A CD6 homolog of Nile tilapia (Oreochromis niloticus) conserved binding bacteria involved in the regulation of Streptococcus agalactiae induced inflammation.

As a lymphocyte-specific surface receptor belonging to the cysteine-rich superfamily of scavenger receptors, CD6 acts as a pattern recognition receptor for microbial components and is involved in the regulation of inflammatory responses. However, the characteristics and functions of CD6 molecules in lower vertebrates represented by teleost fish are unknown. In this study, a CD6 homolog (designated OnCD6) was characterized from Nile tilapia (Oreochromis niloticus), and establishing its role as a PRRs that participates in immune recognition. OnCD6 contains an open reading frame of 1872 bp that encodes a peptide of 623 amino acids, and contains two conserved SR domain. Multiple sequence alignment revealed that OnCD6 shares a relatively high level of identity with those of other species. Transcriptional expression analysis revealed that OnCD6 was constitutively expressed in immunes tissues such as head kidney and thymus. The expression level of OnCD6 in mainly immune tissues were found significantly upregulated after the injection of Streptococcus agalactiae (S. agalactiae). Moreover, OnCD6 protein was located in the head kidney and brain, mainly over the plasma membrane of lymphocytes in these immune tissues. In vitro experiments showed that CD6 extracellular protein bound to and aggregated several Gram-positive and -negative bacterial strains through the recognition of bacterial surface conserved components LPS and LTA etc. In vivo experiments demonstrated that overexpression OnCD6 before S. agalactiae challenge significantly improved tilapia survival, and this was concomitant with reduced bacterial load and pro-inflammatory cytokines (IL-1ß and TNF-α). Taken together, our results illustrated the function of CD6 molecular pattern recognition receptors (PRRs) is conserved and plays an important role in antibacterial infection.

Purple Rehmannia: Investigation of the activation of R2R3-MYB transcription factors involved in anthocyanin biosynthesis.

Engineering anthocyanin biosynthesis in herbs could provide health-promoting foods for improving human health. Rehmannia glutinosa is a popular medicinal herb in Asia, and was a health food for the emperors of the Han Dynasty (59 B.C.). In this study, we revealed the differences in anthocyanin composition and content between three Rehmannia species. On the 250, 235 and 206 identified MYBs in the respective species, six could regulate anthocyanin biosynthesis by activating the ANTHOCYANIDIN SYNTHASE (ANS) gene expression. Permanent overexpression of the Rehmannia MYB genes in tobacco strongly promoted anthocyanin content and expression levels of NtANS and other genes. A red appearance of leaves and tuberous/roots was observed, and the total anthocyanin content and the cyanidin-3-O-glucoside content were significantly higher in the lines overexpressing RgMYB41, RgMYB42, and RgMYB43 from R. glutinosa, as well as RcMYB1 and RcMYB3 in R. chingii and RhMYB1 from R. henryi plants. Knocking out of RcMYB3 by CRISPR/Cas9 gene editing resulted in the discoloration of the R. chingii corolla lobes, and decreased the content of anthocyanin. R. glutinosa overexpressing RcMYB3 displayed a distinct purple color in the whole plants, and the antioxidant activity of the transgenic plants was significantly enhanced compared to WT. These results indicate that Rehmannia MYBs can be used to engineer anthocyanin biosynthesis in herbs to improve their additional value, such as increased antioxidant contents.

Characterization of CD166 from Nile tilapia (Oreochromis niloticus) displays a broad pathogen recognition spectrum and involved the immune response to microbial aggression.

