Expression and functional characterization of yellow stripe like transporters in hexaploid wheat

Abstract

YSL transporters are OPT family genes that are membrane-bound, transport multiple substrates including glutathione, small peptides, and metal chelated non-proteinaceous amino acids. YSL transporters have been reported from different plant species from both non-graminaceous and only a few from graminaceous species. Therefore, the YSL gene family surely needs investigation in hexaploid wheat. This study is first comprehensive inventory of OPT gene family in wheat. 26 wheat YSL genes corresponding to 67 homoeologs were identified. Expression profile of TaYSL genes under different nutrient starvation conditions showed their responsiveness to iron-deficiency and also suggested their broader range of substrates. Tissue-specific expression profile suggested their potential involvement in uptake and long-distance iron transport in wheat. Functional characterization in yeast showed iron transport by TaYS1A and TaYSL2. In planta validation of TaYS1A in Arabidopsis also provided evidence for its function in iron transport. The study fills in the knowledge gaps about iron transport mechanism in wheat. newline