Abstract
Iodine is a scarce yet crucial element in the human diet. Iodine is involved in human neurological and physical development by acting as a key component of thyroid hormones. Insufficient iodine intake results in various Iodine Deficiency Disorders (IDDs), which affect billions of people. A relevant strategy to increase iodine levels in humans include the prophylactic consumption of iodized salt, but additional and combinatory strategies are necessary to successfully mitigate this global problem. Recently, the development of iodine biofortified crops has been discussed as a promising strategy to combat IDDs. In plants, iodine is considered a beneficial element for plant growth and the response to environmental stress. Regardless of its importance, assimilation and mode-of-action of iodine at the plant molecular level are still not understood. Based on a comparative genomics strategy, we have established several parallelisms for iodine regulation between plants and non-plant organisms. Here, we will explore a gene family involved in the homeostatic control of iodine in plants. A phylogenetic overview will highlight the degree of conservation of this gene family in plants. To explore the importance of these genes in iodine content regulation, Arabidopsis T-DNA insertion mutants and overexpression lines will be established for functional genomics analysis. A developmental map of these lines will be performed and Arabidopsis seedlings will be subjected to varying concentrations of iodine. The impact of these treatments will be studied through the analysis of morphology/physiology parameters and the iodine content quantification will be indicative of the thresholds for iodine biofortification and tolerance in plants.