APPROACHES TO CLONING GENES ENCODING FOR NUTRIENT TRANSPORTERS IN PLANTS

A number of strategies for identifying and cloning genes involved in n utrient transport and assimilation processes are discussed. Particular attention is paid to phenotypic screening by heterologous complementa tion of mutations which affect transport processes in other organisms and use of insertion elements in plant genomes. A program in which com plementation of yeast mutants is being used to clone genes involved in the uptake and assimilation of sulphate by plants is outlined. Inform ation is provided on the isolation of yeast mutants and their characte rization, choice of appropriate shuttle vectors, the construction of c DNA and genomic libraries, and screening of libraries for complementat ion.