Skip Navigation



JXB Advance Access published online on December 21, 2006

Journal of Experimental Botany, doi:10.1093/jxb/erl264
This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
58/5/1025    most recent
erl264v1
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 Yin, Y.
Right arrow Articles by Ashihara, H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Yin, Y.
Right arrow Articles by Ashihara, H.
Agricola
Right arrow Articles by Yin, Y.
Right arrow Articles by Ashihara, H.
Social Bookmarking
 Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author [2006]. 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

Involvement of rapid nucleotide synthesis in recovery from phosphate starvation of Catharanthus roseus cells

Yuling Yin1, Fusako Shimano1 and Hiroshi Ashihara1,2,*

1Department of Advanced Bioscience, Graduate School of Humanities and Sciences, Ochanomizu University, Tokyo, 112-8610 Japan
2Metabolic Biology Group, Department of Biology, Faculty of Science, Ochanomizu University, Tokyo, 112-8610 Japan

* To whom correspondence should be addressed. E-mail: ashihara.hiroshi{at}ocha.ac.jp

Growth of suspension-cultured Catharanthus roseus cells ceased during phosphate starvation, but the cells grew again upon addition of Pi even after long-term starvation. The metabolic fate of [33P]Pi was studied in 1-week-old stationary phase cells in ordinary culture and in 1- or 2-week-old Pi-starved cells. Immediately after administration, the most heavily labelled organic compounds are nucleotides, followed by sugar phosphates. Two weeks Pi starvation slowed down the speed of incorporation of 33P into nucleotides. The RNA, protein, and free nucleotide content all decreased gradually during Pi starvation; however, these compounds, especially nucleotides, increased markedly in the 24 h after addition of Pi. These responses are found in all cells examined, although the total amounts of these compounds were lower in the long-term Pi-deficient cells. Of the nucleotides, a marked increase was observed in nucleoside triphosphates and UDP-glucose. The transcript level of phosphate transporter and the activities of acid phosphatase, 5'- and 3'-nucleotidase, and adenosine nucleosidase were all reduced by the addition of Pi. In contrast, the activities of adenine phosphoribosyltransferase, nicotinate phosphoribosyltransferase, and nicotinamidase, which are salvage enzymes of purine and pyridine nucleotides, were markedly increased in the Pi-fed cells. Little or no increase was observed in adenosine kinase. In the light of these results, the possible involvement of net nucleotide synthesis in the initial metabolic events of recovery from Pi deficiency are discussed.

Key words: Adenine nucleotide, cultured cell, metabolic regulation, nucleotide biosynthesis, phosphate starvation, salvage pathway


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.