| With the deepening of the research, more and more function of DHHC-type zinc finger protein has been reported, which play an important role throughout the eukaryotes life. In the past, the study of DHHC proteins mainly concentrated in mammals, yeast and arabidopsis thaliana, but the research on OsDHHC protein in rice is very little and most of the function of the gene has not been reported. Therefore, we have analysed the DHHC-type zinc finger protein in rice through the method of bioinformatics and experiment and mainly studied the function of OsDHHC13. The main results obtained as follows:(1) Through bioinformatics analysis of the 30 OsDHHC gene in rice, we found the structure of OsDHHC is highly conservative. The protein sequence of 30 OsDHHC gene has six identical conservative amino acid residues and their DHHC-CRD domain are rich in Cys residue.Through the analysis of evolutionary tree we found that 30 OsDHHC gene family can be divided into a, b, x, s, t, c and d subfamily, and the number of introns and exons derived from one subfamily are the same and their have similar structure, and the same subfamily contain other highly similar domain besides the DHHC domain. At the same time,by gene chip we found that 26 OsDHHC gene were expressed in rice root, stem, leaf, flower and germ at a different level, showing these genes can play an role in every tissue during different periods.(2) We treated the rice seedlings with abiotic stress (salt, freezing, dehydration) to analyse the expression pattern of OsDHHC gene. The results showed that there are 12 OsDHHC genes down-or up-regulated in different extent, and the c subfamily are most sensitive to abiotic stress, suggesting that the 12 genes may be involved in regulation of abiotic stress response.(3)By analysing OsDHHC13 gene with bioinformatics, we found that OsDHHC13 protein is a membrane protein with four transmembrane, and the result analysis on its spatial structure showed that the protein had sulfur acyltransferase activity center, which suggestting that the protein has the function of the palm acylation. For promoter analysis, we found that the gene promoter sequences contain a variety of adversity light control?stress element and hormone response element, indicating that the protein may be involved in plant light signal transduction?hormone transduction and abiotic stress response.(4)We succeeded in constructing the 35S::OsDHHC13 recombinant plasmid and got 8 overexpression strain via agrobacterium to impregnate callus of rice. Through identification at DNA and RNA level and analysis of tissue expression pattern, we screened out 3 overexpression strains and found that the gene in seedling stage is mainly expressed in leaves and stems but also have some expression in roots. At reproductive stage the gene mainly expressed in leaf?root and leaf sheath.(5) Treating the wild type Kitaake rice respectively with NaCl, PEG4000, H2O2 and low temperature and analyzing expression level of OsDHHC13 gene, we found that the gene expression can be induced by Nacl?PEG andH2O2 indicating that the gene may be relative to salt stress?drought stress and oxidative stress.(6) In normal circumstances, the transgenic strains and wild type almost have no difference in the length of seedling roots, After treated with a certain concentration of H2O2 on rice seedling, we found that roots of overexpression strains was significantly longer than the wild type. Measuring the content of H2O2 in root, we found that the content of H2O2 in overexpression strains roots is significantly lower than the wild type.Quantitative analysis found that the expression levels of OsSOD1,OsCATB, OsAPX1 and OsAPX2 that related to ROS synthesis or clear increased significantly, These results indicate that under the condition of oxidative stress OsDHHC13 actually can promote expression of the genes that related to the removal of ROS, further regulating the dynamic balance of content of H2O2, and finally relieving the inhibition of H2O2 to root growth and development.The above results preliminarily prove that the genetic structure of OsDHHC is highly conservative in the evolutionary history of rice, They participate in the regulation of physiological functions in every periods of rice. The expression OsDHHC13 increased under the condition of oxidative stress and it can promote the expression of the genes that related to the removal of ROS, further regulating the dynamic balance of content of endogenous H2O2, and finally relieving the inhibition of H2O2 to root growth and development.lt is proved that OsDHHC13 genes involved in oxidative stress responses in rice... |
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