CD166 is a member of the immunoglobulin superfamily of cell adhesion molecules, and its mediated adhesion plays a crucial role in different physiological and pathological phenomena, especially related to leukocyte extravasation, immune synapse stability, T cell activation and proliferation. In this study, CD166 was identified from Nile tilapia (Oreochromis niloticus, OnCD166). OnCD166 contains an open reading frame of 1671 bp that encodes a peptide of 556 amino acids, and contains five consecutive extracellular immunoglobulin domains. It's tissue distribution and expression patterns after S. agalactiae challenge were also investigated. OnCD166 is widely distributed in various tissues of healthy tilapia. After Streptococcus agalactiae challenge, OnCD166 expressions were significantly up-regulated in all tested immune tissues. Meanwhile, the recombinant OnCD166 (rOnCD166E) protein showed strong agglutinating activities against both Gram-negative bacteria and Gram-positive bacteria. Moreover, rOnCD166E could promote phagocytosis of macrophages. Taken together, our results illustrated that OnCD166 might as a receptor involved in the immune recognition and phagocytosis against invading pathogen, which play important roles in the immune responses of Nile tilapia against bacterial pathogens.

Peripherally inserted central catheters have a protective role and the effect of fluctuation curve feature in the risk of bloodstream infection compared with central venous catheters: a propensity-adjusted analysis.

BACKGROUND: The prevention of peripherally inserted central catheters (PICC)-associated BSI and central venous catheters (CVC)-associated BSI have been a topic of national importance in China. Therefore, we aimed to explore the epidemiological characteristics of central line-associated bloodstream infection (CLABSI), and to evaluate whether PICCs were associated with a protective effect for CLABSI. METHODS: A retrospective cohort study was conducted in teaching hospital in Western China. All adult patients received a CVC or PICC during their hospital stay were included from January 2017 to December 2020. Primary endpoint was CLABSI up to 30 days after CVC or PICC placement. Propensity scores with a 2:1 match was used to account for potential confounders, and restricted cubic spline was used to visualize the risk of CLABSI at different time points during the catheterization. RESULTS: A total of 224687 devices (180522 PICCs and 45965 CVCs) in 24879 patients were included. The overall incidence was 1.8 CLABSIs per 1000 catheter-days. The odds ratio (OR) value increased day by day after PICC insertion, reached a relatively high point on the 4th day, and decreased from days 5 through 8. From the 9th day of intubation the OR value began to gradually increase day by day again. After covariate adjustment using propensity scores, CVCs were associated with higher risk of CLABSI (adjHR = 3.27, 95% CI 2.38-4.49) compared with PICCs. CONCLUSIONS: PICCs have a protective role and the effect of fluctuation curve feature in CLABSI when compared to CVCs, and the first 8 calendar days after CVC insertion are the acute stage of CVC-associated BSI.

Workplace violence and the risk of post-traumatic stress disorder and burnout among nurses: A systematic review and meta-analysis.

AIM: This review examined the association between workplace violence and the risk of post-traumatic stress disorder (PTSD) and burnout among nurses. BACKGROUND: The extent to which workplace violence is associated with an increased risk of PTSD and burnout in nurses remains unclear. EVALUATION: We searched nine electronic databases (PubMed, Cochrane, Embase, Web of Science, CINAHL, PsycINFO, Chinese Biomedical, China National Knowledge Internet and WANFANG). KEY ISSUES: Overall, 114 full-text studies were identified; 43 met the inclusion criteria, of which 10 were included in the meta-analysis. Compared to their counterparts with non-exposure to workplace violence, nurses experiencing it had 2.13 and 2.25 times higher odds of reporting PTSD and burnout after adjusting the confounding factors. Additionally, the moderator and mediator factors might help reduce the risk of both in this population. CONCLUSION: This study indicated that workplace violence increases the risk of PTSD and burnout. IMPLICATIONS FOR NURSING MANAGEMENT: Our review identified the magnitude of the association between exposure to workplace violence and the reported symptoms of PTSD and burnout in nurses. Furthermore, multi-targeted efforts directed at the identified social/organizational, task-related and individual resources might help mitigate their harmful impact in the aforementioned population.

[Screening and identification of key enzyme genes for steroidal saponin biosynthesis in Dioscorea zingiberensis under low phosphorus stress].

