The Zinc Finger Protein OsZFP6 Expression Features And Functions In Saline-alkali Stress Response

Soil alkalization severely affects crop growth and agricultural productivity.Alkali salts impose ionic,osmotic,and high pH stresses on plants.Plants have been able to protect themselves by generating the corresponding reaction pathways via recognizing external signals which could be transduced to the interior of cells through signal transduction and from environmental stress.The role of zinc finger proteins on stress conditions has been widely reported,however,little is known concerning the function of C2HC type zinc finger proteins responsing to alkali stress in rice.In this study,based on the expression sequence tags screened from previous work,BLAST analysis showed that the gene encoded 304 amino acids with molecular weight 33.6kDa which was similar to the coding gene(Accession number:AK068488).Besides,the protein structure anlasysis reveals the gene encoded C2HC zinc finger protein,indicating that it belongs to the family of Zinc Finger and we named it OsZFP6.The gene was cloned from rice variety Nipponbare by RT-PCR.Southern blot and expression of various tissues analysis showed that the gene appeared as a single copy in rice genome and expressed in root,stem,leave,leave sheath and panicle in reproductive stage.Meanwhile,the expression level of OsZFP6 was increased by abiotic stress,including alkali(NaHCO3)and H2O2 treatment in two-week old rice leaves but decreased in roots.Thus,it was speculated that OsZFP6 was involved in the regulation corresponding reaction pathways of resistance.We fused a green fluorescent protein(GFP)and the GFP signals were found in the nucleus suggesting that OsZFP6 plays an important role in the nucleus.Moreover,Arabidopsis overexpressed OsZFP6 were more tolerant to both NaHCO3 and H2O2 treatments.What's more,the overexpressed plants were higher than WT in plant height and fresh weight,but the contents of MDA and H2O2 in vivo were lower than non-transgenic plants.The expression level of AtSOD1,AtAPX3,AtCAT1 and AtSOS1 increased significantly in overexpressing plants after stress treatment.Additionally,overexpressing OsZFP6 rice was more tolerant to NaHCO3 than WT at post-germination stage.In addition,the physiological index and growth of OsZFP6 overexpressed rice is better than that of wild plants.Preliminarily,it was speculated that OsZFP6 gene participated in the regulation of resistance and it maybe play a vital role in transcription regulation.Overall,we uncovered a role for OsZFP6 in NaHCO3 stress responses and identified OsZFP6 as a putatively useful gene for developing crops with increased alkali tolerance.