Kathrin Schrick, Associate Professor
303 Ackert Hall
Lab website: http://www.k-state.edu/schricklab
Ph.D. 1994, University of Washington. Genetics.
Area(s) of Specialization
Plant Molecular Biology, Developmental Biology, Plant Evolution, START Domains, Plant Sterols.
Plants and plant-derived products such as food, fiber, fuel, and medicines, are vital to life on earth. Many of these resources rely on plant-specific biochemical reactions involving proteins and lipid metabolites. Direct interactions between proteins and small molecules are dynamic in all living cells, yet their full extent and biological significance is underexplored, especially in plants. We use genetics and molecular approaches in the model system Arabidopsis to study protein-metabolite interactions involving sterols and other metabolic lipids in the context of plant growth and development.
START domains in plants
Candidate lipid/sterol-binding proteins include transcription factors of the class III and IV homeodomain leucine-zipper (HD-Zip) family. These plant-specific regulatory proteins contain a StAR-related lipid transfer (START) domain, named after mammalian steroidogenic acute regulatory protein orthologs (StARs). In humans, misexpression of several START domain proteins is associated with cancer. It is hypothesized that START domains link lipid/sterol metabolism to the cell division cycle. We are studying the role of START domains in class IV HD-Zip transcription factors that are critical for differentiation of the epidermis. Related to this, we are investigating relevant evolutionary mechanisms that led to the emergence of the land plants from the Charophycean green algae ~450 million years ago.
Sterols in development and in cell wall biogenesis
Another research focus is on the functions of sterols and their glycosylated forms in plants. Sterol biosynthesis enzymes are differentially expressed throughout development and sterol contents vary temporally and spatially according to cell type. Sterol production may reflect the metabolic state of cells, which in turn is exploited to regulate developmental processes. Sterols are also important as structural features of cell membranes. Our discovery that sterol biosynthesis is crucial for cellulose production suggests a mechanism by which sterols influence cell wall biogenesis. One proposed model suggests that glycosylated sterols act as primers in cellulose synthesis, by supplying glucose residues to growing microfibrils. We are characterizing UDP-glucose:sterol glucosyltransferase mutants of Arabidopsis to address this hypothesis. If specific steryl glucosides and/or sterols are critical for cellulose synthesis, their modulation may yield improved cellulose production in biomass crops.
Msanne, J., Chen, M., Luttgeharm, K., Bradley, A.M., Mays, E.S., Paper, J.M., Boyle, D.L., Cahoon, R.E., Schrick, K., and Cahoon, E.B. 2015. Glucosylceramide is critical for cell-type differentiation and organogenesis, but not for cell viability in Arabidopsis. Plant J. 84:188-201.
Stucky, D.F., Arpin, J.C., and Schrick, K. 2015. Functional diversification of two UGT80 enzymes required for steryl glucoside synthesis in Arabidopsis. J. Exp. Bot. 66:189-201.
Schrick, K., Bruno, M., Khosla, A., Cox, P.N., Marlatt, S.A., Roque, R.A., Nguyen, H.C., He, C., Snyder, M.P., Singh, D., and Yadav, G. 2014. Shared functions of plant and mammalian StAR-related lipid transfer (START) domains in modulating transcription factor activity. BMC Biology 12:70. doi:10.1186/s12915-014-0070-8.
Khosla, A., Paper, J.M., Boehler, A.P., Bradley, A.M., Neumann, T.R., and Schrick, K. 2014. HD-Zip proteins GL2 and HDG11 have redundant functions in Arabidopsis trichomes and Gl2 activates a positive feedback loop via MYB23. Plant Cell 26:2184-2200.
Schrick, K., DeBolt, S., and Bulone, V. 2012. Deciphering the molecular functions of sterols in cellulose biosynthesis. Front. Plant Sci. 3:84. doi: 10.3389/fpls.2012.00084
Schrick, K., Shiva, S., Arpin, J.C., Delimont, N., Isaac, G., Tamura, P. and Welti, R. 2012. Steryl glucoside and acyl steryl glucoside analysis of Arabidopsis seeds by electrospray ionization tandem mass spectrometry. Lipids 47:185-193.
Schrick, K., Cordova, C., Li, G., Murray, L. and Fujioka, S. 2011. A dynamic role for sterols in embryogenesis of Pisum sativum. Phytochemistry 72: 465-475.
View the complete publication list in NCBI