Identification of genes differentially expressed in extraradical mycelium and ectomycorrhizal roots during Paxillus involutus-Betula pendula ectomycorrhizal symbiosis

The development of ectomycorrhizal symbiosis leads to drastic changes in gene expression in both partners. However, little is known about the spatial regulation of symbiosis-regulated genes. Using cDNA array profiling, we compared the levels of expression of fungal genes corresponding to approximately 1,200 expressed sequenced tags in the ectomycorrhizal root tips (ECM) and the connected extraradical mycelium (EM) for the Paxillus involutus-Betula pendula ectomycorrhizal association grown on peat in a microcosm system. Sixty-five unique genes were found to be differentially expressed in these two fungal compartments. In ECM, a gene coding for a putative phosphatidylserine decarboxylase (Psd) was up-regulated by 24-fold, while genes coding for urea (Dur3) and spermine (Tpo3) transporters were up-regulated 4.1- and 6.2-fold in EM. Moreover, urea was the major nitrogen compound found in EM by gas chromatography-mass spectrometry analysis. These results suggest that (i) there is a spatial difference in the patterns of fungal gene expression between ECM and EM, (ii) urea and polyamine transporters could facilitate the translocation of nitrogen compounds within the EM network, and (iii) fungal Psd may contribute to membrane remodeling during ectomycorrhiza formation.     

Control of potassium influx in roots of birch (Betula pendula) seedlings exposed to cadmium

The nutrient status of the root may be a factor of vital importancefor plant tolerance to changes in the environment. In this studythe effect of Cd on the K+ uptake of birch plants, starved andnon-starved of potassium, was examined. Changes in potassiuminflux of birch [Betula pendula) roots, with time, were examinedin birch plants introduced to a nutrient solution containing125/jM K+ after a K+-starvation period. Cadmium was introducedduring the K+-recovery period and the effects of the heavy metalon the development of the uptake pattern was studied. When noCd was present K+ influx, in previously K+-starved plants, increasedwith time and reached a maximum after 6 h. When 2 or 5//M Cdwas supplied simultaneously with potassium to the root, K+ influxwas unchanged during an 8 h K+-recovery period, and the K concentrationin the roots did not increase as was the case when the plantswere given K+ without Cd. In another experiment Cd supply (2//M)to K+-fed plants gave an immediate 50% decrease in K+ influx.However, after prolonged exposure to Cd (up to 20 h), K+ influxrecovered to the control value. Key words: Birch, cadmium, influx, potassium, regulation     

Localization and release of allergens from tapetum and pollen grains ofBetula pendula

Summary Although intact pollen grains are assumed to be the primary carrier of pollen allergens, specific immunoreactive components have been found in other aerosol fractions, e.g., starch grains and remains of tapetal cells Cryo-scanning-electron-microscopy results demonstrate the presence of a clear network of strands connecting the tapetum with the microspores. The distribution of protein in tapetal orbicules, pollen wall, and pollen cytoplasm was tested by histochemical stains for light microscopy and transmission electron microscopy. The protein is mainly localized at the apertures and starch grains in the cytoplasm of pollen and in the core and on the surface of tapetal orbicules. Monoclonal antibodies Bv-10, BIP3, and BIP4 have been used to locate the cellular sites of pollen and tapetal allergens inBetula pendula (syn.B. verrucosa). The application of rapid-freeze fixation prevented relocation of allergens from their native sites. The allergens are predominantly found in the starch grains and to lesser extent in the exine. We also tested interactions between mature birch pollen and human fluids: saliva, nostrils fluid, and eyes solution. The aim was to mimic more closely the in vivo situation during allergenic response. In all cases we observed several pollen grains that were burst and had released their cytoplasmic contents. In the nose the allergens are released from the pollen within minutes. In rhinitis, nasal pH is increased from the normal pH 6.0 to 8.0. When we used nasal fluid at pH 8.0, the number of ruptured pollen grains increased. The mechanism that might induce formation of small allergen-bearing particles from living plant cells is discussed.     

