Pedicularis
Acanthaceae
A novel iridoid from Boschniakia rossica. (1/38)
A novel iridoid, (4R)-4-hydroxymethylboschnialactone (1), has been isolated from Boschniakia rossica, together with three previously known compounds, (24S)-3beta-hydroxy-24-ethylcholest-5-en-7-one (2), (24R)-3beta-hydroxy-24-ethylcholest-5-en-7-one (3) and methyl p-coumarate, using column chromatography. The structures of compounds were elucidated by spectroscopic methods. (+info)In vitro infection of host roots by differentiated calli of the parasitic plant Orobanche. (2/38)
Root parasites of the genus Orobanche are serious weeds in agriculture. An aseptic infection system of host roots using calli of three Orobanche species was developed for the study of host-parasite interaction. The response of calli to various hormonal combinations was studied, because a requirement for infection is the differentiation of root-like protrusions, which are capable of producing haustorial connections to the host. Infectious root-like protrusions develop under the influence of 0.5-1.0 mg l(-1) IAA, and under the combination of 0.2 mg l(-1) NAA with 5.0 mg l(-1) kinetin. These protocols produced root protrusions with pad-like structures that resembled attachment organs of Orobanche seedlings, and proved effective in parasitizing host roots. Direct contact with the medium inhibited haustorium development and prevented infection. To overcome this problem, certain root portions were isolated from the medium by inserting thin glass plates underneath. Calli were then placed on the raised root portions and successfully infected the roots and developed young Orobanche tubercles with vascular system that directly connected to the host. (+info)Section-level relationships of North American Agalinis (Orobanchaceae) based on DNA sequence analysis of three chloroplast gene regions. (3/38)
BACKGROUND: The North American Agalinis are representatives of a taxonomically difficult group that has been subject to extensive taxonomic revision from species level through higher sub-generic designations (e.g., subsections and sections). Previous presentations of relationships have been ambiguous and have not conformed to modern phylogenetic standards (e.g., were not presented as phylogenetic trees). Agalinis contains a large number of putatively rare taxa that have some degree of taxonomic uncertainty. We used DNA sequence data from three chloroplast genes to examine phylogenetic relationships among sections within the genus Agalinis Raf. (=Gerardia), and between Agalinis and closely related genera within Orobanchaceae. RESULTS: Maximum likelihood analysis of sequences data from rbcL, ndhF, and matK gene regions (total aligned length 7323 bp) yielded a phylogenetic tree with high bootstrap values for most branches. Likelihood ratio tests showed that all but a few branch lengths were significantly greater than zero, and an additional likelihood ratio test rejected the molecular clock hypothesis. Comparisons of substitution rates between gene regions based on linear models of pairwise distance estimates between taxa show both ndhF and matK evolve more rapidly than rbcL, although the there is substantial rate heterogeneity within gene regions due in part to rate differences among codon positions. CONCLUSIONS: Phylogenetic analysis supports the monophyly of Agalinis, including species formerly in Tomanthera, and this group is sister to a group formed by the genera Aureolaria, Brachystigma, Dasistoma, and Seymeria. Many of the previously described sections within Agalinis are polyphyletic, although many of the subsections appear to form natural groups. The analysis reveals a single evolutionary event leading to a reduction in chromosome number from n = 14 to n = 13 based on the sister group relationship of section Erectae and section Purpureae subsection Pedunculares. Our results establish the evolutionary distinctiveness of A. tenella from the more widespread and common A. obtusifolia. However, further data are required to clearly resolve the relationship between A. acuta and A. tenella. (+info)Abscisic acid (ABA) flows from Hordeum vulgare to the hemiparasite Rhinanthus minor and the influence of infection on host and parasite abscisic acid relations. (4/38)