To investigate the responses of key enzymes involved in steroidal saponin biosynthesis of Dioscorea zingiberensis to low phosphorus stress, we designed three treatments of severe phosphorus stress, moderate phosphorus stress, and normal phosphorus level. The D. zingiberensis plants were collected at the early, middle, and late stages of treatment. The content of total steroidal saponins in different tissues of D. zingiberensis was determined by spectrophotometry for the identification of the critical stage in response to low phosphorus stress. BGI 500 sequencing platform was employed to obtain the transcript information of D. zingiberensis samples at the critical stage of low phosphorus stress, and then a transcriptome library was constructed. The correlation between the expression of genes involved in steroidal saponin biosynthesis and the content of total steroidal saponins was analyzed for the screening of the key enzyme genes in response to low phosphorus stress. Further, the expression patterns of these genes were analyzed by real-time fluorescence PCR(qRT-PCR). The content of total steroidal saponins in D. zingiberensis had obvious tissue specificity under low phosphorus stress, and the early stage of stress was particularly important for D. zingiberensis to respond to low phosphorus stress. A total of 101 593 unigenes were obtained by transcriptome sequencing, of which 77.35% were annotated in NT, NR, SwissProt, KOG, GO, and KEGG. A total of 256 transcripts of known key enzyme genes in the biosynthetic pathway of steroidal saponins were identified. The expression levels of 69 transcripts encoding 18 catalytic enzymes were significantly correlated with the content of total steroidal saponins. The qRT-PCR results showed that several key enzyme genes presented different expression patterns in four tissues under low phosphorus stress. The results indicated that the content of total steroidal saponins and the expression of key enzyme genes regulating steroidal saponin biosynthesis in D. zingensis changed under low phosphorus stress. This study provides the biological information for elucidating the molecular mechanism of steroidal saponin biosynthesis in D. zingensis exposed to low phosphorus stress.

Conservation of structural and interactional features of CD226 and Necl5 molecules from Nile tilapia (Oreochromis niloticus).

CD226 interacts with its ligand Necl5 as a costimulatory signal. In this study, we cloned a CD226 from Nile tilapia (Oreochromis niloticus, named OnCD226) and a Necl5 (named OnNecl5). The open reading frame of OnCD226 was 1071 bp, encoding a protein of 356 amino acids. Sequence alignment analysis indicated that OnCD226 contained two Ig-like domains in ectodomain. The open reading frame of OnNecl5 was 1155 bp, encoding a protein of 384 amino acids, and there are three lg-like domains in the extracellular domain. In healthy tilapia, OnCD226 was distributed in all tested tissues and relatively higher in the brain, while OnNecl5 was relatively higher in the skin. After Streptococcus agalactiae infection, OnCD226 has the same up-regulated expression pattern as OnNecl5 in different tissues. After HKLs stimulation with S. agalactiae and Poly I:C, respectively. OnCD226 was significantly up-regulated (0.01 < p < 0.05) at 12 h and extremely significant up-regulation was observed (p < 0.01) at 48 h and 96 h, the peak was observed at 96 h after stimulation by S. agalactiae. After stimulation by Poly I:C, OnCD226 expression was extremely significant (p < 0.01) at 72 h and 96 h, the peak was observed at 96 h. After stimulation by Keyhole limpet hemocyanin (KLH), a classical T cell-dependent antigen, the expression of OnCD226 was significantly up-regulated in blood, head kidney, spleen, and thymus. Moreover, when compared with the first challenge, the gene expression of OnCD226 which response to the second challenge was up-regulated earlier. Subcellular co-localization studies showed that OnCD226 and OnNecl5 were distributed mainly in the cytomembrane. Yeast two-hybrid results, indicated a strong interaction between OnCD226 and OnNecl5. These results suggested that OnCD226 plays an important role during pathogens infection, and the interaction between CD226 and Necl5 is conserved in Nile tilapia.

Efficient CRISPR/Cas9-mediated genome editing in Rehmannia glutinosa.

