A novel regulatory mechanism based upon a dynamic core structure for the mitochondrial pyruvate dehydrogenase complex?
The Arabidopsis thaliana genome includes three genes for mitochondrial dihydrolipoamide acetyltransferase, the E2-component of the mitochondrial pyruvate dehydrogenase complex (PDC). Two genes encode E2-proteins with a single lipoyl domain, while the third has a two-lipoyl domain structure. Transcripts for each E2 protein were expressed in all plant organs. Each recombinant AtmtE2 can individually form an icosahedral PDC core structure, and results from bimolecular fluorescence complementation assays are consistent with formation of hetero-core structures from all permutations of the AtmtE2 proteins. We propose a unique regulatory mechanism involving dynamic formation of hetero-core complexes that include both mono- and di-lipoyl forms of AtmtE2.
Department of Biochemistry, University of Missouri, Columbia, MO, USA. Electronic address: amandabroz@gmail.com.
Amanda K
AK
Broz
Department of Biochemistry, University of Missouri, Columbia, MO, USA.
Alejandro
A
Tovar-Méndez
Department of Biochemistry, University of Missouri, Columbia, MO, USA; Interdisciplinary Plant Group, University of Missouri, Columbia, MO, USA; Proteomics Center, University of Missouri, Columbia, MO, USA.
Brian P
BP
Mooney
USDA, Agricultural Research Service, Plant Genetics Research Unit, University of Missouri, Columbia, MO 65211, USA.
Mark L
ML
Johnston
Department of Biochemistry, University of Missouri, Columbia, MO, USA; Interdisciplinary Plant Group, University of Missouri, Columbia, MO, USA; USDA, Agricultural Research Service, Plant Genetics Research Unit, University of Missouri, Columbia, MO 65211, USA.
Jan A
JA
Miernyk
Department of Biochemistry, University of Missouri, Columbia, MO, USA; Interdisciplinary Plant Group, University of Missouri, Columbia, MO, USA. Electronic address: randalld@missouri.edu.
Douglas D
DD
Randall
D017360:Arabidopsis / Q000737:chemistry / Q000201:enzymology* / Q000378:metabolism; D051047:Dihydrolipoyllysine-Residue Acetyltransferase / Q000737:chemistry / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D046911:Macromolecular Substances / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D024101:Mitochondrial Proteins / Q000378:metabolism*; D055503:Protein Multimerization; D011768:Pyruvate Dehydrogenase Complex / Q000737:chemistry / Q000378:metabolism*
D046911:Macromolecular Substances; D024101:Mitochondrial Proteins; D011768:Pyruvate Dehydrogenase Complex; D051047:Dihydrolipoyllysine-Residue Acetyltransferase
BiFC; Protein interaction; Regulation; Structure; Transmission Electron Microscopy