Targeting of the Arabidopsis Homomeric Acetyl-Coenzyme A Carboxylase to Plastids of Rapeseeds
Open Access
- 1 January 1997
- journal article
- Published by Oxford University Press (OUP) in Plant Physiology
- Vol. 113 (1) , 75-81
- https://doi.org/10.1104/pp.113.1.75
Abstract
Acetyl-coenzyme A carboxylase (ACCase) occurs in at least two forms in rapeseed (Brassica napus): a homomeric (HO) and presumably cytosolic isozyme and a heteromeric, plastidial isozyme. We investigated whether the HO-ACCase of Arabidopsis can be targeted to plastids of B. napus seeds. A chloroplast transit peptide and the napin promoter were fused to the Arabidopsis ACC1 gene and transformed into B. napus, with the following results. (a) The small subunit transit peptide was sufficient to provide import of this very large protein into developing seed plastids. (b) HO-ACCase in isolated plastids was found to be biotinylated at a level comparable to extraplastidial HO-ACCase. (c) In vitro assays of HO-ACCase in isolated plastids from developing seeds indicate that it occurs as an enzymatically active form in the plastidial compartment. (d) ACCase activity in mature B. napus seeds is normally very low; however, plants expressing the SSU/ACC1 gene had 10- to 20-fold higher ACCase activity in mature seeds, suggesting that plastid localization prevents the turnover of HO-ACCase. (e) ACCase over-expression altered seed fatty acid composition, with the largest effect being an increase in oleic acid. (f) The total oil content of seeds was increased approximately 5% by the expression of HO-ACCase in plastids.Keywords
This publication has 15 references indexed in Scilit:
- Acetyl-CoA carboxylase exerts strong flux control over lipid synthesis in plantsPublished by Elsevier ,2002
- Acetyl-CoA Carboxylase in Higher Plants: Most Plants Other Than Gramineae Have Both the Prokaryotic and the Eukaryotic Forms of This EnzymePlant and Cell Physiology, 1996
- The Compartmentation of Acetyl-Coenzyme A Carboxylase in PlantsPlant Physiology, 1995
- Modification of Brassica napus seed oil by expression of the Escherichia coli fabH gene, encoding 3-ketoacyl-acyl carrier protein synthase IIIPlant Molecular Biology, 1995
- A Gene Encoding Acetyl-Coenzyme A Carboxylase from Brassica napusPlant Physiology, 1994
- Isolation of cDNAs from Brassica napus encoding the biotin-binding and transcarboxylase domains of acetyl-CoA carboxylase: assignment of the domain structure in a full-length Arabidopsis thaliana genomic cloneBiochemical Journal, 1994
- Localization and characterization of two structurally different forms of acetyl-CoA carboxylase in young pea leaves, of which one is sensitive to aryloxyphenoxypropionate herbicides.1994
- Structure and Expression of an Arabidopsis Acetyl-Coenzyme A Carboxylase GenePlant Physiology, 1994
- Developmental patterns of free and protein-bound biotin during maturation and germination of seeds of Pisum sativum: characterization of a novel seed-specific biotinylated proteinBiochemical Journal, 1994
- Plants contain multiple biotin enzymes: Discovery of 3-methylcrotonyl-CoA carboxylase, propionyl-CoA carboxylase and pyruvate carboxylase in the plant kingdomArchives of Biochemistry and Biophysics, 1990