| Title: | A petunia chorismate mutase specialized for the production of floral volatiles |
| Author(s): | Colquhoun TA; Schimmel BC; Kim JY; Reinhardt D; Cline K; Clark DG; |
| Address: | "Department of Environmental Horticulture, and Plant Molecular and Cellular Biology, University of Florida, Gainesville, FL 32611, USA" |
| DOI: | 10.1111/j.1365-313X.2009.04042.x |
| ISSN/ISBN: | 1365-313X (Electronic) 0960-7412 (Print) 0960-7412 (Linking) |
| Abstract: | "In Petunia x hybrida cv. 'Mitchell Diploid' floral fragrance is comprised of 13 volatile benzenoids/phenylpropanoids derived from the aromatic amino acid phenylalanine. Several genes involved in the direct synthesis of individual floral volatile benzenoid/phenylpropanoid (FVBP) compounds, i.e. at the end of the pathway, have been isolated and characterized in petunia through reverse genetic and biochemical approaches. In an effort to understand the regulation of 'upstream' components in the FVBP system, we have cloned and characterized two CHORISMATE MUTASE (PhCM1 and PhCM2) cDNAs from petunia. PhCM1 has a transcript accumulation profile consistent with known FVBP genes, while PhCM2 showed a constitutive transcript accumulation profile. The plastid-localized PhCM1 is allosterically regulated by tryptophan but not phenylalanine or tyrosine. The total FVBP emission in PhCM1 RNAi knockdown petunias is reduced by approximately 60-70%, and total chorismate mutase activity in corolla tissue is reduced by 80-85% compared to control plants. These results show that PhCM1 is the principal CHORISMATE MUTASE responsible for the coupling of metabolites from the shikimate pathway to the synthesis of FVBPs in the corolla of Petunia x hybrida cv. 'Mitchell Diploid'" |
| Keywords: | "Benzene Derivatives/chemistry/metabolism Chorismate Mutase/genetics/*physiology Flowers/*metabolism Gene Expression Regulation, Plant/genetics/physiology Models, Biological Petunia/*enzymology Plant Proteins/genetics/*physiology Propanols/chemistry/metabo;" |
| Notes: | "MedlineColquhoun, Thomas A Schimmel, Bernardus C J Kim, Joo Young Reinhardt, Didier Cline, Kenneth Clark, David G eng R01 GM046951/GM/NIGMS NIH HHS/ R01 GM046951-18/GM/NIGMS NIH HHS/ R01 GM46951/GM/NIGMS NIH HHS/ Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. England 2009/10/09 Plant J. 2010 Jan; 61(1):145-55. doi: 10.1111/j.1365-313X.2009.04042.x. Epub 2009 Oct 7" |
