Integrated metabolomic and transcriptomic analyses provide insights into regulation mechanisms during bulbous stem development in the Chinese medicinal herb plant, Stephania kwangsiensis.

BACKGROUND: Stephania kwangsiensis Lo (Menispermaceae) is a well-known Chinese herbal medicine, and its bulbous stems are used medicinally. The storage stem of S. kwangsiensis originated from the hypocotyls. To date, there are no reports on the growth and development of S. kwangsiensis storage stems. RESULTS: The bulbous stem of S. kwangsiensis, the starch diameter was larger at the stable expanding stage (S3T) than at the unexpanded stage (S1T) or the rapidly expanding stage (S2T) at the three different time points. We used ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and Illumina sequencing to identify key genes involved in bulbous stem development. A large number of differentially accumulated metabolites (DAMs) and differentially expressed genes (DEGs) were identified. Based on the differential expression profiles of the metabolites, alkaloids, lipids, and phenolic acids were the top three differentially expressed classes. Compared with S2T, significant changes in plant signal transduction and isoquinoline alkaloid biosynthesis pathways occurred at both the transcriptional and metabolic levels in S1T. In S2T compared with S3T, several metabolites involved in tyrosine metabolism were decreased. Temporal analysis of S1T to S3T indicated the downregulation of phenylpropanoid biosynthesis, including lignin biosynthesis. The annotation of key pathways showed an up-down trend for genes and metabolites involved in isoquinoline alkaloid biosynthesis, whereas phenylpropanoid biosynthesis was not completely consistent. CONCLUSIONS: Downregulation of the phenylpropanoid biosynthesis pathway may be the result of carbon flow into alkaloid synthesis and storage of lipids and starch during the development of S. kwangsiensis bulbous stems. A decrease in the number of metabolites involved in tyrosine metabolism may also lead to a decrease in the upstream substrates of phenylpropane biosynthesis. Downregulation of lignin synthesis during phenylpropanoid biosynthesis may loosen restrictions on bulbous stem expansion. This study provides the first comprehensive analysis of the metabolome and transcriptome profiles of S. kwangsiensis bulbous stems. These data provide guidance for the cultivation, breeding, and harvesting of S. kwangsiensis.

Construction of a novel immune-related prognostic-predicting model of gastric cancer.

Gastric cancer (GC) is a common primary stomach tumor of the central nervous system with a poor prognosis. In this study, 274 differentially expressed immune-related genes (DEIRGs) were identified among six cell subpopulations in GSE112302 single-cell RNA sequencing (scRNA-seq) data of GC. Those DEIRGs were able to divide GC patients into three distinct subtypes with different overall survivals and tumor microenvironment. By univariate Cox and LASSO regression analyses, eight immune-related genes, including CTGF, CXCL3, CXCR4, NRP1, OAS1, SP1, STC1 and TAP1, were identified as GC prognostic signatures. Accordingly, a risk score model for predicting GC prognosis was constructed in TCGA-GC training cohort and validated in the external GSE66229 dataset. Moreover, a nomogram for predicting the survival of GC patients was also established based on independent prognostic factors (age, grade, cancer status and risk score) identified by univariate and multivariate Cox regression analyses. In addition, Gene Set Variation Analysis (GSVA) analysis indicated that the prognostic immune signatures may regulate GC via inflammation and cell proliferation related pathways, such as DNA replication, complement and coagulation cascades, focal adhesion and TGF-ß signaling pathway.

[Correlation of Agronomic Character of Panax notoginseng in Guangxi with Soil Physical and Chemical Properties].

Objective: To study the effect of physicochemical characteristics of soil on Panax notoginseng agronomic character, in order to offer the theory for selecting an appropriate soil to cultivate Panax notoginseng, and to build the production bases. Methods: To test and analyze Panax notoginseng agronomic character, to analyze the form of layered soil particles, p H value and soil fertility. At the same time, the analysis of Panax notoginseng plant height, leaf number, the length of taproot, the width of taproot, stem diameter, the width of residual part of stem, rootlet number, root fresh and dry weight and drying rate were carried out. Results: Panax notoginseng agronomic character had a large difference. The length of roots, the width of roots and a large number of rootlets had a promoting effect on accumulating biological yield. Nevertheless, the numbers of branches had no obvious impact on accumulating biological yield. Most of soil texture were silty clay or light clay of silty clay. Physical clay and coarse silt could promote the growth of Panax notoginseng. Sand grain had significant effect on Panax notoginseng growth. A reasonable use of nitrogenous fertilizer had a prominent promoting effect on the width of the medicine's root. In fact, the use of phosphorus potassium also had a great impact on Panax notoginseng growth. Conclusion: Panax notoginseng should be planted on the light clay which are loose and can irrigate and drain conveniently and contains many silty. The heavy clay soil which are defective aeration and contain cosmid has a bad influence of the growth of Panax notoginseng. It will cause a decrease of the yield of medicinal materials. Using nitrogenous fertilizer aptly also is an effective way to improve the quality and yield of Panax notoginseng.