ABSTRACT
One new flavonoid, 5,7,8,4'-tetrahydroxy-3-methoxyflavone-8-O-ß-d-xylopyranoside (2), along with other four known flavones (1, 3-5) were isolated from the aerial parts of Solanum rostratum. 8-hydroxyflavonoid was isolated from series Androceras for the first time. The structure of the new compound 2 was determined on the basis of spectroscopic techniques, including IR, NMR and HRESI-MS. The chemotaxonomic significance of these compounds was summarised.
Subject(s)
Flavones/chemistry , Flavonoids/chemistry , Solanum/chemistry , Xylose/analogs & derivatives , Magnetic Resonance Spectroscopy , Molecular Structure , Solanum/classification , Spectrometry, Mass, Electrospray Ionization , Xylose/chemistryABSTRACT
5-Enolpyruvylshikimate-3-phosphate synthase (EPSPS), the target enzyme for glyphosate inhibition, catalyzes an essential step in the shikimate pathway for aromatic amino acid biosynthesis. The full-length cDNA of 1,751 nucleotides (CaEPSPS, Genbank accession number: EU698030) from Convolvulus arvensis was cloned and characterized. The CaEPSPS encodes a polypeptide of 520 amino acids with a calculated molecular weight of 55.5 kDa and an isoelectric point of 7.05. The results of homology analysis revealed that CaEPSPS showed highly homologous with EPSPS proteins from other plant species. Tissue expression pattern analysis indicated that CaEPSPS was constitutively expressed in stems, leaves and roots, with lower expression in roots. CaEPSPS expression level could increase significantly with glyphosate treatment, and reached its maximum at 24 h after glyphosate application. We fused CaEPSPS to the CaMV 35S promoter and introduced the chimeric gene into Arabidopsis. The resultant expression of CaEPSPS in transgenic Arabidopsis plants exhibited enhanced tolerance to glyphosate in comparison with control.
Subject(s)
3-Phosphoshikimate 1-Carboxyvinyltransferase/genetics , Cloning, Molecular , Convolvulus/genetics , Gene Expression Regulation, Plant , 3-Phosphoshikimate 1-Carboxyvinyltransferase/metabolism , Amino Acid Sequence , Base Sequence , Convolvulus/classification , Convolvulus/metabolism , DNA, Complementary/chemistry , DNA, Complementary/genetics , Drug Resistance/genetics , Enzyme Activation , Gene Expression Profiling , Glycine/analogs & derivatives , Glycine/pharmacology , Herbicides/pharmacology , Molecular Sequence Data , Phenotype , Phylogeny , Plants, Genetically Modified , Promoter Regions, Genetic , Sequence Alignment , GlyphosateABSTRACT
AIM: To investigate the possible effects of telmisartan and losartan on cardiac function in adriamycin (ADR)-induced heart failure in rats, and to explore the changes in plasma level of angiotensin-(1-7)[Ang-(1-7)] and myocardial expression of angiotensin II type 1/2 receptors (AT(1)R / AT(2)R) and Mas receptor caused by the two drugs. METHODS: Male Sprague-Dawley rats were randomly divided into 4 groups: the control group, ADR-treated heart failure group (ADR-HF), telmisartan plus ADR-treated group (Tel+ADR) and losartan plus ADR-treated group (Los+ADR). ADR was administrated (2.5 mg/kg, ip, 6 times in 2 weeks). The rats in the Tel+ADR and Los+ADR groups were treated orally with telmisartan (10 mg/kg daily po) and losartan (30 mg/kg daily), respectively, for 6 weeks. The plasma level of Ang-(1-7) was determined using ELISA. The mRNA and protein expression of myocardial Mas receptor, AT(1)R and AT(2)R were measured using RT-PCR and Western blotting, respectively. RESULTS: ADR significantly reduced the plasma level of Ang-(1-7) and the expression of myocardial Mas receptor and myocardial AT(2)R, while significantly increased the expression of myocardial AT(1)R. Treatment with telmisartan and losartan effectively increased the plasma level of Ang-(1-7) and suppressed myocardial AT(1)R expression, but did not influence the expression of Mas receptor and AT(2)R. CONCLUSION: The protective effects of telmisartan and losartan in ADR-induced heart failure may be partially due to regulation of circulating Ang-(1-7) and myocardial AT(1)R expression.
