The Functional Analysis Of A Rice WRKY Transcription Factor OsHsHS In Heat Stress Response

Heat stress is great harmful to rice,especially in the heading stage seriously affect rice fertility.Heat-shock response in plants is controlled by a complicated network,which has been widely studied.However,there are still many unknown nodes in the net.WRKY transcription factors belong to a superfamily which were mostly found in plants and are usually involved in the response to biotic and abiotic stress.We find a new WRKY factor,named OsHsHS(Orizaba sativa Hypersensitive to Heat Shock),and its function has not been reported.To reveal OsHsHS functions,we studied the expression patterns of OsHsHS gene using transgenic plant with OsHsHS-promoter-GUS and OsHsHS usually express in callus,leaves,stem section,ear,leaf sheath and germination seeds.The expressions in the leaves depended on the growth periods,and are much higher at heading stage than seedling stage.We discovered that its expression is the highest in callus and leaf sheath.We research the Transient expression assay of OsHsHS in tobacco leaves.The 35S:OsHsHS-GFP and the 35S:GFP vector were introduced into A.tumefacience strain G V3101.The cells were used to infiltrate six-week-old Nicotiana benthaminana leaves.The result shows that the OsHsHS fused with GFP protein in the nucleus while Contrast GFP spread throughout the cell,explaining OsHsHS localization in the nucleus.Therefore,the OsHsHS is characteristic of most WRKY proteins in common.The transcription of OsHsHS induced by high temperature stress.The OsHsHS-OX mutants is highly sensitive to change of temperature,even summer high temperature in Fuzhou will result in leaves wither and die.When we reduce the temperature,the process will slow or stop.Using RT-PCR method can further test the expression of heat-relate and disease-resistant related genes in OsHsHS-OX transgenic plants.ROF2 and OsHsfA2d,the two heat-related marker genes and OsPrla,OsOPR1,OsPR10,OsERF3,MPK3 related disease-resistant related genes in OsHsHS-OX mutant expression is significantly higher than the wild type.The over expression of transcription factor induces the accumulation of H2O2 and peroxidase.We have not found the protein responded with OsHsHS by using yeast two-hybrid analysis.According to the above analysis,it can be seen that the expression of OsHsHS is influenced by heat stress and it also can influence the expression of heat-relate and disease-resistant related genes.Relevant results make us have a deeper understanding to the function of OsHsHS,as well as it provide important scientific basis on reaction mechanism of plant disease resistance and art to clarify.