Polygonatum sibiricum polysaccharides (PSPs) are used to improve immunity, alleviate dryness, promote the secretion of fluids, and quench thirst. However, the PSP biosynthetic pathway is largely unknown. Understanding the genetic background will help delineate that pathway at the molecular level so that researchers can develop better conservation strategies. After comparing the PSP contents among several different P. sibiricum germplasms, we selected two groups with the largest contrasts in contents and subjected them to HiSeq2500 transcriptome sequencing to identify the candidate genes involved in PSP biosynthesis. In all, 20 kinds of enzyme-encoding genes were related to PSP biosynthesis. The polysaccharide content was positively correlated with the expression patterns of β-fructofuranosidase (sacA), fructokinase (scrK), UDP-glucose 4-epimerase (GALE), Mannose-1-phosphate guanylyltransferase (GMPP), and UDP-glucose 6-dehydrogenase (UGDH), but negatively correlated with the expression of Hexokinase (HK). Through qRT-PCR validation and comprehensive analysis, we determined that sacA, HK, and GMPP are key genes for enzymes within the PSP metabolic pathway in P. sibiricum. Our results provide a public transcriptome dataset for this species and an outline of pathways for the production of polysaccharides in medicinal plants. They also present more information about the PSP biosynthesis pathway at the molecular level in P. sibiricum and lay the foundation for subsequent research of gene functions.

Rosemary (Rosmarinus officinalis) is a perennial herb with fragrant endemic to Mediterranean region. Despite its important economic values on flavour, food and medicinal industry, the whole chloroplast (cp) genome of it has not been reported yet. Here, the complete chloroplast genome of the R.officinalis has been reconstructed from the whole-genome Illumina sequencing data. The circular genome is 152,462 bp in size, and comprises a pair of inverted repeat (IR) regions of 25,569 bp each, a large single-copy (LSC) region of 83,355 bp and a small single-copy (SSC) region of 17,969 bp. The overall GC content of the cp genome was 38.0%. The chloroplast genome contains 132 genes, including 94 protein-coding genes, 30 transfer RNA genes, and eight ribosomal RNA genes. Phylogenomic analysis strongly supported the close relationship of R. officinalis and Scutellaria baicalensis.