|BS||Chemistry||South Dakota State University||Brookings, S.D.|
|PhD||Biochemistry||Michigan State University||East Lansing, Mich.|
Metabolism, signal transduction, protein kinases and phosphorylated proteins in plants.
Randall is retired and no longer accepting graduate or postdoctoral students and his research program has ended.
Our group studied regulation of metabolism in plants, in particular, the pyruvate dehydrogenase complex (PDC) as a primary site at which photosynthetic carbon metabolism interacts with mitochondrial respiration and photorespiration. The regulation of this multienzyme complex has several layers including covalent modification by reversible phosphorylation (inactivation/deactivation). The regulation of the pyruvate dehydrogenase complex provides a site to manage the flow of carbon to the mitochondria during photosynthesis. Another form of this multienzyme complex is located in plastids where it functions in fatty acid and oil biosynthesis by providing the precursor acetyl-CoA for fatty acid, oil synthesis and a number of plant growth regulatory compounds. The final project was focused on solving the bottleneck in the production of biodegradable plastic in plants by engineering components of PDC and related complexes that metobolize branded chair ketoacids.
Related projects included the molecular characterization of the component subunits of the pyruvate dehydrogenase complex and how these subunits are imported into the organelle and assembled into the complex. We also charcterized plant protein kinases and identified their endogenous substrates. Protein kinases are essential components of many signal transduction pathways. Our group was part of a multi-institutional genomics project involving plant protein phosphorylation.
Notable Honors and Service
- American Association for the Advancement of Science, Fellow, 2008
- American Society of Plant Biologists, Fellow (2007), Board of Trustees Chair (1996-99), Secretary (1991-93)
- Thomas Jefferson Professor and Fellow, University of Missouri System
- Founder and Director, Interdisciplinary Plant Group, 1990-2008
- Member, National Science Board (2002-2014; Presidential appointment)
- Protein Expression and Purification Editorial Board (previous)
- Ann. Rev. Plant Physiology & Plant Molecular Biology Editorial Board (previous)
- Plant Physiology Editorial Board (previous)
- Biomedical Archives Editorial Board (previous)
- Current Topics in Plant Biochemistry & Physiology Symposium Series, Editor-in-Chief (previous)
Broz AK, Tovar-Méndez A, Mooney BP, Johnston ML, Miernyk JA, Randall DD. (2014). A novel regulatory mechanism based upon a dynamic core structure for the mitochondrial pyruvate dehydrogenase complex? Mitochondrion. 19 Pt B:144-53. doi: 10.1016/j.mito.2014.05.003. [PubMed]
Hirani TA, Tovar-Méndez A, Miernyk JA, Randall DD. (2011). Asp295 stabilizes the active-site loop structure of pyruvate dehydrogenase, facilitating phosphorylation of ser292 by pyruvate dehydrogenase-kinase. Enzyme Res. 2011:939068. doi: 10.4061/2011/939068. [PubMed]
Huang Y, Houston NL, Tovar-Mendez A, Stevenson SE, Miernyk JA, Randall DD, Thelen JJ. (2010). A quantitative mass spectrometry-based approach for identifying protein kinase clients and quantifying kinase activity. Anal Biochem. 402(1):69-76. doi: 10.1016/j.ab.2010.03.028. [PubMed]
Tovar-Méndez A, Hirani TA, Miernyk JA, Randall DD. (2005). Analysis of the catalytic mechanism of pyruvate dehydrogenase kinase. Arch Biochem Biophys. 434(1):159-68. [PubMed]
Tovar-Méndez A, Miernyk JA, Randall DD. (2003). Regulation of pyruvate dehydrogenase complex activity in plant cells. Eur J Biochem. 270(6):1043-9. [PubMed]
Mooney BP, Miernyk JA, Randall DD. (2002). The complex fate of alpha-ketoacids. Annu Rev Plant Biol. 53:357-75. Review. [PubMed]