D.
Agricola
Right arrow Articles by Sliwinska, E.
Right arrow Articles by Bewley, J. D.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author [2009]. Published by Oxford University Press [on behalf of the Society for Experimental Biology]. All rights reserved. For Permissions, please e-mail: journals.permissions@oxfordjournals.org

RESEARCH PAPER

Germination of Arabidopsis thaliana seeds is not completed as a result of elongation of the radicle but of the adjacent transition zone and lower hypocotyl

Elwira Sliwinska1,*, George W. Bassel2 and J. Derek Bewley3

1Department of Genetics and Plant Breeding, University of Technology and Life Sciences, 85-789 Bydgoszcz, Poland
2Department of Horticulture, Oregon State University, Corvallis, OR 97331-7304, USA
3Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada

* To whom correspondence should be addressed. E-mail: elwira{at}mail.utp.edu.pl

The completion of germination of seeds of Arabidopsis thaliana is marked by the appearance of the radicle through the surrounding endosperm and testa. Using confocal microscopy and green fluorescent protein (GFP)-transformed embryos to highlight the epidermal cell walls it has been possible to conduct time-lapse photography of individual embryos during their germination. This reveals that the elongation of embryo cells to effect completion of germination does not occur within the radicle itself, but rather within a discrete region that is immediately proximal to the radicle. This region, identifiable as the lower hypocotyl and hypocotyl–radicle transition zone, is also definable by accumulation of carbohydrate-containing bodies during germination, and distinct GFP expression of GAL4–GFP in enhancer trap lines. Flow cytometric studies show that there is an increase in the proportion of 4C nuclei in the axis which coincides with a considerable increase in length of the hypocotyl, and the occurrence of endopolyploid (8C and 16C) nuclei accompanies the 2-fold increase in mean cell size in the region of elongation, the lower hypocotyl, and hypocotyl–radicle transition zone. Thus the observed cell elongation during germination is accompanied by an increase in nuclear DNA content, and the resultant elongation of the axis to effect radicle emergence is due to cell expansion, not to cell division. When studying the molecular events involved in the completion of germination, therefore, it may be prudent to focus on this region of elongation.

Key words: Arabidopsis thaliana, cell cycle, cell elongation, DNA content, endoreduplication, germination, green fluorescent protein, hypocotyl, radicle, transition zone

Received 20 March 2009; Revised 22 May 2009 Accepted 28 May 2009


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.