NSF Postdoctoral Fellow, Department of Horticultural Science, University of Minnesota, 2014-2017
Postdoctoral Researcher, Department of Horticultural Science, University of Minnesota, 2013-present
Ph.D. Colorado State University, Fort Collins, CO; Biochemistry, 2014
B.A. College of St. Scholastica, Duluth, MN; Biochemistry, 2008
Mass spectrometry, Proteomics, Metabolomics, Turnover/Flux
Dr. Freund’s research focuses on mass spectrometry (MS)-based techniques to answer biochemical questions. Recently, she successfully adapted a method from ‘leaf-spray’ by Liu, Wang, Cooks, and Ouyang (2011), Anal Chem, 83: 7608-13. Direct leaf or tissue spray analysis can be used to study metabolites in vivo from many plant species and various tissue types. The technique is amenable to simultaneous collection of positive and negative polarity spectra and can provide fragmentation spectra often from a single sample. A variety of metabolites can be observed with this method including amino acids, polyphenols, carotenoids, alkaloids, carbohydrates and others (based on exact mass data). Direct tissue spray as a metabolomics technique eliminates sample pretreatment and preparation allowing for rapid sampling in real time of living intact tissue. Further method development will attempt to improve additional microsampling techniques for metabolomics and metabolic flux analysis in whole plants and single cells.
Current research efforts are being spent on using stable isotopic metabolic labeling in combination with mass spectrometry for both proteomics and metabolomics studies. The incorporation of a stable isotopic label (15N and/or 13C) allows for abundance changes in both proteins and metabolites to be measured. Studies are being conduct using Arabidopsis thaliana, a reference flowering plant as a model to explore the effect of reversible post-translational modifications (PTMs) on protein turnover and metabolite flux. The goal of this project is to make direct connections between protein function and stability, PTMs, and metabolite flux to increase our understanding of the regulation of plant metabolism. NSF NPGI Postdoctoral Fellowship in Biology FY 2014.