Using the facultative root hemiparasite Rhinanthus minor and Hordeum vulgare as a host, the flows, depositions, and metabolism of abscisic acid (ABA) within the host, within the parasite, and between host and parasite have been studied. When the plants were supplied with 5 mM NO(3)(-), there were weak or no effects of parasitism on ABA flows, biosynthesis, and ABA degradation in barley. However, ABA deposition was significantly affected in the leaf laminae (3-fold) and in the leaf sheath (2.4-fold), but not in roots. Dramatic changes in ABA flows, metabolism, and deposition on a per plant basis, however, have been observed in Rhinanthus. Biosynthesis in the roots was 12-fold higher after attachment, resulting in 14-fold higher ABA flows in the xylem. A large portion of this ABA was metabolized, a small portion was deposited. Phloem flows of ABA were increased 13-fold after attachment. The concentrations of ABA in tissues and transport fluids were higher in attached Rhinanthus by an order of magnitude than in host tissues and xylem sap. The same tendency was also found in a comparison between single Rhinanthus and unparasitized barley. As compared with 5 mM NO(3)(-), lower NO(3)(-) or 1 mM NH(4)(+) supply doubled the ABA concentrations in barley leaf laminae, while having only small or non-significant effects in the other organs. The possible function of ABA for the parasite is discussed. (+info)Treatment of pig serum-induced rat liver fibrosis with Boschniakia rossica, oxymatrine and interferon-alpha. (5/38)
AIM: To investigate the effect of Boschniakia rossica (BR), oxymatrine (OM) and interferon-alpha (IFN-alpha) 1b on the therapy of rat liver fibrosis and its mechanism. METHODS: By establishing a rat model of pig serum-induced liver fibrosis, liver/weight index and serum alanine transaminase (ALT) were observed to investigate the therapeutic effect of BR,OM and IFN-alpha. Radioimmunoassay was utilized to measure procollagen type III (PCIII) and collagen type IV (CIV). RT-PCR was used to assay the expression of liver transforming growth factor-beta 1 (TGF-beta1) mRNA. Immunohistochemistry of alpha-smooth muscle actin (alpha-SMA) and pathologic changes of liver tissues were also under investigation. RESULTS: Serum PCIII and CIV in BR, OM and IFN-alpha groups were significantly declined compared with those in model group, and their RT-PCR revealed that TGF-beta1 mRNA expression was also reduced more than that in model group. Immunohistochemistry demonstrated that alpha-SMA also declined more than that in model group. Serum ALT in IFN-alpha, control and model groups was within normal level. Serum ALT in BR group had no significant difference from those of IFN-alpha, control and model groups. Serum ALT in OM group was significantly higher than those in BR, IFN-alpha, model, and control groups. CONCLUSION: BR, OM and IFN-alpha can prevent pig serum-induced liver rat fibrosis by inhibiting the activation of hepatic stellate cells and synthesizing collagen. OM has hepatotoxicity to rat liver fibrosis induced by pig serum. (+info)Rate variation in parasitic plants: correlated and uncorrelated patterns among plastid genes of different function. (6/38)
BACKGROUND: The analysis of synonymous and nonsynonymous rates of DNA change can help in the choice among competing explanations for rate variation, such as differences in constraint, mutation rate, or the strength of genetic drift. Nonphotosynthetic plants of the Orobanchaceae have increased rates of DNA change. In this study 38 taxa of Orobanchaceae and relatives were used and 3 plastid genes were sequenced for each taxon. RESULTS: Phylogenetic reconstructions of relative rates of sequence evolution for three plastid genes (rbcL, matK and rps2) show significant rate heterogeneity among lineages and among genes. Many of the non-photosynthetic plants have increases in both synonymous and nonsynonymous rates, indicating that both (1) selection is relaxed, and (2) there has been a change in the rate at which mutations are entering the population in these species. However, rate increases are not always immediate upon loss of photosynthesis. Overall there is a poor correlation of synonymous and nonsynonymous rates. There is, however, a strong correlation of synonymous rates across the 3 genes studied and the lineage-speccific pattern for each gene is strikingly similar. This indicates that the causes of