Elicitor-activated phospholipase A(2) generates lysophosphatidylcholines that mobilize the vacuolar H(+) pool for pH signaling via the activation of Na(+)-dependent proton fluxes. (1/21)

The elicitation of phytoalexin biosynthesis in cultured cells of California poppy involves a shift of cytoplasmic pH via the transient efflux of vacuolar protons. Intracellular effectors of vacuolar proton transport were identified by a novel in situ approach based on the selective permeabilization of the plasma membrane for molecules of < or = 10 kD. Subsequent fluorescence imaging of the vacuolar pH correctly reported experimental changes of activity of the tonoplast proton transporters. Lysophosphatidylcholine (LPC) caused a transient increase of the vacuolar pH by increasing the Na(+) sensitivity of a Na(+)-dependent proton efflux that was inhibited by amiloride. In intact cells, yeast elicitor activated phospholipase A(2), as demonstrated by the formation of LPC from fluorescent substrate analogs, and caused a transient increase of endogenous LPC, as determined by matrix-assisted laser desorption and ionization time-of-flight mass spectrometry. It is suggested that LPC generated by phospholipase A(2) at the plasma membrane transduces the elicitor-triggered signal into the activation of a tonoplast H(+)/Na(+) antiporter.  (+info)

Quaternary benzo[c]phenanthridine alkaloids as inhibitors of dipeptidyl peptidase IV-like activity baring enzymes in human blood plasma and glioma cell lines. (2/21)

Quaternary benzo[c]phenanthridine alkaloids (QBA), fagaronine (FA), sanguinarine (SA), chelerythrine (CHE) and the QBA extract from Macleya cordata (EX) exerted differential inhibitory effect on the hydrolytic activity of particular dipeptidyl peptidase (DPP)-like enzyme isolated from human blood plasma and from human and rat glioma cell lines. The low-MW form of DPP-IV-like enzyme activity, corresponding most probably to DPP-8, observed only in glioma cells but not in human plasma, was inhibited preferentially by SA, CHE and EX, and only slightly by FA. The alkaloid inhibitory effect was concentration-dependent in the range 25-150 mM and directly pH-related. In addition, a subtle but consistent inhibition of the intermediate-MW form of DPP-IV-like enzyme activity, ascribed to DPP-IV/CD26, observed only in human plasma and of the attractin (high-MW form of DPP-IV-like enzyme activity, expressed in U87 glioma cells) by the studied alkaloids was observed. We conclude that some of the QBA biological effects could be determined by tissue and cell type specific dipeptidyl peptidase IV-like molecules expression pattern.  (+info)

Macleya cordata and Prunella vulgaris in oral hygiene products - their efficacy in the control of gingivitis. (3/21)

A double-blind, placebo-controlled clinical trial was performed to investigate the effectiveness of a herbal-based dentifrice in the control of gingivitis. Forty volunteers completed the 84-day study. All subjects were balanced for parameters measured - plaque index (PI), community periodontal index of treatment needs (CPITN) and papillary bleeding index (PBI). The dentifrice was effective in reducing symptoms of gingivitis as evaluated by the CPITN and PBI indexes.  (+info)

Phylogenetics of Papaver and related genera based on DNA sequences from ITS nuclear ribosomal DNA and plastid trnL intron and trnL-F intergenic spacers. (4/21)

BACKGROUND AND AIMS: Representatives from Papaver, Roemeria, Stylomecon and Meconopsis were studied to elucidate phylogenetic relationships between Papaver and these closely allied genera. METHODS: Two molecular data sets were used individually and combined and included sequences from the internally transcribed spacer region (ITS) of 18S-26S nuclear ribosomal DNA and the trnL intron and the trnL-trnF intergenic spacer region of plastid DNA. KEY RESULTS: Parsimony analysis demonstrated that the genus is not monophyletic unless the closely related Roemeria, Stylomecon and Meconopsis cambrica are included in a revised circumscription of Papaver. Three distinct clades are resolved in a combined ITS and trnL-F analysis. Clade 1 consists of Papaver sect. Meconella and Asian Meconopsis. Clade 2 contains a group here identified as Papaver s.s., comprising sections Carinatae, Meconidium, Oxytona, Papaver, Pilosa, Pseudopilosa and Rhoeadium. Clade 3 consists of Papaver sect. Argemonidium and Roemeria refracta. A number of diagnostic indels support these groupings. Within clade 2, sects. Papaver and Rhoeadium are either not monophyletic or lack evidence supporting their monophyly. CONCLUSIONS: The results of this molecular analysis indicate that a number of morphological characters such as valvate capsule dehiscence, dark or light filaments and sessile stigmatic discs have arisen in parallel. The phylogenetic trees are incongruent with the existing taxonomy of Papaver, and a revised classification is suggested.  (+info)

