AUTHOR=Verma Pankaj K. , Verma Shikha , Pande Veena , Mallick Shekhar , Deo Tripathi Rudra , Dhankher Om P. , Chakrabarty Debasis 

TITLE=Overexpression of Rice Glutaredoxin OsGrx_C7 and OsGrx_C2.1 Reduces Intracellular Arsenic Accumulation and Increases Tolerance in Arabidopsis thaliana

JOURNAL=Frontiers in Plant Science

VOLUME=7

YEAR=2016

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2016.00740

DOI=10.3389/fpls.2016.00740

ISSN=1664-462X

ABSTRACT=<p>Glutaredoxins (<italic>Grxs</italic>) are a family of small multifunctional proteins involved in various cellular functions, including redox regulation and protection under oxidative stress. Despite the high number of <italic>Grx</italic> genes in plant genomes (48 <italic>Grxs</italic> in rice), the biological functions and physiological roles of most of them remain unknown. Here, the functional characterization of the two arsenic-responsive rice Grx family proteins, OsGrx_C7 and OsGrx_C2.1 are reported. Over-expression of <italic>OsGrx_C7</italic> and <italic>OsGrx_C2.1</italic> in transgenic <italic>Arabidopsis thaliana</italic> conferred arsenic (As) tolerance as reflected by germination, root growth assay, and whole plant growth. Also, the transgenic expression of <italic>OsGrxs</italic> displayed significantly reduced As accumulation in <italic>A. thaliana</italic> seeds and shoot tissues compared to WT plants during both AsIII and AsV stress. Thus, <italic>OsGrx_C7</italic> and <italic>OsGrx_C2.1</italic> seem to be an important determinant of As-stress response in plants. <italic>OsGrx_C7</italic> and <italic>OsGrx_C2.1</italic> transgenic showed to maintain intracellular GSH pool and involved in lowering AsIII accumulation either by extrusion or reducing uptake by altering the transcript of <italic>A. thaliana AtNIPs</italic>. Overall, <italic>OsGrx_C7</italic> and <italic>OsGrx_C2.1</italic> may represent a Grx family protein involved in As stress response and may allow a better understanding of the As induced stress pathways and the design of strategies for the improvement of stress tolerance as well as decreased As content in crops.</p>