synonymous rate variation are affecting the whole plastid genome in a similar way. There is a weaker correlation across genes for nonsynonymous rates. Here the picture is more complex, as could be expected if there are many causes of variation, differing from taxon to taxon and gene to gene. CONCLUSIONS: The distinctive pattern of rate increases in Orobanchaceae has at least two causes. It is clear that there is a relaxation of constraint in many (though not all) non-photosynthetic lineages. However, there is also some force affecting synonymous sites as well. At this point, it is not possible to tell whether it is generation time, speciation rate, mutation rate, DNA repair efficiency or some combination of these factors. (+info)Pscroph, a parasitic plant EST database enriched for parasite associated transcripts. (7/38)
BACKGROUND: Parasitic plants in the Orobanchaceae develop invasive root haustoria upon contact with host roots or root factors. The development of haustoria can be visually monitored and is rapid, highly synchronous, and strongly dependent on host factor exposure; therefore it provides a tractable system for studying chemical communications between roots of different plants. DESCRIPTION: Triphysaria is a facultative parasitic plant that initiates haustorium development within minutes after contact with host plant roots, root exudates, or purified haustorium-inducing phenolics. In order to identify genes associated with host root identification and early haustorium development, we sequenced suppression subtractive libraries (SSH) enriched for transcripts regulated in Triphysaria roots within five hours of exposure to Arabidopsis roots or the purified haustorium-inducing factor 2,6 dimethoxybenzoquinone. The sequences of over nine thousand ESTs from three SSH libraries and their subsequent assemblies are available at the Pscroph database http://pscroph.ucdavis.edu. The web site also provides BLAST functions and allows keyword searches of functional annotations. CONCLUSION: Libraries prepared from Triphysaria roots treated with host roots or haustorium inducing factors were enriched for transcripts predicted to function in stress responses, electron transport or protein metabolism. In addition to parasitic plant investigations, the Pscroph database provides a useful resource for investigations in rhizosphere interactions, chemical signaling between organisms, and plant development and evolution. (+info)Rossicasins A, B and rosicaside F, three new phenylpropanoid glycosides from Boschniakia rossica. (8/38)
Three phenylpropanoid glycosides have been isolated, together with the known phenylpropanoid glycosides rossicaside A (4), B (5), E (6), and trans-p-coumaryl alcohol 1-O-beta-D-glucopyranosyl(1-->4)-alpha-L-rhamnopyranosyl(1-->3)-beta-D-glucopyran oside (7), and an acylated oligosaccharide beta-D-glucopyranosyl(1-->4)-alpha-L-rhamnopyranosyl-(1-->3)-(4-O-trans-caffeoyl) -D-glucopyranose) (8), from the aqueous extract of Boschniakia rossica (CHAM. et SCHLECH.) FEDTSCH. et FLEROV. Spectroscopic evidence led to the assignments of their structures as trans-p-coumaryl-(6'-O-beta-D-xylopyranosyl)-O-beta-D-glucopyranoside (1), trans-p-coumaryl-(6'-O-alpha-L-arabinopyranosyl)-O-beta-D-glucopyranoside (2) and 2-(3,4-dihydroxyphenyl)-R,S-2-ethoxy-ethyl-O-beta-D-glucopyranosyl(1-->4)-alpha-L -rhamnopyranosyl(1-->3)(4-O-trans-caffeoyl)-beta-D-glucopyranoside (3), designated as rossicasin A, rossicasin B, and rossicaside F, respectively. Compound 7 was identified from the degradation reaction and this is the first isolation from a natural source. (+info)Orobanchaceae is a family of flowering plants, also known as the broomrape family. These are parasitic or hemiparasitic plants, which means they derive some or all of their nutrients from other plants by attaching to their roots and tapping into their vascular systems.
The family includes both holoparasites, which are completely dependent on their host plants for nutrients, and facultative parasites, which can grow independently but benefit from parasitism.
Notable genera in this family include Striga (witchweeds), Orobanche (broomrapes), and Pedicularis (louseworts). Some members of this family can cause significant damage to agricultural crops, making them important subjects of study in the field of plant pathology.