KEY MESSAGE: Here, we cloned a phytoene desaturase (PDS) gene from Rehmannia glutinosa, and realized RgPDS1 knock out in R. glutinosa resulted in the generation of albino plants. Rehmannia glutinosa is a highly important traditional Chinese medicine (TCM) with specific pharmacology and economic value. R. glutinosa is a tetraploid plant, to date, no report has been published on gene editing of R. glutinosa. In this study, we combined the transcriptome database of R. glutinosa and the reported phytoene desaturase (PDS) gene sequences to obtain the PDS gene of R. glutinosa. Then, the PDS gene was used as a marker gene to verify the applicability and gene editing efficiency of the CRISPR/Cas9 system in R. glutinosa. The constructed CRISPR/Cas9 system was mediated by Agrobacterium to genetically transform into R. glutinosa, and successfully regenerated fully albino and chimeric albino plants. The next-generation sequencing (NGS) confirmed that the albino phenotype was indeed caused by RgPDS gene target site editing, and it was found that base deletion was more common than insertion or replacement. Our results revealed that zCas9 has a high editing efficiency on the R. glutinosa genome. This research lays a foundation for further use of gene editing technology to study the molecular functions of genes, create excellent germplasm, accelerate domestication, and improve the yield and quality of R. glutinosa.

Mindfulness, emotional intelligence and occupational burnout in intensive care nurses: A mediating effect model.

AIM(S): To construct structural equation models to test the mediating role of emotional intelligence in the relationship between mindfulness and occupational burnout. BACKGROUND: Reports assessing the relationships among mindfulness, emotional intelligence and burnout, specifically in ICU nurses, are scarce. METHODS: This was a descriptive, correlational, cross-sectional research design with 883 ICU nurses enrolled by convenience sampling from 29 ICUs in seven tertiary hospitals in urban areas of Chengdu, China. Mediation analysis was performed by structural equation modelling. Indirect effects were evaluated through bootstrapping. RESULTS: The associations among mindfulness, emotional intelligence, emotional exhaustion, depersonalization and personal accomplishment were all significant (p < .001). In the mediation models, emotional intelligence partially mediates the relationships between mindfulness and emotional exhaustion (indirect effect 0.118, p = .006; direct effect -0.374, p = .010; total effect -0.492, p = .011) and between mindfulness and depersonalization (indirect effect -0.182, p = .006; direct effect -0.452, p = .015; total effect -0.633, p = .018). Emotional intelligence plays a total mediating role between mindfulness and personal accomplishment (indirect effect 0.293, p = .004; direct effect 0.119, p = .053). CONCLUSIONS: The results suggest that nursing manager could implement mindfulness training to improve occupational burnout in ICU nurses. IMPLICATIONS FOR NURSING MANAGEMENT: Nursing managers could help create a more favourable working environment by providing mindfulness training. Such mindfulness training could help improve nursing quality, reduce errors and ensure patient safety, possibly improving patient prognosis and probably satisfaction.

MSCs attenuate hypoxia induced pulmonary hypertension by activating P53 and NF-kB signaling pathway through TNFα secretion.

Hypoxia could cause vascular smooth muscle hypertrophy, leading to high pulmonary circulation resistance, pulmonary artery (PA) pressure, even pulmonary arterial hypertension (PAH). Recent studies have demonstrated the ability of mesenchymal stem cell (MSC) to ameliorate PAH but the mechanism was controversial. In this study, we revealed that the growth rate of pulmonary artery smooth muscle cells (PASMCs) treated with hypoxia was significantly increased than normal and showed lower expression of potassium channels. However, cells co-cultured with MSC showed decreased proliferation capability and down-regulated expression of ion channel of PAMSCs. The protein array data showed that the changes of PAMSCs was substantially associated with a high level of tumor necrosis factor alpha (TNFα) secretion from MSC. We further demonstrated that TNFα rescued the cell behavior of PAMSCs through activating the expression of P53 and NF-kB and inducing cell cycle arrest by P21/CDK2/CDK4 downregulation. These findings suggested that MSCs could attenuate abnormal function of PAMSCs by TNFα secretion, which was more or less associated with the beneficial effects of MSC on improving PAH.

A Cascade Reaction of Michael Addition and Truce-Smiles Rearrangement to Synthesize Trisubstituted 4-Quinolone Derivatives.

