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1.
Cytokines such as tumor necrosis factor (TNF) and Interleukin-1 (IL1) are known to influence energy metabolism and mitochondrial function in tumor and vascular smooth muscle cells. The aim of the present study was to investigate whether in cardiomyocytes mitochondrial function and PDH activity may also be impaired by TNF and IL1. Pyruvate dehydrogenase (PDH) activity and mitochondrial oxygen consumption of cultured cardiomyocytes were determined after subchronic exposure (24 h) to TNF (1, 10, 100, 1000 I.U./ml) and IL1 (0.1, 1, 10, 100 I.U./ ml).TNF- and IL1- exposure of the cardiomyocytes resulted in a concentration dependent decrease of PDH activity up to 38%. In parallel, selective oxygen consumption of the respiratory chain complexes I (NADH:ubiquinone oxidoreductase) and II (succinate:ubiquinone oxidoreductase) decreased by up to 45%. Addition of the PDH activator dichloracetate (0.01 M) resulted in complete restoration of PDH activity but not of mitochondrial function. The results suggest a primary inhibition of the mitochondrial respiratory chain by TNF and IL1 and a subsequent down regulation of PDH activity.  相似文献   

2.
Summary Bacillus subtilis -amylase signal peptide, which consists of 33 amino acids, is functional in Escherichia coli cells.Lysine, glutamic acid, leucine, leucyl-leucine, or leucyl-leucyl-leucine was inserted between positions 28 and 29 of the -amylase signal peptide using site directed mutagenesis. DNAs encoding the wild-type and modified signal peptides were then fused in-frame to DNAs encoding the mature regions of the -lactamase of pBR322 and a thermostable -amylase. The secretion of -lactamase in E. coli cells was more inhibited by the modified signal peptides than that in B. subtilis cells, although the degree of inhibition varied and the inhibitory effect of each signal peptide was found to be similar in the two strains. In contrast, the difference in the inhibitory effect of each modified signal peptide was no longer detected in the case of the production of thermostable -amylase, except for the insertion of glutamic acid. Nearly 50% of thermostable -amylase in the precursor form was accumulated in the intracellular fraction of E. coli cells containing the DNAs for the modified signal peptides. The insertion of glutamic acid inhibited the secretion of the two enzymes in both B. subtilis and E. coli cells.  相似文献   

3.
Summary -Thalassemia exists at a high prevalence in several regions of Saudi Arabia. The restriction endonucleases Bam HI and BglII were used to investigate the molecular basis of deletion type of -thalassemia in 226 subjects from the eastern and 61 subjects from the northwestern regions of the country. The arrangements-/ and-/- were common. BglII digestion revealed the existence of rightward deletion in a majority of the cases. Leftward deletions, both homozygous and heterozygous, were also identified. Triple -gene arrangements -/ and -/- were observed at a low frequency in both regions.  相似文献   

4.
Summary Addition of noradrenaline (4×10–5 m) to the inner bathing fluid in the skin of the frogRana esculenta results in increased unidirectional fluxes of urea, thiourea, N-methyl-thiourea, N-N-dimethylthiourea and mannitol. Fluxes towards the external medium ( 0) undergo a much greater increase than those moving in the opposite direction ( i ). The effect of noradrenaline on ( 0) is higher for urea and thiourea than mannitol, while its effect on ( 0) thiourea derivatives is related to lipid solubility. This phenomenon does not occur for ( i ) of the same molecules.FCCP (10–6 m) pretreatment strongly inhibits the noradrenaline effect on ( 0). In skin pretreated whith colchicine (2×10–5 m) both urea fluxes are increased to the same extent by noradrenaline. Noradrenaline is concluded to exert two separate effects: (1) a change in permeability in both directions; (2) a secretion of nonelectrolytes towards the external fluid. Such secretion is most probably associated with the hormone-induced secretion of fluid and electrolytes, perhaps mediated by an exocytotic mechanism.  相似文献   

