Campus Units

Biochemistry, Biophysics and Molecular Biology, Roy J. Carver Department of, Center for Biorenewable Chemicals, Center for Metabolic Biology

Document Type

Article

Publication Version

Published Version

Publication Date

6-2020

Journal or Book Title

Plant Physiology

Volume

183

Issue

2

First Page

547

Last Page

557

DOI

10.1104/pp.19.01468

Abstract

Acyl carrier protein (ACP) is a highly conserved cofactor protein that is required by Type II fatty acid synthases (FASs). Here, we demonstrate that up to three mitochondrial ACP (mtACP) isoforms support the Arabidopsis (Arabidopsis thaliana) mitochondrially localized Type II FAS. The physiological importance of the three mtACPs was evaluated by characterizing the single, double, and triple mutants. The mtACP1 (At2g44620), mtACP2 (At1g65290), and mtACP3 (At5g47630) single mutants showed no discernible morphological growth phenotype. Functional redundancy among the three mtACPs was indicated by the embryo-lethal phenotype associated with simultaneous loss of all three mtACP genes. Characterization of all double mutant combinations revealed that although the mtacp1 mtacp3 and mtacp2 mtacp3 double mutant combinations showed no observable growth defect, the mtacp1 mtacp2 double mutant was viable but displayed delayed growth, reduced levels of posttranslationally lipoylated mitochondrial proteins, hyperaccumulation of photorespiratory Gly, and reduced accumulation of many intermediates in central metabolism. These alterations were partially reversed when the mtacp1 mtacp2 double mutant plants were grown in a nonphotorespiratory condition (i.e. 1% CO2 atmosphere) or in the presence of 2% Suc. In summary, mtACP, as a key component of mitochondrial fatty acid biosynthesis, is important in generating the fatty acid precursor of lipoic acid biosynthesis. Thus, the incomplete lipoylation of mitochondrial proteins in mtacp mutants, particularly Gly decarboxylase, affects the recovery of photorespiratory carbon, and this appears to be critical during embryogenesis.

Comments

This article is published as Fu, Xinyu, Xin Guan, Rachel Garlock, and Basil J. Nikolau. "Mitochondrial fatty acid synthase utilizes multiple acyl carrier protein isoforms." Plant physiology 183, no. 2 (2020): 547-557. doi:10.1104/pp.19.01468.

Creative Commons License

Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.

Copyright Owner

American Society of Plant Biologists

Language

en

File Format

application/pdf

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