[Bioinformatics analysis and expressed level of histone methyltransferase genes in Lonicera japonica].

Twenty-three histone methyltransferase genes were obtained from transcriptome dataset of Lonicera japonica. The nucleotide and proteins characteristics, subcellular localization, senior structural domains and conservative forecasting were analyzed. The result of phylogenetic tree showed that 23 histone methyltransferases were mainly divided into two groups: lysine methyltransferase and arginine methyltransferases. The result of gene expression showed that 23 histone methyltransferases showed preference in terms of interspecies and organs. They were more expressed in buds of L. japonica than in L. japonica var. chinensis and lower in leaves of L. japonica than in L. japonica var. chinensis. Eight genes were specific expressed in flower. These results provided basis for further understanding the function of histone methyltransferase and epigenetic regulation of active ingredients of L. japonica.

[Development of microsatellites and genetic diversity analysis of Scutellaria baicalensis Georgi using genomic-SSR markers].

A total of 12 775 SSRs were identified from Scutellaria baicalensis Georgi genomic database, accounting for 2.56% of the total genomic sequences. The result showed that S. baicalensis SSRs were based on 68.32% dinucleotide and 18.63% trinucleotide repeats; CT/GA and TTC/GAA were predominant in the dinucleotide motifs and the trinucleotide motifs respectively. Nine primers were selected to produce highly reproducible SSR bands and were used in studying the genetic diversity of S. baicalensis, 50 individuals from ten populations. 68 SSR polymorphic loci were detected, these loci were polymorphic and displayed 4 to 12 alleles per locus with a mean number of 7; the effect number of alleles was 3. Expected heterozygosities were 0.6 and were far more greater than the average in dicotyledonous plants. PIC (polymorphism information content) was 0.72, Shannon's information index was 1.32, these all proved that S. baicalensis had a high genetic diversity in general. Genetic differentiation among population Gst was 0.131, genetic variation among population accounted for 13.1% and genetic variation within population accounted for 86.9%. The cluster analysis showed that 10 populations S. Baicalensis were classified into 2 groups, but it was not associated with geographical distribution.

Overexpression of two R2R3-MYB genes from Scutellaria baicalensis induces phenylpropanoid accumulation and enhances oxidative stress resistance in transgenic tobacco.

MYB proteins are involved in many significant physiological and biochemical processes, including regulation of primary and secondary metabolism, flavonoid biosynthesis, response to various biotic and abiotic stresses, hormone synthesis and signal transduction. The functions of R2R3-MYB proteins in Scutellaria baicalensis Georgi under abiotic stress, however, has not been elucidated. To study the molecular mechanism by which MYB2 and MYB7 respond to abiotic stress in S. baicalensis, we analyzed the phenylpropanoid content, growth phenotype, antioxidant enzyme activity and flavonoid synthesis-associated gene expression in SbMYB2 or SbMYB7-overexpressing transgenic tobacco plants after treatment with NaCl, mannitol and abscisic acid (ABA). The transgenic tobacco showed a higher fresh weight than did the wild type (WT) tobacco. In contrast, antioxidant enzyme activity and flavonoid synthesis-related gene expression were markedly higher in WT tobacco after treatment with NaCl, mannitol and ABA, as compared to transgenic plants, This is likely because increased phenylpropanoid accumulation in transgenic tobacco plants played a central role in abiotic stress resistance. These results indicate that overexpression of SbMYB2 or SbMYB7 increased phenylpropanoid accumulation and enhanced NaCl, mannitol and ABA stresses tolerance in transgenic tobacco.

[Bioinformatics analysis of DNA demethylase genes in Lonicera japonica Thunb].

The DNA demethylase genes are widespread in plants. Four DNA demethylase genes (LJDME1, LJDME2, LJDME3 and LJDME4) were obtained from transcriptome dataset of Lonicera japonica Thunb by using bioinformatics methods and the proteins' physicochemical properties they encoded were predicted. The phylogenetic tree showed that the four DNA demethylase genes and Arabidopsis thaliana DME had a close relationship. The result of gene expression model showed that four DNA demethylase genes were different between species. The expression levels of LJDME1 and LJDME2 were even more higher in Lonicera japonica var. chinensis than those in L. japonica. LJDME] and LJDME2 maybe regulate the active compounds of L. japonica. This study aims to lay a foundation for further understanding of the function of DNA demethylase genes in L. japonica.

[Gene cloning and bioinformatics analysis of new gene for chlorogenic acid biosynthesis of Lonicera hypoglauca].

To obtain the key genes for chlorogenic acid biosynthesis of Lonicera hypoglauca, four new genes ware obtained from the our dataset of L. hypoglauca. And we also predicted the structure and function of LHPAL4, LHHCT1 , LHHCT2 and LHHCT3 proteins. The phylogenetic tree showed that LHPAL4 was closely related with LHPAL1, LHHCT1 was closely related with LHHCT3, LHHCT2 clustered into a single group. By Real-time PCR to detect the gene expressed level in different organs of L. hypoglauca, we found that the transcripted level of LHPAL4, LHHCT1 and LHHCT3 was the highest in defeat flowers, and the transcripted level of LHHCT2 was the highest in leaves. These result provided a basis to further analysis the mechanism of active ingredients in different organs, as well as the element for in vitro biosynthesis of active ingredients.

Transcriptome-wide analysis of SAMe superfamily to novelty phosphoethanolamine N-methyltransferase copy in Lonicera japonica.

The S-adenosyl-L-methionine-dependent methyltransferase superfamily plays important roles in plant development. The buds of Lonicera japonica are used as Chinese medical material and foods; chinese people began domesticating L. japonica thousands of years ago. Compared to the wild species, L. japonica var. chinensis, L. japonica gives a higher yield of buds, a fact closely related to positive selection over the long cultivation period of the species. Genome duplications, which are always detected in the domestic species, are the source of the multifaceted roles of the functional gene. In this paper, we investigated the evolution of the SAMe genes in L. japonica and L. japonica var. chinensis and further analyzed the roles of the duplicated genes among special groups. The SAMe protein sequences were subdivided into three clusters and several subgroups. The difference in transcriptional levels of the duplicated genes showed that seven SAMe genes could be related to the differences between the wild and the domesticated varieties. The sequence diversity of seven SAMe genes was also analyzed, and the results showed that different gene expression levels between the varieties could not be related to amino acid variation. The transcriptional level of duplicated PEAMT could be regulated through the SAM-SAH cycle.