5.
Phoma tracheiphila is the causative agent of the disease mal secco. Citrus cultivars differ substantially in respect to their sensitivity to the pathogenP. tracheiphila and its toxin. Some cultivars (e.g., Femminello lemon) are inherently sensitive while others (e.g., Tarocco orange) are tolerant. Cell lines derived from nucellar tissue of Femminello, Tarocco and a cell line selected for tolerance to the fungal toxin (Femminello-S) were used to study host-pathogen interaction. Our results showed that calli or conditioned media of Tarocco and Femminello-S inhibited the size of co-cultivated fungal colonies when compared to Femminello. In addition, conditioned medium of Tarocco as well as FemminelloS, but not Femminello, promoted bursting of hyphal tips. A ten-fold increase in chitinase and glucanase enzymatic activity, as evaluated by radiometric assay and laminarin hydrolysis respectively, was detected in Femminello-S extracellular extracts as compared to Femminello. An increase in chitinase was also shown by immunoblot analysis. Our findings suggest a positive correlation between the presence of chitinase and glucanase in the conditioned media of the cultured cells and the tolerance of those cells toP. tracheiphila toxin.  相似文献   

6.
The shoot organization and inflorescence structure ofEpithema is analyzed. On the main axis micro- and macrocotyledon (the latter falling off early) are followed by a ± long epicotyl, then a large, solitary leaf (B3) and above this a dimerous leaf whorl (B4, B5). The last internode of the main axis is the basic internode of the main florescence (Troll). Peculiarly enough, the latter includes only one partial florescence which is embraced by its subtending bract (B6) and represents a capitulum-like, congenital, pair-flowered cincinnus. Paracladia arise from the axils of B3 to B5 (sometimes also from the macrocotyledon); they are either reduced to their co-florescence (with the same structure as the main florescence), or carry further shoots resp. co-florescences from the axils of a dimerous leaf whorl.—Epithema can be interpreted as anisophyllous.—From flower morphology and ontogenesis a number of new differential characters are revealed. Together with shoot and inflorescence characters their systematic and possible functional significance is discussed.
Frau Univ.-Prof. Dr. E.Tschermak-Woess zum 60. Geburtstag gewidmet.  相似文献   

7.
Summary Isoelectric focusing of esterase (EST), peroxidase (PRX), and phosphoglucomutase (PGM) isozymes in Chinese Spring wheat, Imperial rye and several Chinese Spring/Imperial and Holdfast/King II addition, translocation and substitution lines revealed the chromosomal location of nine Est loci previously described and of one Prx and Pgm locus. Loci Est1, Est2, Est3, Est5, Est6 and Est7 were found on chromosome arm 5RL, Est8 and Est9 on chromosome 6R in Imperial rye, and the Est10 locus on chromosome arm 4RL in Imperial rye and King II rye. A discrepancy was found between the chromosomal location of the Prx locus in Imperial where chromosome 2R was responsible for the expression of the peroxidase enzyme, and King II with chromosome 1R carrying the Prx gene. As a possible explanation, the occurrence of translocation events during the production of wheat/rye aneuploid lines is discussed. The rye Pgm locus could be associated with chromosome 4RS in Imperial and King II rye. Except for the location of Est loci on chromosome 5RL, the results reported in this paper lend further evidence for the assumed homoeology relationships between the chromosomes of Triticinae and for the conservation of gene synteny groups during the evolution of the Triticeae tribe.  相似文献   

8.
Summary Using disomic chromosome substitution lines based on the susceptible wheat cultivar Chinese Spring, loose smut resistance of wheat cultivars Hope and Thatcher was shown to be conferred in each case by a single dominant major gene carried on chromosome 7 A (Hope) or 7 B (Thatcher). Partial resistance was determined by genes on an additional eight Hope or seven Thatcher chromosomes, and similarities were evident between the partial resistance genotypes ofHope and Thatcher. Chinese Spring exhibited a mean infection value of approximately 50%, indicating a significant level of partial resistance, which was found to be due, in part, to genes on the homoeologous chromosome arms 1 As, 1 Es and 1 Ds, and to cytoplasmic genes. Substitution of the Chinese Spring nucleus into the cytoplasm of Aegilops squarrosa, Ae. variabilis or Ae. mutica resulted in increased susceptibility to Ustilago tritici. Several alloplasmic lines of the resistant wheat cultivars Selkirk and Chris exhibited race-specific susceptibility to U. tritici.  相似文献   