Diversity and evolution of CYCLOIDEA-like TCP genes in relation to flower development in Papaveraceae. (5/21)

Monosymmetry evolved several times independently during flower evolution. In snapdragon (Antirrhinum majus), a key gene for monosymmetry is CYCLOIDEA (CYC), which belongs to the class II TCP gene family encoding transcriptional activators. We address the questions of the evolutionary history of this gene family and of possible recruitment of genes homologous to CYC in floral development and symmetry in the Papaveraceae. Two to three members of the class II TCP family were found in each species analyzed, two of which were CYC-like genes, on the basis of the presence of both the TCP and R conserved domains. The duplication that gave rise to these two paralogous lineages (named PAPACYL1 and PAPACYL2) probably predates the divergence of the two main clades within the Papaveraceae. Phylogenetic relationships among angiosperm class II TCP genes indicated that (1) PAPACYL genes were closest to Arabidopsis (Arabidopsis thaliana) AtTCP18, and a duplication at the base of the core eudicot would have given rise to two supplementary CYC-like lineages; and (2) at least three class II TCP genes were present in the ancestor of monocots and eudicots. Semiquantitative reverse transcription-polymerase chain reaction and in situ hybridization approaches in three species with different floral symmetry indicated that both PAPACYL paralogs were expressed during floral development. A pattern common to all three species was observed at organ junctions in inflorescences and flowers. Expression in the outer petals was specifically observed in the two species with nonactinomorphic flowers. Hypotheses concerning the ancestral pattern of expression and function of CYC-like genes and their possible role in floral development of Papaveraceae species leading to bisymmetric buds are discussed.  (+info)

Hexoses as phloem transport sugars: the end of a dogma? (6/21)

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Macleaya cordata extract and Sangrovit genotoxicity. Assessment in vivo. (7/21)

BACKGROUND: Sanguinarine (SG) has been reported to form DNA adducts in vitro and increase the levels of DNA single strand breaks in the blood and bone marrow of mice treated intraperitoneally with SG. Recently, we showed no genotoxic effects of orally administrated 120 mg/kg feed Macleaya cordata extract (a mixture of sanguinarine and chelerythrine) in pigs or rats in 90-day studies. The goal of this paper was to assess the possible genotoxicity of M. cordata extract when included as a dietary admixture to rodents at concentrations providing 600 mg/kg feed and 100, 7000 or 14000 mg/kg feed Sangrovit (natural feed additive containing M. cordata extract and powdered M. cordata) in a 90-day pilot study. METHODS AND RESULTS: The rats consumed ad libitum either the standard diet or the diets containing 367 ppm of sanguinarine and chelerythrine in M. cordata extract, and 5, 330, or 660 ppm of total alkaloids in Sangrovit for 90 days. The DNA adducts formation in liver was analyzed by (32)P-postlabeling technique and DNA single strand breaks in lymphocytes were evaluated by Comet assay. The results showed that M. cordata extract and/or Sangrovit induced no DNA damage to rat lymphocytes or hepatocytes after 90-days oral administration. CONCLUSIONS: Data from the studies described in this paper and the fact that Sangrovit given to the rats in our experiments were higher than the recommended dose (50 to 100 mg/kg feed), argue strongly in favour of the use of Sangrovit in live stock.  (+info)

Impact of cytomixis on meiosis, pollen viability and pollen size in wild populations of Himalayan poppy (Meconopsis aculeata Royle). (8/21)

We report the occurrence of cytomixis in wild populations of Himalayan poppy (Meconopsis aculeata Royle),which is considered to be an important and threatened medicinal plant growing in the high hills of the Himalayas. The impact of cytomixis on meiotic behaviour, reduced pollen viability and heterogeneous-sized pollen grains was also studied. Cytological studies in the seven wild populations from the high hills of Himachal Pradesh revealed that all the Himalayan populations exist uniformly at the tetraploid level (2n=56) on x=14. The phenomenon of chromatin transfer among the proximate pollen mother cells (PMCs) in six populations caused various meiotic abnormalities. Chromatin transfer also resulted in the formation of coenocytes, aneuploid, polyploid and anucleated PMCs. Among individuals that showed chromatin transfer, chromosome stickiness and interbivalent connections were frequently observed in some PMCs. The phenomenon of cytomixis in the species seems to be directly under genetic control; it affects the meiotic course considerably and results in reduced pollen viability.  (+info)

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