|BS||Bowling Green State University||Bowling Green, Ohio||Biology / Chemistry|
|PhD||University of Texas||Austin, Texas||Microbiology / Botany|
Host-microbe interactions. The major focus of research in the Stacey lab is the symbiosis between the bacterium Bradyrhizobium japonicum and its host plant, soybean. The result of this interaction is the establishment of a novel organ, nodule, on the root of the host. Inside this organ, B. japonicum fixes atmospheric nitrogen, which the plant can utilize. Our work on this symbiosis focuses both on the symbiont and the plant host. With regard to the bacterium, we are largely focusing on functional genomics of the symbiont and the identification of key functions necessary for the symbiosis. Plant perception of lipo-chitin nodulation signals, produced by the bacterium, is essential for induction of de novo organogenesis, leading to nodule formation. Our research is focused on plant recognition of this molecule and the signal transduction pathways leading to nodule development. This work led to a general interest in plant chitin signaling and the identification of the plant receptor for chitin recognition. We are now exploring the role of this receptor and the downstream signaling pathway and how it relates to the induction of plant innate immunity.
Extracellular ATP. Our lab is one of the few in the world exploring the role of extracellular ATP as a signal in plants. Extracellular ATP is well studied in animal system where it has been shown to be involved in a variety of processes (e.g., nerve function, muscle contraction, inflammation, etc.). Our focus is on the identification of the plant receptor for eATP and understanding the downstream signaling pathway. Our data suggests that eATP is essential for normal plant growth and development. Hence, understanding the function of this important signal is key to understanding how plants grow.
Peptide transport in plants. There is a growing body of information implicating peptides as circulating hormones in plants. This is consistent with the major role that peptides play in regulating growth and development in animals. Our contribution to this area focuses on the role of peptide transporters in the growth and development of the model plant Arabidopsis thaliana. We have identified peptide transporters in two families: PTR, which transport di- and tripeptides and OPT, which transport tetra- and pentapeptides. In both cases, disruption of peptide transporter expression (e.g., through antisense expression or mutation) results in severe defects in seed and embryo development. Our goal in this research is to define the role peptide transporters play in plant growth and development, to define their substrates and to elucidate the regulation of these interesting proteins.
Soybean genomics and biotechnology. As part of the growing family of researchers at MU who are interested in soybean biology, our laboratory is contributing to the development of soybean genomic research. The goal of this research is to identify genes and traits, which can benefit soybean agriculture. For example, our lab was a key member of the consortium that recently completed the soybean genome sequence. We are currently working on tools for mutagenesis so that we can study soybean gene function.
Tanaka K, Nguyen CT, Liang Y, Cao Y, Stacey G. Role of LysM receptors in chitin-triggered plant innate immunity. Plant Signal Behav. 2012 Dec 6;8(1).
Cui Y, Barampuram S, Stacey MG, Hancock CN, Findley S, Mathieu M, Zhang Z, Parrott WA, Stacey G. Tnt1 retrotransposon mutagenesis: a tool for soybean functional genomics. Plant Physiol. 2013 Jan;161(1):36-47. doi: 10.1104/pp.112.205369. Epub 2012 Nov 1.
Radwan O, Wu X, Govindarajulu M, Libault M, Neece DJ, Oh MH, Berg RH, Stacey G, Taylor CG, Huber SC, Clough SJ. 14-3-3 proteins SGF14c and SGF14l play critical roles during soybean nodulation. Plant Physiol. 2012 Dec;160(4):2125-36. doi: 10.1104/pp.112.207027. Epub 2012 Oct 11.
Brechenmacher L, Nguyen TH, Hixson K, Libault M, Aldrich J, Pasa-Tolic L, Stacey G. Identification of soybean proteins from a single cell type: the root hair. Proteomics. 2012 Nov;12(22):3365-73. doi: 10.1002/pmic.201200160.
Roulin A, Auer PL, Libault M, Schlueter J, Farmer A, May G, Stacey G, Doerge RW, Jackson SA. The fate of duplicated genes in a polyploid plant genome. Plant J. 2012 Sep 14. doi: 10.1111/tpj.12026.