[Wolfgang Schmidt] When too much ain’t enough: The biology of iron-overaccumulating genotypes
POST:
On account of its competence to accept and donate electrons, iron is an essential element across all forms of life, including plants. Maintaining Fe homeostasis requires precise orchestration of its uptake, trafficking and translocation in order to meet the demand of Fe sinks such as plastids. Plants harboring defects in the systemic Fe transporter OLIGOPEPTIDE TRANSPORTER 3 display constitutive iron deficiency responses and accumulate toxic levels of iron in their leaves. Similarly, ectopic expression of IRONMAN genes, encoding a family of phloem-localized signaling peptides, triggers the uptake and accumulation of iron by compromising the iron sensor BRUTUS. By comparing the transcriptional landscapes of these lines, the groups of Louis Grillet at NTU and Wolfgang Schmidt at IPMB discovered that two plastid-encoded tRNA-derived small RNAs are involved in retrograde control of root iron uptake. The data have been recently published in The Plant Genome, a journal of the Crop Science Society of America.