PI: Christopher G. Taylor (Donald Danforth Plant Science Center) coPIs: Lauren McIntyre, Karen E. Koch (University of Florida; subawardee)
Intellectual Merit: The aim of this project is to define and characterize genes important in the development and function of transfer cells. Transfer cells facilitate the mass movement of sugars and amino acids from extracellular spaces to the inside of plant cells. For example, transfer cells are formed in endosperm tissues where assimilates are transferred from maternal tissues to the developing seed. Certain biotrophic interactions are also known to induce the formation of cells with similar function. Root-knot nematodes induce the formation of multinucleated cells, called giant cells, which serve as the exclusive source of nematode nutrition. Due to their functional similarities, transfer cells from seeds and nematode-induced giant cells share many of the same morphological characteristics including thickened and highly invaginated cell walls, dense cytoplasm, abundant ER, and numerous small vacuoles and mitochondria. Cells with transfer cell-like function are eminent objects of scientific interest since their activity involves a number of poorly understood molecular and cytological transport processes and they are crucial for the survival of both plants and specific biotrophic plant pathogens. Using laser capture microdissection, the transcriptome of transfer cells from developing seeds and from nematode-induced giant cells of Arabidopsis and maize will be examined for genes involved in transfer cell development and function. Genes unique and common to endosperm transfer cells and giant cells will be examined for their patterns of expression during plant development and nematode infestation. Sub-cellular localization of proteins will aid in assigning the role of proteins to transfer cell functions. T-DNA insertion lines (Arabidopsis) and transposon tagged lines (maize) will be used to examine the function of genes (and the proteins they encode) during seed development or nematode parasitism. Molecular and biochemical analysis of Arabidopsis and maize mutants will provide additional information on the role of transfer cells in assimilate movement. All research materials will be cataloged and described on a project website (www.danforthcenter.org/taylor/) and made available to the research community. These experiments will provide valuable insight into the molecular basis of giant and transfer cell function and will be of high practical relevance given the importance of root-knot nematodes as plant pathogens and the importance of transfer cells in the formation of seed, fruit and/or biomass.
Broader Impacts: Three approaches to broadening the impact of science will be provided in this project. First, summer undergraduate interns will get involved in the project through the summer REU internship program at the Danforth Center. This program is dedicated to fostering an interest and understanding in basic science among students with an emphasis on the recruitment of underrepresented minorities. Secondly, we will provide summer teacher fellowships through a Research Education for Teachers (RET) program. The participating science teacher benefits from the knowledge and experience provided by working in an active laboratory. Thirdly, this project will develop several DNA Microarray Traveling Trunks that teach high school students about microarrays and their uses. High school science teachers will be trained to use the trunk and develop and administer lesson plans based on microarray technology. The Trunk program will incorporate lesson plans, equipment, materials, online resources and hands-on student activities to demonstrate the principals of microarrays. The Trunks will be shared among the school districts, reaching a diverse array of students across the St. Louis and surrounding areas.
