Plant Cell Applied Biosystems SYBR(R) Cells-to-CT(TM) Kits
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

Plant Cell Advance Online Publication
Published on April 7, 2006; 10.1105/tpc.105.034041

This Article
Right arrow Full Text - TPC Advance Online Pub. (PDF)
Right arrow Supplemental Data
Right arrow All Versions of this Article:
18/5/1274    most recent
tpc.105.034041v1
Right arrow Alert me when this article is cited
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 Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Quattrocchio, F.
Right arrow Articles by Koes, R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Quattrocchio, F.
Right arrow Articles by Koes, R.
Agricola
Right arrow Articles by Quattrocchio, F.
Right arrow Articles by Koes, R.

Received May 11, 2005
Returned for revision March 8, 2006
Accepted March 18, 2006

PH4 of Petunia Is an R2R3 MYB Protein That Activates Vacuolar Acidification through Interactions with Basic-Helix-Loop-Helix Transcription Factors of the Anthocyanin Pathway

Francesca Quattrocchio 1, Walter Verweij 1, Arthur Kroon 1, Cornelis Spelt 1, Joseph Mol 1, and Ronald Koes 1*

1 Institute for Molecular and Cellular Biology, Vrije Universiteit, 1081 HV Amsterdam, The Netherlands

* To whom correspondence should be addressed. E-mail: ronald.koes{at}falw.vu.nl.

The Petunia hybrida genes ANTHOCYANIN1 (AN1) and AN2 encode transcription factors with a basic-helix-loop-helix (BHLH) and a MYB domain, respectively, that are required for anthocyanin synthesis and acidification of the vacuole in petal cells. Mutation of PH4 results in a bluer flower color, increased pH of petal extracts, and, in certain genetic backgrounds, the disappearance of anthocyanins and fading of the flower color. PH4 encodes a MYB domain protein that is expressed in the petal epidermis and that can interact, like AN2, with AN1 and the related BHLH protein JAF13 in yeast two-hybrid assays. Mutation of PH4 has little or no effect on the expression of structural anthocyanin genes but strongly downregulates the expression of CAC16.5, encoding a protease-like protein of unknown biological function. Constitutive expression of PH4 and AN1 in transgenic plants is sufficient to activate CAC16.5 ectopically. Together with the previous finding that AN1 domains required for anthocyanin synthesis and vacuolar acidification can be partially separated, this suggests that AN1 activates different pathways through interactions with distinct MYB proteins.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
ASPB Publications THE PLANT CELL PLANT PHYSIOLOGY
Copyright © 2006 by the American Society of Plant Biologists