A novel transition-metal-free cascade reaction to synthesize 4-quinolone derivatives has been demonstrated. Michael addition and Truce-Smiles rearrangement are included in this protocol, providing a broad scope of 4-quinolones in moderate-to-excellent yields. This work serves as an example of the use of sulfonamides through Truce-Smiles rearrangement to build heterocyclic compounds under mild conditions.

Metal-Free ß-Amino Alcohol Synthesis: A Two-step Smiles Rearrangement.

A novel method for the synthesis of ß-amino alcohols has been demonstrated under mild reaction conditions with a broad scope via a two-step Smiles rearrangement. What is more, theoretical calculations have been performed to confirm the rationality of the mechanism. The method has been proved to be notably effective for N-arylated amino alcohols, which are difficult to synthesize by traditional methods.

Molecular characterization and expression of CD48 in Nile tilapia (Oreochromis niloticus) in response to different stimulus.

CD48 is a glycosylphosphatidylinositol-anchored protein involved in lymphocyte adhesion, activation, and costimulation. In this study, the CD48 gene of tilapia (Oreochromis niloticus, named On-CD48), was cloned from the head kidney of tilapia. The coding sequences is 654 bp and encoding 217 amino acids. The deduced amino acid sequence of On-CD48 with an estimated molecular weight of 24.4 kDa and a theoretical pI of 5.03. Amino acid alignment indicated that it had two immunoglobulin-like domain conserved region. In healthy tilapia, the On-CD48 could be detected in all the examined tissues and the highest expression level in the spleen. The expression of On-CD48 in the spleen and head kidney was decreased after immunized by formalin-inactivated Streptococcus agalactiae, and the peak was observed in the spleen at 24 h and appeared again at 96 h, and in the head kidney gradual decline before 48 h then gradually increased to the original level. qPCR analysis of inactivated S. agalactiae, LPS and Poly I:C stimulated at the whole lymphocyte level showed that the stimulation of the Poly I:C was more sensitive. Prokaryotic expression results showed that efficient expression of On-CD48 protein could be realized after induced with 0.5 mmol L-1 IPTG in E. coli BL21 (DE3) for 10 h at 18 °C. The result of subcellular localization showed that On-CD48 were evenly distributed in the whole cell of HEK-293T. Western Blot confirmed that the molecular weight of the recombinant On-CD48 was about 21 kDa, consistent with the predicted result. The results of this study will lay a strong foundation for the further study of On-CD48 molecular function in tilapia.

Docosahexaenoic acid inhibits Ca2+ influx and downregulates CaSR by upregulating microRNA-16 in pulmonary artery smooth muscle cells.

Docosahexaenoic acid (DHA) is reported to have the potential to ameliorate pulmonary arterial hypertension (PAH), while the specific mechanism is still obscure. This study aims to investigate the function of DHA in pulmonary artery smooth muscle cells (PASMCs) and explore the underlying mechanism. In our study, DHA was used to incubate PASMCs. Cytosolic-free Ca2+ concentration ([Ca2+ ]cyt) was measured using Fluo-3 AM method. Real-time polymerase chain reaction was used to detect microRNA-16 (miR-16) and calcium-sensing receptor (CaSR) messenger RNA expression levels. CCK-8 assay, BrdU assay, and Transwell assay were employed to detect the effects of DHA on proliferation and migration of PASMCs. CaSR was confirmed as a direct target of miR-16 using dual-luciferase assay, polymerase chain reaction, and Western blot analysis. It was found that DHA significantly inhibited PASMC proliferation and migration and decreased [Ca2+ ]cyt. After transfection of miR-16 mimics, proliferation and migration ability of PASMCs were significantly inhibited, whereas opposite effects were observed after miR-16 inhibition. [Ca2+ ]cyt was also inhibited by miR-16 transfection. DHA then promoted the expression of miR-16, and the effects of DHA on PASMCs were annulled when miR-16 was inhibited. CaSR was identified as a direct target of miR-16. CaSR was inhibited directly by miR-16 and indirectly by DHA. In conclusion, DHA inhibits the proliferation and migration of PASMCs, and probably ameliorates PAH via regulating miR-16/CaSR axis.