Cistanche is a genus of plants in the family Orobanchaceae, also known as the broomrape family. It includes several species that are native to Asia and the Mediterranean region. One commonly used species is Cistanche deserticola, which is known in traditional Chinese medicine as Rou Cong Rong. This plant is a parasitic desert shrub that grows by tapping into the roots of other plants for nutrients.
In traditional Chinese medicine, extracts from the dried root of Cistanche deserticola are used to treat various conditions, such as impotence, constipation, and kidney deficiency. However, it's important to note that while some studies suggest potential health benefits of Cistanche, more research is needed to confirm its effectiveness and safety.
As with any supplement or medication, consult a healthcare professional before using Cistanche extract or any other products derived from this plant.
"Pediculus" is the medical term that refers to lice, specifically the human body louse (Pediculus humanus) and the head louse (Pediculus capitis). These tiny parasitic insects feed on human blood and are primarily found in the seams of clothing or on the hair shafts close to the scalp. Infestations with body or head lice, known as pediculosis, can cause itching and scratching, which may lead to skin irritation and infection. It is important to note that "Pedicularis" is also a genus of flowering plants, but in medical terminology, it specifically refers to lice.
Acanthaceae is a family of flowering plants that includes around 2,500 species distributed across 220-400 genera. These plants are primarily found in tropical and subtropical regions, with some extending into temperate zones. The family is characterized by the presence of stiff, spiny bracts, which are often colorful and modified to attract pollinators.
The plants in Acanthaceae can vary widely in form, from herbaceous annuals and perennials to shrubs and trees. They have simple or opposite leaves that may be entire or lobed. The flowers are typically bisexual, with a two-lipped calyx and corolla, and four stamens.
Some well-known members of Acanthaceae include the garden plants Shrimp Plant (Justicia brandegeeana) and Whorled Tubelet (Lepidagathis formosa), as well as the medicinal plant Indian Snakeroot (Rauvolfia serpentina).
In a medical context, some species of Acanthaceae have been used in traditional medicine for various purposes, such as treating skin conditions, fevers, and gastrointestinal disorders. However, it is important to note that the use of these plants should be done with caution and under the guidance of a qualified healthcare professional, as they can also contain toxic compounds.
DNA, or deoxyribonucleic acid, is the genetic material present in the cells of all living organisms, including plants. In plants, DNA is located in the nucleus of a cell, as well as in chloroplasts and mitochondria. Plant DNA contains the instructions for the development, growth, and function of the plant, and is passed down from one generation to the next through the process of reproduction.
The structure of DNA is a double helix, formed by two strands of nucleotides that are linked together by hydrogen bonds. Each nucleotide contains a sugar molecule (deoxyribose), a phosphate group, and a nitrogenous base. There are four types of nitrogenous bases in DNA: adenine (A), guanine (G), cytosine (C), and thymine (T). Adenine pairs with thymine, and guanine pairs with cytosine, forming the rungs of the ladder that make up the double helix.
The genetic information in DNA is encoded in the sequence of these nitrogenous bases. Large sequences of bases form genes, which provide the instructions for the production of proteins. The process of gene expression involves transcribing the DNA sequence into a complementary RNA molecule, which is then translated into a protein.
Plant DNA is similar to animal DNA in many ways, but there are also some differences. For example, plant DNA contains a higher proportion of repetitive sequences and transposable elements, which are mobile genetic elements that can move around the genome and cause mutations. Additionally, plant cells have cell walls and chloroplasts, which are not present in animal cells, and these structures contain their own DNA.
Phylogeny is the evolutionary history and relationship among biological entities, such as species or genes, based on their shared characteristics. In other words, it refers to the branching pattern of evolution that shows how various organisms have descended from a common ancestor over time. Phylogenetic analysis involves constructing a tree-like diagram called a phylogenetic tree, which depicts the inferred evolutionary relationships among organisms or genes based on molecular sequence data or other types of characters. This information is crucial for understanding the diversity and distribution of life on Earth, as well as for studying the emergence and spread of diseases.