9.
Ten previously unreported oligosaccharides have been purified from the urines of human subjects using a combination of gel filtration, ion exchange, and thin-layer chromatographies. Their structures were determined by direct probe mass spectrometry, methylation analysis, and proton NMR spectroscopy of the permethylated oligosaccharide alditols.On the basis of composition, the oligosaccharides could be divided into three groups. Five oligosaccharides containing glycerol were characterized as glucosyl1-1glycerol; glucosyl1-1glycerol; galactosyl1-1glycerol; glucosyl-1-1(fucosyl-1-2)glycerol and/or fucosyl-1-1(glucosyl-1-2)glycerol; and glucosyl-1-1(galactosyl-1-2)glycerol or galactosyl-1-1(glucosyl-1-2)glycerol. Four inositol-containing oligosaccharides were characterized as galactosyl1 (fucosyl1)inositol,N-acetylgalactosaminyl1 (fucosyl1)inositol, fucosyl1-2galactosyl1 (N-acetylgalactosaminyl1)inositol and fucosyl1-2galactosyl1-4-N-acetylglucosaminyl1(N-acetylgalactosaminyl1)inositol. Finally, galactosyl1-3(fucosyl1-2)galactosyl1-6galactosyl1-4(fucosyl1-3)glucose, an oligosaccharide with glucose at its reducing end, was tentatively identified. The significance and possible origins of the carbohydrate structures are discussed.  相似文献   

10.
Pre-emergence damping-off tests indicate that Pythiumspp. from pond water can be divided into two categories: avirulent Pythium (P. diclinum, P. marsipium, P. middletonii, P. monospermum, P. pleroticum, P. undulatum)and weakly virulent Pythium (P. catenulatum, P. coloratum, P. dissotocum, P. papillatum, Pythium Group F, Pythium group HS, Pythium group P, Pythiumgroup T). Post-emergence damping-off tests indicate that the pythia tested can also be divided into three categories: avirulent Pythium (P. catenulatum, P. dissotocum, P. marsipium, P. monospermum, P, papillatum, P. pleroticum, P. undulatum, Pythium group F, Pythium group T),weakly virulent Pythium (P. coloratum, P. diclinum, P. middletonii, Pythiumgroup P and moderately virulent Pythium (Pythium group HS).  相似文献   

11.
Quantitative trait loci (QTLs) affecting seed weight in pea (Pisum sativum L.) were mapped using two populations, a field-grown F2 progeny of a cross between two cultivated types (Primo and OSU442-15) and glasshouse-grown single-seed-descent recombinant inbred lines (RILs) from a wide cross between a P. sativum ssp. sativum line (Slow) and a P. sativum ssp. humile accession (JI1794). Linkage maps for these crosses consisted of 199 and 235 markers, respectively. QTLs for seed weight in the Primo x OSU442-15 cross were identified by interval mapping, bulked segregant analysis, and selective genotyping. Four QTLs were identified in this cross, demonstrating linkage to four intervals on three linkage groups. QTLs for seed weight in the JI1794 x Slow cross were identified by single-marker analyses. Linkage were demonstrated to four intervals on three linkage groups plus three unlinked loci. In the two crosses, only one common genomic region was identified as containing seed-weight QTLs. Seed-weight QTLs mapped to the same region of linkage group III in both crosses. Conserved linkage relationships were demonstrated for pea, mungbean (Vigna radiata L.), and cowpea (V. unguiculata L.) genomic regions containing seed-weight QTLs by mapping RFLP loci from the Vigna maps in the Primo x OSU442-15 and JI1794 x Slow crosses.  相似文献   

12.
Stable transformation of lettuce cultivar South Bay from cotyledon explants   总被引:2,自引:0,他引:2  
Transgenic plants of lettuce cultivar (cv.) South Bay were produced by using Agrobacterium tumefaciens vectors containing the -glucuronidase (GUS) reporter gene and the NPT II gene for kanamycin resistance as a selectable marker. High frequency of transformation, based on kanamycin resistance and assays for GUS expression, was obtained with 24 to 72-h-old cotyledon explants cocultivated for 48 h with Agrobacterium tumefaciens. After the cocultivation period, the explants were placed in selection medium containing 50 or 100 mg l–1 of kanamycin, 100 mg l–1 cefotaxime and 500 mg l–1 carbenicillin for 10 days. Surviving explants were transferred every 14 days on shoot elongation medium. Progenies of R0 plants demonstrated linked monogenic segregation for kanamycin resistance and GUS activity.Florida Agricultural Experiment Station Journal Series R-02231. This research was partially supported by CNPq/RHAE (Brazil).  相似文献   

