We are beginning to understand
how inositol lipid biosynthesis is regulated in plants and what
cellular processes are intertwined with the metabolism of phosphoinositides.
Research in our laboratory is focused on elucidating regulation
of the inositol lipid kinases and their role in limiting the
flux through the phosphoinositide (PI) pathway in plants. We
have developed molecular and biochemical tools to study the
inositol lipid kinases in vivo and in vitro. Our specific aims
are to understand how plasma membrane and other cellular PtdIns4P
and PtdIns(4,5)P2 pools are generated and how these pools affect
plant responses to a changing environment. This research is
currently funded by the National Science Foundation and in part
by the NC Agricultural Research Service.
Redesigning Plants For Increased Stress
Tolerance Using Genes From Extremophiles:
The second major project began with a focus on synthetic biology. The project was funded by the NASA Institute for Advanced Concepts. Our goal was to redesign plants to withstand increased stress by expressing genes from extremophiles. This is a collaborative project with Dr. Amy Grunden in Microbiology. We have expressed in plants one of three superoxide reductase (SOR) pathway genes from Pyrococcus furiosus. The SOR pathway is a more effective and efficient pathway for removing reactive oxygen species (ROS) than the endogenous, plant pathways and the SOR pathway enzymes are functional over a broad temperature range (4-100 oC). Our hypothesis is that the P. furiosus enzymes will enhance stress tolerance by rapidly removing the ROS. We have shown that plant can express P. furiosus superoxide reductase and produce a functional enzyme and that Arabidopsis plants producing SOR are more tolerant of heat and high light (Im et al., FEBS Letts 579:5521-5526, 2005; Im et al., Plant Physiology, 151: 893-904, 2009). We have extended the work from Arabidopsis to a crop plant, tomatoes. This project funded by the USDA. Our hypothesis is that expressing SOR in a crop plant will not only enhance heat and light tolerance but also decrease the diversion of metabolites to secondary metabolism and thereby enhance biomass production under stressful conditions.
We are currently using these and other synthetic systems that we have generated to characterize the long term impact of altering basal signaling on plant stress responses. The project included teaching an honors course entitled “Redesigning Life for Mars.” Publicity concerning the project and an interview by Bob McDonald on the CBC radio show “Quirks and Quarks” can be found at the following web sites.
Life for Mars - Tulips on the Moon
This research has been supported in part by the USDA NSF,
DOE, and the
Agricultural Research Service.