Wheat Histone Gene Expression And Its Salt Tolerance

Salt stress induces stoma-closing, photosynthesis-decreasing,over energy-consuming and unbalance of inorganic ion absorbing and damages the functions of plasma membrane.Now many salt-inducible genes and upstream sequences have been cloned, and there was certainly progress on Molecular mechanism of plant biotic and abiotic stress signaling. Some salt-inducible genes have been transformed into plants, and it was evidenced that exogenous gene can enforce the ability to tolerate salt stress.The nucleosome consists of an octamer of two copies of the four core histones H2A, H2B, H3 and H4 in eukaryotes;many histone post-translational modifications can serve a distinct function in transcriptonal regulation (e.g.methylation,acetylation,phosp-horylation),and that indicated they could play a key role on the molecular mechanisms of salt-stress tolerance. RH3.2A was cloned through RT-PCR from salt-treated rice seedlings by Qiu Sheng Ping.The mRNA expression analysis of RH3.2A revealed that RH3.2A gene was upregulated by salt stress in rice roots and ABA treatment in seedlings. The potential role of RH3.2A during salt stress was discussed.For investigating the Shan Rong 3 wheat (salt-tolerant wheat) transcriptional profiling salt stress,RNA samples were collected at different hours mixly influence dye-labeled complimentary DNA were used to hybridize with the whole genome wheat gene chip. Data analysis indicated that most of the histone genes was down-regulated simultaneously but interestingly,there were great changes of different expressed histone genes,even individual histone genes were up-regulated. In Jinan 177,22 histone genes were upregulated by salt stress in leaves and 9 histone genes were downregulated by salt stress in leaves; 9 histone genes were upregulated by salt stress in roots and 124 histone genes were downregulated by salt stress in roots.In Shan rong 3,5 histone genes were upregulated by salt stress in leaves and 122 histone genes were downregulated by salt stress in leaves; 37 histone genes were upregulated by salt stress in roots and 20 histone genes were downregulated by salt stress in roots. This were further verified to be true by Real Time PCR. Generally speaking,Real Time PCR analysis indicated that five cloned histone genes expressed the same as gene chip's data.At last we have chosen one of them named I-H2B to Transform of Arabidopsis.Now,we have TO seeds for investigating its function in plant.