ABSTRACT
The rol genes on pRiA4 plasmid of Agrobacterium rhizogenes are potent genes that promote secondary metabolism. Molecular breeding of Atropa belladonna can be conducted by introducing rol genes to increase tropane alkaloids (TAs) content in A. belladonna. In this study, the rolB gene was overexpressed in A. belladonna plants to study the effect of rolB gene on the biosynthesis of TAs. The phenotype, TAs content and expression levels of key enzyme genes in the pathway of TAs biosynthesis of transgenic A. belladonna were analyzed. The results showed that transgenic A. belladonna had developed root system, enlarged leaves, increased leaf fresh weight, deepened leaf color, enlarged flowers, changed flower shape, reduced pistil height and decreased pollen vitality. The content of TAs in the stems of transgenic A. belladonna was significantly higher than that of the control, and the contents of scopolamine, anisodamine, hyoscyamine can reach 2.11-2.91, 1.23-2.37 and 4.88-5.20 times of the control, respectively. Compared with the control group, the expressions of key enzymes putrescine N-methyltransferase (PMT), type III polyketide synthase (PYKS), tropinone reductase I (TRI), aromatic amino acid aminotransferase 4 (ArAT4), UDP-glycosyltransferase 1 (UGT1) and hyoscyamine 6-β-hydroxylase (H6H) in the TAs biosynthesis pathway were up-regulated, and the expression of tropinone reductase II (TRII) as a metabolic shunting gene was down-regulated. The results indicated that rolB gene enhanced TAs synthesis ability in roots and accumulation in stems of A. belladonna by enhancing metabolic flow of TAs synthesis pathway and weakening the metabolic shunt of competing pathway. This study laid a foundation for molecular breeding of A. belladonna with high-yield TAs content using rolB gene.
ABSTRACT
On the basis of the Uncaria transcriptome, specific primers were designed for UrSTR. The full-length cDNA of UrSTR (GeneBank: OL310251) was 1 541 bp, encoding 345 amino acid residues, and the promoter region sequence of UrSTR (GeneBank: OL310252) was 1 179 bp. Phylogenetic tree is revealed that UrSTR had a closest relationship with STR from Ophiorrhiza pumila and Ophiorrhiza japonica. Localization of UrSTR protein is revealed located in the vacuole membrane. Plant-care analysis indicated that the promoter region sequence of UrSTR, covering multiple light, stress and hormone-response cis-regulatory elements, and verified transcriptional activity. The results of SDS-PAGE show that pET-28a-UrSTR recombinant protein was successfully expressed, and the size was anticipated. The UrSTR prokaryotic expression system needs to be optimized in the later stage. The research lays the foundation for further purification to study its structure and functional characterization of the UrSTR protein.
ABSTRACT
Hair roots induced by Agrobacterium rhizogene produce higher levels of secondary metabolites than non-induced plants, and the enhanced metabolic capacity is driven by the rol gene. We hypothesized that rol genes can be utilized to improve the biosynthesis of tropane alkaloids (TAs) in Atropa belladonna. In this study, the rolC gene from Agrobacterium rhizogene pRiA4 plasmid, driven by a CaMV35S promoter, was overexpressed in A. belladonna. The phenotypes, TAs content and transcriptional expression of key genes in TAs biosynthesis were analyzed in transgenic A. belladonna plants. Results show that transgenic A. belladonna exhibited a well-developed root system, male sterility, higher stamen column length than pistil, early flowering, internode shortening, smaller but more flowers, increased axillary buds and lateral buds, decreased apical dominance, and long and narrow leaves as compared to wild-type plants. Transgenic A. belladonna produced more TAs than wild-type plants, with the content of hyoscyamine, anisodamine and scopolamine reaching 2.58, 3.59 and 15.77-fold that of the control group, respectively. The gene expression of putrescine N-methyltransferase (PMT), tropinone reductase I (TRⅠ) and hyoscyamine 6-β-hydroxylase (H6H), key enzymes in TAs biosynthesis, were up-regulated compared with the control group. The above results indicate that the rolC gene enhances TAs biosynthesis in A. belladonna by up-regulating the expression of key enzymes in the TAs biosynthesis pathway, laying a foundation for genetic manipulation of A. belladonna to increase TAs content by increasing rolC gene expression.