Content and Composition of Fatty Acids in Total Lipids from the Buds of Betula pubescens,B. pendula,and B. pendula var. carelica

Russian Journal of Plant Physiology - Absolute content and composition of fatty acids (FAs) in total lipids from the buds of white birch (Betula pubescens Ehrh.), silver birch (B. pendula Roth),...     

Flavonoids from shoots, roots and roots exudates of Brassica alba

Analysis of extracts obtained from shoots, roots and exudates of Brassica alba revealed the presence of 3,5,6,7,8-pentahydroxy-4'-methoxy flavone in shoots, as well as 2',3',4',5',6'-pentahydroxy chalcone and 3,5,6,7,8-pentahydroxy flavone in roots and exudates. Apigenin was also found in the shoots and roots, but not in the root exudates.     

Triterpenes and neolignans from the roots of Nannoglottis carpesioides

Seven oleanane-type triterpenes and two 8-O-4′-neolignans, along with five known compounds (three 28-noroleanane-type triterpenes, one sarratane triterpene, and one neolignan), were isolated from roots of Nannoglottis carpesioides. Their structures were elucidated by spectroscopic methods, including 1D and 2D NMR, HRMS, and CD. The absolute configurations of two triterpenes were determined by experimental and calculated circular dichroism (CD) and optical rotation values. Ten compounds were evaluated for their cytotoxicity against human promyelocytic leukaemia (HL-60) and human hepatoma (Hep-G2) cells using the MTT assay. The antioxidant activities of these compounds were assessed by ABTS radical-scavenging assays. Among the tested compounds, three compounds exhibited moderate radical-scavenging activity against ABTS⁺, with IC₅₀ values of 22.4, 17.4, and 23.2 μM, respectively.     

Flavonoids from the roots of Millettia erythrocalyx

From the roots of Millettia erythrocalyx, 6-methoxy-[2",3":7,8]-furanoflavanone, 2,5-dimethoxy-4-hydroxy-[2",3":7,8]-furanoflavan, and 3,4-methylenedioxy-2',4'-dimethoxychalcone were isolated, along with ten other known flavonoids. Their structures were elucidated on the basis of analyses of their spectroscopic data.     

Diterpenoids from the roots of Croton macrostachys

Three novel diterpenoids have been isolated from the roots of Croton macrostachys. The structure and stereochemistry of the compounds have been unambiguously settled as neoclerodan-5,10-en-19,6beta;20,12-diolide, 3alpha, 19-dihydroxytrachylobane, and 3alpha,18,19-trihydroxytrachylobane from detailed spectroscopic evidence.     

Spirostanols from the roots and rhizomes of Trillium tschonoskii

Two novel spirostanols, (23S,24R,25S)-18-norspirost-1,4,13-triene-21,23,24-triol-3,15-dione (1) and (23S,24S,25S)-spirost-5-ene-1β,3β,21,23,24-pentaol (2), a new natural product (3), and two known analogues (4 and 5) were isolated from the ethyl acetate-soluble portion of the ethanolic extract of Trillium tschonoskii Maxim. Their structures were elucidated by extensive spectroscopic analyses, and their cytotoxic activities on four kinds of human tumor cells were studied in vitro. Compound 4 showed significant cytotoxic activity against MCF-7 and A549 with IC₅₀ values of 6.16 ± 2.21 and 28.5 ± 11.5 μM, respectively, while 5 exhibited selective cytotoxicity against A549 with an IC₅₀ value of 13.0 ± 4.51 μM.     

Nortriterpenoids from the roots of Paeonia emodi

Chemical investigation of chloroform–ethyl acetate extract from the roots of Paeonia emodi yielded four hitherto unknown noroleanane triterpenoids (1–4) together with four known compounds (5–8). Their structures were established by analysis of spectroscopic data. Compounds 1–8 were evaluated for cytotoxic activities against human cancer cell lines A549, HL-60, HCT116 and ZR-75-30. Compounds 1, 2, 3, 6 and 7 showed modest cytotoxicity against HL-60, HCT116 and ZR-75-30.     

