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Abstract The tubers of Curcuma kwangsiensis are regarded as an important medicinal material in China. In C. kwangsiensis cultivation, tuber expansion is key to yield and quality, but the regulatory mechanisms are not well understood. In this study, metabolomic and transcriptomic analyses were conducted to elucidate the mechanism underlying tuber expansion development. The results showed that auxin (IAA), jasmonic acid (JA), gibberellin (GA3), ethylene (ETH), and brassinolide (BR) levels increased during tuber expansion development. Metabolomic analysis showed that 197 differentially accumulated metabolites (DAMs) accumulated during tuber expansion development and these also play important roles in the accumulation of carbohydrates and secondary metabolites. 6962 differentially expressed genes (DEGs) were enriched in plant hormone signal transduction, starch and sucrose metabolism, linoleic acid metabolism, MAPK signaling pathway as well as sesquiterpenoid and triterpenoid biosynthesis. Comprehensive analysis revealed that DEGs and DAMs of plant hormone signal transduction, ABC transporters and biosynthesis of phenylpropanoids and terpenoids are critical pathways in regulating tuber expansion. In addition, some transcription factors (ARF, C2H2, C3H, NAC, bHLH, GRAS and WRKY) as well as hub genes (HDS, HMGR, ARF7, PP2CA, PAL and CCOMT) are also involved in this process. This study lays a theoretical basis for the molecular mechanism of tuber expansion in C. kwangsiensis.

Objectives: To explore epidemiological changes of Japanese encephalitis (JE) in a long-time span and evaluate the impact of mass immunisation. Method: Data on JE cases from hospitals and the county Centers for Disease Control and Prevention in Guizhou Province was collected between 2005 and 2021. Epidemiological changes were analyzed according to a series of policy implementations and the coronavirus disease 2019 (COVID-19) pandemic. Results: A total of 5138 JE cases and 152 deaths were reported in Guizhou Province during 2005–2021. The average incidence and case fatality rates were 0.83/100,000 and 2.96%, respectively. The JE prevalence showed a declining trend over the years with the reduced incidence gap between age groups and narrowing of the high-epidemic regions. During the COVID-19 pandemic, the JE activity reached its nadir in 2020. The inclusion in the Expanded Program on Immunization of the JE vaccine and catch-up immunisations showed a significant impact on the JE declining incidence rate. Conclusions: The implementation of JE immunisation programs has played a crucial role in controlling its spread. Continued efforts should be made to maintain high coverage of the JE vaccine and strengthen disease surveillance systems, ensuring JE effective control and eventual elimination.

Abstract Background In Amomum tsaoko breeding, the low germination rate is the major limitation for their large-scale reproduction. We found that warm stratification was an effective treatment to break the seed dormancy of A. tsaoko prior to sowing and could be an important component of improving breeding programs. The mechanism of seed dormancy release during warm stratification remains unclear. Therefore, we studied the differences between transcripts and proteomes at 0, 30, 60, and 90 days of warm stratification, to identify some regulatory genes and functional proteins that may cause seed dormancy release in A. tsaoko and reveal their regulatory mechanism. Results RNA-seq was performed for the seed dormancy release process, and the number of differentially expressed genes (DEGs) was 3196 in three dormancy release periods. Using TMT-labelling quantitative proteome analysis, a total of 1414 proteins were defined as differentially expressed proteins (DEPs). Functional enrichment analyses revealed that the DEGs and DEPs were mainly involved in signal transduction pathways (MAPK signaling, hormone) and metabolism processes (cell wall, storage and energy reserves), suggesting that these differentially expressed genes and proteins are somehow involved in response to seed dormancy release process, including MAPK, PYR/PYL, PP2C, GID1, GH3, ARF, AUX/IAA, TPS, SPS, and SS. In addition, transcription factors ARF, bHLH, bZIP, MYB, SBP, and WRKY showed differential expression during the warm stratification stage, which may relate to dormancy release. Noteworthy, XTH, EXP, HSP and ASPG proteins may be involved in a complex network to regulate cell division and differentiation, chilling response and the seed germination status in A. tsaoko seed during warm stratification. Conclusion Our transcriptomic and proteomic analysis highlighted specific genes and proteins that warrant further study in fully grasping the precise molecular mechanisms that control the seed dormancy and germination of A. tsaoko. A hypothetical model of the genetic regulatory network provides a theoretical basis for overcoming the physiological dormancy in A. tsaoko in the future.

Gynostemma pentaphyllum an important medicinal herb, can absorb high amounts of cadmium (Cd) which can lead to excessive Cd contamination during the production of medicines and tea. Hence, it is crucial to investigate the response mechanism of G. pentaphyllum under Cd stress to develop varieties with low Cd accumulation and high tolerance. Physiological response analysis, transcriptomics and metabolomics were performed on G. pentaphyllum seedlings exposed to Cd stress. Herein, G. pentaphyllum seedlings could significantly enhance antioxidant enzyme activities (POD, CAT and APX), proline and polysaccharide content subject to Cd stress. Transcriptomics analysis identified the secondary metabolites, carbohydrate metabolism, amino acid metabolism, lipid metabolism, and signal transduction pathways associated with Cd stress, which mainly involved the XTH, EXP and GST genes. Metabolomics analysis identified 126 differentially expressed metabolites, including citric acid, flavonoid and amino acids metabolites, which were accumulated under Cd stress. Multi-omics integrative analysis unraveled that the phenylpropanoid biosynthesis, starch, and sucrose metabolism, alpha-linolenic acid metabolism, and ABC transporter were significantly enriched at the gene and metabolic levels in response to Cd stress in G. pentaphyllum. In conclusion, the genetic regulatory network sheds light on Cd response mechanisms in G. pentaphyllum.

Abstract Callerya speciosa (Champ. ex Benth.) Schot is a traditional Chinese medicine characterized by tuberous roots as the main organ of isoflavonoid accumulation. Root thickening and isoflavonoid accumulation are two major factors for yield and quality of C. speciosa. However, the underlying mechanisms of root thickening and isoflavonoid biosynthesis have not yet been elucidated. Here, integrated morphological, hormonal and transcriptomic analyses of C. speciosa tuberous roots at four different ages (6, 12, 18, 30 months after germination) were performed. The growth cycle of C. speciosa could be divided into three stages: initiation, rapid-thickening and stable-thickening stage, which cued by the activity of vascular cambia. Endogenous changes in phytohormones were associated with developmental changes during root thickening. Jasmonic acid might be linked to the initial development of tuberous roots. Abscisic acid seemed to be essential for tuber maturation, whereas IAA, cis-zeatin and gibberellin 3 were considered essential for rapid thickening of tuberous roots. A total of 4337 differentially expressed genes (DEGs) were identified during root thickening, including 15 DEGs participated in isoflavonoid biosynthesis, and 153 DEGs involved in starch/sucrose metabolism, hormonal signaling, transcriptional regulation and cell wall metabolism. A hypothetical model of genetic regulation associated with root thickening and isoflavonoid biosynthesis in C. speciosa is proposed, which will help in understanding the underlying mechanisms of tuberous root formation and isoflavonoid biosynthesis.