Identification of a mitochondrial-targeting secretory protein from Nocardia seriolae which induces apoptosis in fathead minnow cells.

Nocardia seriolae is the main pathogen responsible for fish nocardiosis. A mitochondrial-targeting secretory protein (MTSP) 3141 with an N-terminal transit peptide (TP) from N. seriolae was predicted by bioinformatic analysis based on the genomic sequence of the N. seriolae strain ZJ0503. However, the function of the MTSP3141 and its homologs remains totally unknown. In this study, mass spectrometry analysis of the extracellular products from N. seriolae proved that MTSP3141 was a secretory protein, subcellular localization research showed the MTSP3141-GFP fusion protein co-localized with mitochondria in fathead minnow (FHM) cells, the TP played an important role in mitochondria targeting, and only the TP located at N-terminus but not C-terminus can lead to mitochondria directing. Moreover, quantitative assays of mitochondrial membrane potential (ΔΨm) value, caspase-3 activity and apoptosis-related gene (Bcl-2, Bax, Bad, Bid and p53) mRNA expression suggested that cell apoptosis was induced in FHM cells by the overexpression of both MTSP3141 and MTSP3141ΔTP (with the N-terminal TP deleted) proteins. Taken together, the results of this study indicated that the MTSP3141 of N. seriolae was a secretory protein, might target mitochondria, induce apoptosis in host cells and function as a virulence factor.

Prevalence and correlates of depression, anxiety and symptoms of stress in vocational college nursing students from Sichuan, China: a cross-sectional study.

Nursing students from vocational college programs contribute to over 60% of the nursing student population in China. However, there remains a lack of systematic, quantitative studies examining the prevalence of mental health problems in this population. The purpose of this study was to explore the prevalence of depression, anxiety and stress symptoms and associated factors in vocational college nursing students in Sichuan, China. A total of 554 nursing students from vocational colleges participated in this cross-sectional study. Outcomes were measured with the Depression, Anxiety and Stress Scale 21 (DASS 21). Logistic regressions analysis was performed to examine correlates of mental health problems. The prevalence rates of depression, anxiety and stress symptoms among vocational college nursing students in China were 28.7% (95% CI 24.9%-32.5%), 41.7% (95% CI 37.6%-45.9%) and 20.2% (95% CI 16.8%-23.6%). Mental health problems were elevated as compared to a reference population of Chinese college students of all majors. However, only two percent indicated to seek treatment. The most consistent correlates of mental health problems were reduced engagement in physical and other leisure activities, poor sleep quality, experience of negative life events and poor self-perceived mental health.

[Molecular cloning and expression analysis of iridoid synthase genes from Rehmannia glutinosa].

Iridoid synthase( IS),the key enzyme in the natural biosynthesis of vegetal iridoids,catalyzes the irreversible cyclization of 10-oxogeranial to epi-iridodial. In this study,we screened the Rehmannia glutinosa transcriptome data by BLASTn with Catharanthus roseus CrIS cDNA,and found four c DNA fragments with length of 1 527,1 743,1 425,1 718 bp,named RgIS1,RgIS2,RgIS3 and RgIS4,respectively. Bioinformatics analysis revealed that the four iridoid synthase genes encoding proteins with 389-392 amino acid residues,protein molecular weights were between 44. 30-44. 74 k Da,and theoretical isoelectric points were between 5. 30 and 5. 87. Subcellular localization predictions showed that the four iridoid synthase were distributed in the cytoplasm. Structure analysis revealed that R. glutinosa iridoid synthases contain six conserved short-chain dehydrogenase/reductase( SDR) motifs,and their 3 D models were composed typical dinucleotide-binding " Rossmann" folds covered by helical C-terminal extensions. Using the amino acid sequences of four R. glutinosa iridoid synthases,phylogenetic analysis was performed,the result indicated that RgIS3,CrIS and Olea europaea OeIS were grouped together,the other R. glutinosa iridoid synthases and fifteen proteins in other plants had close relationship. Real-time fluorescent quantitative PCR revealed that RgIS1 and RgIS3 highly expressed in unfold leaves,however,RgIS2 and RgIS4 highly expressed in stems and tuberous roots,respectively. RgIS3 showed higher expression levels in non-radial striations( nRS) of the two cultivars,and RgIS1 and RgIS2 had higher expression levels in nRS of QH,while RgIS4 had less expression levels in nRS of QH1. RgIS1,RgIS2 and RgIS3 were up-regulated by Me JA treatment,although the time and degree of response differed. Our findings are helpful to reveal molecular function of R. glutinosa iridoid synthases and provide a clue for studing the molecular mechanism of iridoid biosynthesis.

