Transcriptome Analysis on Leaf of Ligustrum Quihoui Carr.

OBJECTIVE To explore the genetic basis of the biosynthesis of the ingredients in Ligustrum quihoui Carr.. METHODS The high throughout sequencing was used to sequence the transcriptome in leaf of Ligustrum quihoui Carr.. by Illumina/Solexa Hiseq 2000. Gene function annotation and SSR site search were carried out in combination with bioinformatics methods. RESULTS The total of 4 907 020 800 clean reads was obtained including 4.90 Gb valid data. Based on the bioinformatics analysis, 157 450 Unigenes were received with the total read length of 115.49 Mb, the average read length of 734 bp and N₅₀ of 1 510 bp. Further functional classification indicate that 17 756 Unigenes were classified into cellular components, molecular functions and biological processes in GO database. Aligning Unigenes with COG database, 25 functional categories could be obtained, among which lots of Unigenes involved in nutritional function of leaf to synthesize and transport substances. As the search object, Unigene could be located into 21 kinds of metabolic pathways in KEGG database, in which the number of Unigene involved in the production of important secondary phenylpropanoid, metabolites flavonoids and terpenoids was 860, 216 and 806. The 17 593 SSRs were found by SSR analysis software and the highest frequency was di-nucleotide repents. CONCLUSION This study is the first comprehensive study on transcriptome of Ligustrum quihoui Carr.. The key genes involved in secondary metabolism can lay the foundation for studying the mechanism of biosynthesis and regulation of medicinal components of Ligustrum quihoui Carr..