Transcriptome Analysis Of Metasequoia Glyptostroboides Different Organs And Screening And Comparing Of Genes Response To Water

Plants have a complex signaling network to adapt to drought stress and flooding stress caused by adverse water conditions.A series of important genes are involved in stress sensing,signal transduction and downstream physiological and morphological changes.These genes have been identified and studied in model species or crops.However,similar research is very few in woody plants.Rare relict plant Metasequoia glyptostroboides was selected as study object in our research.Transcriptome data of multiple tissues from one M.glyptostroboides mature tree and root,stem,and leaf of its seedlings were generated and the data were used to construct the water response signal pathways of M.glyptostroboides.Then the differential expression of key functional genes and regulatory genes in root,stem,and leaf of seedlings were screened and compared,and the response models of different organs were discussed,which laid a foundation for the study of adaptive evolution of M.glyptostroboides.Main results are as follows:1)After transcriptome sequencing of several tissues of M.glyptostroboides,134.54 GB data were obtained,and 152754 Unigenes were spliced,among which110332 Unigenes were annotated.A relatively complete gene resource library of M.glyptostroboides was established.2)The molecular signaling pathways in response to drought stress and flooding stress were established and 532 genes of M.glyptostroboides involved in these pathways were identified.Among the 532 genes,45 participate in flooding stress,including 8 ERF-VII transcription factors;40 single-copy genes as well as 9 protein gene families(466 members),and 6 transcription factor families take part in drought response pathway.These genes provided useful information for M.glyptostroboides in studing response to flooding and drought stress.3)The transcriptome comparison of different vegetative organs showed that the gene expression related to ethylene synthesis,ethylene response factor,abscisic acid synthesis and signal transduction,anaerobic metabolism in root were higher than those in stem and leaf,while the expression of proline synthesis genes in root,stem and leaf had no significant difference.In addition,the expression level of genes in antioxidant enzyme system in leaf was higher than that in root and stem.The amount of gene expression in stem were between root and leaf.These results indicated that root is the main organ in response to drought and flooding stress in M.glyptostroboides.