Cascade One-Pot Method To Synthesize Isoquinolin-1(2H)-ones with α-Bromo Ketones and Benzamides via Pd-catalyzed C-H Activation.

A cross-coupling strategy of palladium-catalyzed ortho-C-H bond activation and intramolecular addition of N-C annulation to synthesize isoquinolin-1(2H)-ones has been developed. A wide range of α-bromo ketones with different substituents proceeded smoothly in this reaction, and varieties of isoquinolin-1(2H)-one derivatives were obtained in moderate to good yields.

Molecular Regulation of Catalpol and Acteoside Accumulation in Radial Striation and non-Radial Striation of Rehmannia glutinosa Tuberous Root.

Rehmannia glutinosa L., a perennial plant of Scrophulariaceae, is one of the most commonly used herbs in traditional Chinese medicine (TCM) that have been widely cultivated in China. However, to date, the biosynthetic pathway of its two quality-control components, catalpol and acteoside, are only partially elucidated and the mechanism for their tissue-specific accumulation remains unknown. To facilitate the basic understanding of the key genes and transcriptional regulators involved in the biosynthesis of catalpol and acteoside, transcriptome sequencing of radial striation (RS) and non-radial striation (nRS) from four R. glutinosa cultivars was performed. A total of 715,158,202 (~107.27 Gb) high quality reads obtained using paired-end Illumina sequencing were de novo assembled into 150,405 transcripts. Functional annotation with multiple public databases identified 155 and 223 unigenes involved in catalpol and acteoside biosynthesis, together with 325 UGTs, and important transcription factor (TF) families. Comparative analysis of the transcriptomes identified 362 unigenes, found to be differentially expressed in all RS vs. nRS comparisons, with 143 upregulated unigenes, including those encoding enzymes of the catalpol and acteoside biosynthetic pathway, such as geranyl diphosphate synthase (RgGPPS), geraniol 8-hydroxylase (RgG10H), and phenylalanine ammonia-lyase (RgPAL). Other differentially expressed unigenes predicted to be related to catalpol and acteoside biosynthesis fall into UDP-dependent glycosyltransferases (UGTs), as well as transcription factors. In addition, 16 differentially expressed genes were selectively confirmed by real-time PCR. In conclusion, a large unigene dataset of R. glutinosa generated in the current study will serve as a resource for the identification of potential candidate genes for investigation of the tuberous root development and biosynthesis of active components.

[Progress on germplasm enhancement and breeding of Rehmannia glutinosa].

The history of Rehmannia glutinosa breeding has already beyond 100 years. There are rich cultivated varieties and wild germplasm resources in R. glutinosa. However, there also exist a lot of problems, such as, the pedigree of the existing varieties is not clear, the genetic basis is narrow, backward method of germplasm enhancement and breeding. Breeding of new varieties has been unable to meet the demand of R. glutinosa production in the new era. This paper summarizes the species of Rehmannia and their distribution, the diversity of plant morphology and the quality of R. glutinosa germplasm resources, as well as the progress of R. glutinosa breeding in recent 100 years. For ensuring the orderly, effective and safe production of R. glutinosa, the authors suggest to establish the wild resources protection area and germplasm resources garden, deeply study the genetic base of quality, strengthen application of new breeding method such as mutation breeding, haploid breeding and gene editing.