Title: Mapping the ionome in Arabidopsis thaliana
Speaker: Dr. David E Salt, Purdue University, Department of Horticulture and Landscape Architecture
Place: KRAN G016; Tuesday, October 22, 2002, 4:30pm

Uptake and translocation of mineral nutrients in plants is essential for plant growth, human nutrition and health. In spite of recent advances in identifying genes involved in ion transport, the systems that control acquisition of individual ions remain largely unknown. In this project we are using inductively-coupled plasma mass spectrometry (ICP-MS) to help identify gene networks that control uptake and accumulation of a wide array of plant mineral nutrients and toxic metals. This information should lead to a better understanding of the way plants regulate their elemental content or "ionome". The approach involves the quantification of 18 elements including Li, Na, P, K, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Cd and Pb in 50-100 mutagenized Arabidopsis thaliana plants per day. Initially we have targeted fast neutron bombarded populations of which we have screened 4747 F2 individuals (approx. 20% of the genome) and rescreened 334 F3 putative mutants. From the putative mutants screened approximately 30% were confirmed to be mutant for at least 1 element. Statistical and visual data processing tools have been developed to assist in the analysis of data from over 12,500 plants analyzed to date. These tools are essential for the timely identification of mutants. A web-based database is also under construction to allow online access to the complete ICP-MS data set of over 230,000 data points for analysis by the plant community at large.