ABSTRACT
OBJECTIVES@#To study the survival rate and the incidence of complications of very preterm infants and the factors influencing the survival rate and the incidence of complications.@*METHODS@#The medical data of the very preterm infants with a gestational age of <32 weeks and who were admitted to the Department of Neonatology in 11 hospitals of Jiangsu Province in China from January 2018 to December 2019 were retrospectively reviewed. Their survival rate and the incidence of serious complications were analyzed. A multivariate logistic regression analysis was used to evaluate the risk factors for death and serious complications in very preterm infants.@*RESULTS@#A total of 2 339 very preterm infants were enrolled, among whom 2 010 (85.93%) survived and 1 507 (64.43%) survived without serious complications. The groups with a gestational age of 22-25@*CONCLUSIONS@#The survival rate is closely associated with gestational age in very preterm infants. A low 1-minute Apgar score (≤3) may increase the risk of death in very preterm infants, while high gestational age, high birth weight, and prenatal use of glucocorticoids are associated with the reduced risk of death. A low 5-minute Apgar score (≤3) and maternal chorioamnionitis may increase the risk of serious complications in these infants, while high gestational age and high birth weight may reduce the risk of serious complications.
Subject(s)
Female , Humans , Infant, Newborn , Pregnancy , Gestational Age , Infant, Premature , Infant, Premature, Diseases , Infant, Very Low Birth Weight , Retrospective Studies , Survival RateABSTRACT
Objective@#To investigate the relationship of electromagnetic radiation (EMR) from 900 MHz cellphone frequency with testicular oxidative damage and its influence on the Prdx2 protein expression in the rat testis, and to explore the mechanism of Guilingji Capsules (GC) alleviating oxidative damage to the testis tissue.@*METHODS@#Fifty healthy SD male rats were randomly divided into five groups of equal number, sham-EMR, 4-h EMR, 8-h EMR, 4-h EMR+GC and 8-h EMR+GC and exposed to 900 MHz EMR (370 μW/cm2) for 0, 4 or 8 hours daily for 15 successive days. The rats of the latter two groups were treated intragastrically with GC suspension and those of the first three groups with pure water after exposure to EMR each day. After 15 days of exposure and treatment, all the rats were sacrificed and their testis tissue collected for observation of the histomorphological and ultrastructural changes by HE staining and transmission electron microscopy, measurement of the levels of serum glutathione (GSH), superoxide dismutase (SOD) and malondialdehyde (MDA) with thiobarbiuric acid and determination of the Prdx2 protein expression by immunohistochemistry and Western blot.@*RESULTS@#Compared with the rats in the sham-EMR group, those in the 4-h and 8-h EMR groups showed different degrees of histomorphological and ultrastructural changes in the testis tissue, significantly decreased levels of GSH (［80.62 ± 10.99］ vs ［69.58 ± 4.18］ and ［66.17 ± 8.45］ mg/L, P < 0.05) and SOD (［172.29 ± 10.98］ vs ［158.92 ± 6.46］ and ［148.91 ± 8.60］ U/ml, P < 0.05) and increased level of MDA (［7.51 ± 1.73］ vs ［9.84 ± 1.03］ and ［11.22 ± 2.13］ umol/ml, P < 0.05), even more significantly in the 8-h than in the 4-h EMR group (P < 0.05). In comparison with the sham-EMR group, the expression of the Prdx2 protein was markedly downregulated in the 4-h and 8-h EMR groups (0.56 ± 0.03 vs 0.49 ± 0.03, 0.21 ± 0.01, P < 0.05), but again upregulated in the 4-h and 8-h EMR+GC groups (0.55±0.03 and 0.37±0.04) (P < 0.05).@*CONCLUSIONS@#Electromagnetic radiation from cellphones can cause ultrastructural damage to the testis tissue of male rats, while Guilingji Capsules can alleviate it, presumably by upregulating the Prdx2 protein expression in the testis tissue and reducing testicular oxidative damage.