Coumarins from the roots of Prangos uloptera

Three new coumarins, 6-O-[β-d-apiofuranosyl-(1 → 6)-β-d-glucopyranosyl]-prenyletin, 3″-O-[β-d-apiofuranosyl-(1 → 6)-β-d-glucopyranosyl]-oxypeucedanin hydrate and 2″-O-[β-d-apiofuranosyl-(1 → 6)-β-d-glucopyranosyl]-oxypeucedanin hydrate, together with six known coumarins, 3″-O-[β-d-apiofuranosyl-(1 → 6)-β-d-glucopyranosyl]-heraclenol, 3″-O-(β-d-glucopyranosyl)-heraclenol, tortuoside, 3″-O-(β-d-glucopyranosyl)-oxypeucedanin hydrate, heraclenol and oxypeucedanin hydrate, have been isolated from the roots of Prangos uloptera, and the structures of these coumarins were unequivocally determined by spectroscopic means, notably UV, HRESIMS, and 1D and 2D NMR spectroscopy.     

Trinorditerpenes from the roots of Flueggea virosa

Two trinorditerpenes, flueggrenes A and B (1 and 2), have been isolated from the roots of Flueggea virosa. Their structures were established by extensive analyses of spectroscopic data. The isolates were evaluated for anti-HCV activity, as well as the inhibition of superoxide anion generation and elastase release in response to FMLP/cytochalasin B.     

Isoflavonoids from the roots of Erythrina poeppigiana

Five isoflavonoids, 7,4′-dihydroxy-2′-methoxy-8-(γ,γ-dimethylallyl)isoflav-3-ene, 4′-hydroxy-2′-methoxy-6″,6″-dimethylpyran[2″,3″:7,8]isoflav-3-ene, 5,7,4′-trihydroxy-2′-methoxy-5′-(γ,γ-dimethylallyl)isoflavanone, 5,4′-dihydroxy-7,2′-dimethoxy-5′-(γ,γ-dimethylallyl)isoflavanone and 3,9-dihydroxy-4-(γ,γ-dimethylallyl)pterocarpene as well as six known compounds were isolated from the roots of Erythrina poeppigiana. Their structures were established on the basis of spectroscopic evidence.     

Lignans from the roots of Echinops giganteus

Two new lignans, (+)-4-(3-methylbutanoyl)-2,6-di(3,4-dimethoxy)phenyl-3,7-dioxabicyclo[3.3.0]octane and (+)-4-hydroxy-2,6-di(3,4-dimethoxy)phenyl-3,7-dioxabicyclo[3.3.0]octane, together with the known lupeol and sitosteryl beta-D-glucopyranoside, have been isolated from the roots of Echinops giganteus var. lelyi C. D. Adams (Compositae). The structures were elucidated on the basis of spectral studies and comparison with published data.     

Naphthoquinones from the roots of Aloe secundiflora

Two new naphthoquinones, 5-hydroxy-3,6-dimethoxy-2-methylnaphthalene-1,4-dione and 5,8-dihydroxy-3-methoxy-2-methylnaphthalene-1,4-dione, were isolated from the roots of Aloe secundiflora together with the known compounds chrysophanol, helminthosporin, isoxanthorin, ancistroquinone C, aloesaponarins I and II, aloesaponols I and II, laccaic acid d methyl ester and asphodelin. The structures were elucidated based on spectroscopic evidence. This appears to be the first report on the occurrence of naphthoquinones in the genus Aloe. Aloesaponarin I and 5-hydroxy-3,6-dimethoxy-2-methylnaphthalene-1,4-dione showed anti-bacterial activity against Mycobacterium tuberculosis with MIC values of 21–23 μg/mL in the Microplate Alamar Blue Assay (MABA) and Low Oxygen Recovery Assay (LORA); 5-hydroxy-3,6-dimethoxy-2-methylnaphthalene-1,4-dione also showed cytotoxicity against the Vero cell line (IC₅₀ = 10.2 μg/mL).