Subcellular localization of rice acyl-CoA-binding proteins (ACBPs) indicates that OsACBP6::GFP is targeted to the peroxisomes.

Abstract

Acyl-CoA-binding proteins (ACBPs) show conservation at the acyl-CoA-binding (ACB) domain which facilitates binding to acyl-CoA esters. In Arabidopsis thaliana, six ACBPs participate in development and stress responses. Rice (Oryza sativa) also contains six genes encoding ACBPs. We investigated differences in subcellular localization between monocot rice and eudicot A. thaliana ACBPs. The subcellular localization of the six OsACBPs was achieved via transient expression of green fluorescence protein (GFP) fusions in tobacco (Nicotiana tabacum) epidermal cells, and stable transformation of A. thaliana. As plant ACBPs had not been reported in the peroxisomes, OsACBP6::GFP localization was confirmed by transient expression in rice sheath cells. The function of OsACBP6 was investigated by overexpressing 35S::OsACBP6 in the peroxisomal abc transporter1 (pxa1) mutant defective in peroxisomal fatty acid β-oxidation. As predicted, OsACBP1::GFP and OsACBP2::GFP were localized to the cytosol, and OsACBP4::GFP and OsACBP5::GFP to the endoplasmic reticulum (ER). However, OsACBP3::GFP displayed subcellular multi-localization while OsACBP6::GFP was localized to the peroxisomes. 35S::OsACBP6-OE/pxa1 lines showed recovery in indole-3-butyric acid (IBA) peroxisomal β-oxidation, wound-induced VEGETATIVE STORAGE PROTEIN1 (VSP1) expression and jasmonic acid (JA) accumulation. These findings indicate a role for OsACBP6 in peroxisomal β-oxidation, and suggest that rice ACBPs are involved in lipid degradation in addition to lipid biosynthesis.

• Authors: Wei Meng, An-Shan Hsiao, Caiji Gao, Liwen Jiang, Mee-Len Chye
• Journal: The New phytologist (New Phytol) Vol. 203 Issue 2 Pg. 469-482 (Jul 2014) ISSN: 1469-8137 [Electronic] England
• PMID: 24738983 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

Chemical References

• Arabidopsis Proteins
• Carrier Proteins
• Cyclopentanes
• Indoles
• Oxylipins
• Plant Proteins
• indolebutyric acid
• Green Fluorescent Proteins
• jasmonic acid

Topics

• Arabidopsis (genetics, metabolism)
• Arabidopsis Proteins (genetics, metabolism)
• Carrier Proteins (genetics, metabolism)
• Cyclopentanes (metabolism)
• Cytosol (metabolism)
• Green Fluorescent Proteins (genetics, metabolism)
• Indoles (metabolism)
• Lipid Metabolism (genetics)
• Oryza (genetics, metabolism)
• Oxylipins (metabolism)
• Peroxisomes (genetics, metabolism)
• Plant Proteins (genetics, metabolism)
• Plants, Genetically Modified
• Protein Transport
• Tobacco (genetics)