Abstract
Expression of AtFRO2 is controlled by promotive signals sent from whole plant to roots under iron deficient condition. On the other hand, the expression of AtbHLH38 is likely regulated by local signals in roots, because the expression is not influenced by leaf-excision. It is showed that AtbHLH38 interacts with AtFIT, and these complex induces the expression of AtFRO2. Therefore, we hypothesize that the long-ditance signal regulated the expression of AtFRO2 via AtFIT which interact with AtbHLH38.
We performed microarray analysis of the iron deficiency response in roots to identify genes which involve in the regulation of iron uptake in roots. Seedlings were grown under iron sufficient or deficient condition, and their roots were harvested 24 hours after all leaves were cut or not cut. The result suggested that 36 genes were influenced by the long distance signals and 43 genes were regulated by the local signals.