Alternative Splicing Analysis Of Chinese Fir And Preliminary Study On Autotoxicity Stress

Alternative splicing refers to the formation of various splicing isoforms by different pertutation and combination of the exons and introns of precursor mRNA,which is an important post-transcriptional regulation and leads to diversity of transcripts and protein.In this study,the common xylem,phloem,root and leaf tissues were used as material and combined with the third generation single molecule sequencing technique.In total,137,606 full-length transcript sequences were obtained and clustered into 27,670 Unigenes and.These Unigenes have a high reference value with superior contiguity because these reference sequences were generated without transcriptome assembly.Using bioinformatics algorithm,3,260 gene loci with alternative splicing events were identified,and the length of the intron retention region was much higher than that of other alternative splice types.It is interesting that splicing factors itself is also subjected to the regulation of alternative splicing.In order to validate above result,DSN-based genomic library was constructed and 172,594,427 double-ended sequencing fragments were obtained using second generation sequencing.After assembly,the above sequence was mapped to the contig sequences and verify the results of PacBio sequencing.The transcriptome of xylem,phloem,roots and leaves of Chinese fir was constructed due to the advantage of second-generation sequencing on the higher sequencing depth.Combined with the second generation high-throughput sequencing,the differential expression of different tissue genes were analyzed,and 2,536 differences expression Unigenes were identified.The autotoxicity stress of Chinese fir cultured in 1/2 MS medium was investigated.The phonotype was concentration dependent in response to the stress of salicylic acid.At present,we are collecting the xylem material to identify differential alternative splicing site.The preliminary results of this paper will lay a solid foundation for the further study on post-transcriptional regulation of Chinese fir under autotoxicity.