A Chloroplast-Localized Rubredoxin Family Protein Gene from Puccinellia tenuiflora (PutRUB) Increases NaCl and NaHCO(3) Tolerance by Decreasing H(2)O(2) Accumulation

Rubredoxin is one of the simplest iron–sulfur (Fe–S) proteins. It is found primarily in strict anaerobic bacteria and acts as a mediator of electron transfer participation in different biochemical reactions. The PutRUB gene encoding a chloroplast-localized rubredoxin family protein was screened from a yeast full-length cDNA library of Puccinellia tenuiflora under NaCl and NaHCO(3) stress. We found that PutRUB expression was induced by abiotic stresses such as NaCl, NaHCO(3), CuCl(2) and H(2)O(2). These findings suggested that PutRUB might be involved in plant responses to adversity. In order to study the function of this gene, we analyzed the phenotypic and physiological characteristics of PutRUB transgenic plants treated with NaCl and NaHCO(3). The results showed that PutRUB overexpression inhibited H(2)O(2) accumulation, and enhanced transgenic plant adaptability to NaCl and NaHCO(3) stresses. This indicated PutRUB might be involved in maintaining normal electron transfer to reduce reactive oxygen species (ROS) accumulation.