ABSTRACT
Objective: To obtain the functional genes in Arctium lappa and analyze the key enzyme genes involved in biosynthesis pathway of lignin. Methods: The transcriptome dataset of roots of A. lappa was obtained by using the BGISEQ-500 sequencing platform. Unigenes were de novo assembled and annotated according to the existing nucleic acids and protein databases. The key enzyme genes involved in lignin biosynthesis pathway were analyzed and the three-dimensional model of phenylalanine ammonialyase (AlPAL) was generated by the SWISS-MODEL and PyMol. Results: A total of 54 215 Unigenes were obtained by de novo assembly, and 42 003 Unigenes were annotated in at least one public database. A total of 1 668 Unigenes were identified to be plant transcription factors (TFs), which belong to 54 TF families, and 423 Unigenes were found to be involved in the biosynthesis pathway of lignin. Structure model indicated that AlPAL was a homotypic tetramer, and each monomer was consisted of three domains, including 4-methyl-imidazole-5-ketone (MIO) domain, core domain and shield domain. The MIO domain contained three conserved amino acids (ASG), which formed the catalytic activity center of the enzyme. Conclusion: This study was the first de novo transcriptome assembly of A. lappa, which will lay the foundation for the identification of functional genes, secondary metabolic pathway and the study of regulation mechanism of biosynthesis pathway of lignin in A. lappa in the future.
ABSTRACT
Objective To obtain the transcriptome dataset of roots of Dictamnus dasycarpus. Methods The root transcriptome dataset of D. dasycarpus was obtained using the high-throughput sequencing platform Illumina HiSeqTM 2000 150PE, followed by systemic bioinformatics analyses. Results A great number of 69 643 286 high quality clean reads were obtained by the transcriptome sequencing analyses. Using Trinity de novo assembling, a total of 49 050 unigenes were finally obtained, with an average length of 841 nt. BLAST analysis indicated that 31 636 (accounting 64.49% of the total unigenes), 22 367 (45.60%), 19 246 (39.23%), 12 595 (25.68%) unigenes were successfully annotated in the NR, Swiss-port, KOG, and KEGG databases, respectively. And GO classification contained the basic three major groups, including biological process, cellular component, and molecular function with 42 subgroups. A total of 132 KEGG standard metabolic pathways were designated, 18 of which were defied as the secondary metabolism. Further analysis revealed that a total of 90 unigenes were involved in the biosynthesis of various alkaloids. Of all unigenes, 1 908 were predicted to have CDS, and 55 families of plant transcription factors were also identified. Using MISA prediction, 4 579 simple sequence repeats (SSRs) were obtained, among which the tri-nucleotide SSRs were abundant with 2 021 (44.1%), whereas the penta-nucleotide SSRs accounted for 3.5%. Conclusion The root transcriptome of D. dasycarpus revealed by the high-throughput sequencing technology will be important for gene functional characterization, secondary metabolism pathway exploration, and regulation mechanism research in this species.