Genetic and biochemical approaches for studying the yellow stripe-like transporter family in plants.

Iron (Fe) is essential for plants but can be toxic if over-accumulated. Members of the yellow stripe-like (YSL) family of metal transporters play important roles in plant Fe homeostasis, and a great deal of evidence has been gathered over many years that indicates the importance of YSLs in the long distance transport of metals complexed with nicotianamine (NA). This review examines our current knowledge of YSLs, gleaned from both genetic and biochemical approaches. Many unanswered questions remain regarding the substrate specificities of these transporters, which seem to vary widely depending on the individual transporter. Data are also just beginning to become available regarding YSLs in the most basal clade, which may be responsible for intracellular transport of metal-NA complexes. Future research on YSL transporters should focus on utilizing the proven techniques of yeast complementation and Xenopus oocyte electrophysiology to examine the substrate specificity of YSLs in greater detail.