13.
The chemical structure of lipid A, from the marine -proteobacterium Pseudoalteromonas haloplanktis 14393, a main product of lipopolysaccharide hydrolysis (1% AcOH), was determined using chemical methods and NMR spectroscopy. The lipid A was shown to be -1,6-glucosaminobiose 1,4-diphosphate acylated with two (R)-3-hydroxyalkanoic acid residues at C3 and C3 and amidated with one (R)-3-hydroxydodecanoyl and one (R)-3-dodecanoyloxydodecanoyl residue at N2 and N2, respectively.  相似文献   

14.
Regenerative potential of the calli of nineteen genotypes of Avena sativa, Avena nuda, Avena byzantina and one interspecific hybrid were compared over three successive cultures. Highly significant genotype and genotype × subculture interactions were observed. Among the highest plant regenerable genotypes were Corbit (first subculture); GAF/Park and 88Ab3073 (second subculture); and GAF/Park and 87Ab5932 (third subculture). These genotypes regenerated on an average 10 to 17 plants each from a 200 mg callus mass after a 30 to 45 proliferation period. GAF/Park, a progeny of an interspecific cross, regenerated plants at a significantly higher level (11.85 plants/rep), followed by the similarly performing A. sativa (6.23 plants) and A. nuda (5.06 plants) genotypes, which were significantly higher than the A. byzantina genotypes (2.07 plants). Four genotypes were tested for their adaptability to suspension culture and plant regeneration potential by separating their cells and cell clusters into two sizes: larger and smaller than 3 mm. Larger clusters yielded plants for three genotypes GAF/Park, 88Ab3073, and Tibor. The smaller clusters only regenerated plants for GAF/Park and 88Ab3073. From one gram of callus used to initiate suspensions of GAF/Park and 88Ab3073, 119.9 and 18.8 plants, respectively, were regenerated. The plants regenerated for various genotypes from agar-solidified or suspension culture experiments had normal growth and seed set. This study confirms high and sustained regenerative capabilities of GAF/Park, a restricted genotype due to the weedy Avena fatua genetic background and identifies alternative genotypes, especially 88Ab3073 for future tissue culture and transformation studies.  相似文献   

15.
Summary A new Hessian fly (Mayetiola destructor) resistance gene derived from Balbo rye and its transfer to hexaploid wheat via radiation-induced terminal and intercalary chromosomal translocations are described. Crosses between resistant Balbo rye and susceptible Suwon 92 wheat and between the F1 amphidiploids and susceptible TAM 106 and Amigo wheats produced resistant BC2F3 lines that were identified by C-banding analysis as being 6RL telocentric addition lines. Comparative chromosomal analyses and resistance tests revealed that the resistance gene is located on the 6RL telocentric chromosome. X-irradiated pollen of 6RL addition plants was used to fertilize plants of susceptible wheats TAM 106, TAM 101, and Vona. After several generations of selection for resistance, new sublines were obtained that were homogeneous for resistance. Thirteen of these lines were analyzed by C-banding, and three different wheat-6RL chromosomal translocations (T) were identified. Wheat chromosomes involved in the translocations were 6B, 4B, and 4A. Almost the complete 6RL arm is present in T6BS · 6BL-6RL. Only the distal half of 6RL is present in T4BS · 4BL-6RL, which locates the resistance gene in the distal half of 6RL. Only a very small segment (ca 1.0 m) of the distal region of 6RL is present in an intercalary translocation (Ti) Ti4AS · 4AL-6RL-4AL. The 6RL segment is inserted in the intercalary region between the centromere of chromosome 4A and the large proximal C-band of 4AL. The break-points of the translocations are outside the region of the centromere, indicating that they were induced by the X-ray treatment. All three translocations are cytologically stable and can be used directly in wheat breeding programs.Cooperative investigations of the Kansas Agricultural Experiment Station, Departments of Entomology and Plant Pathology, the Wheat Genetics Resource Center, Kansas State University, and the US Department of Agriculture, Agricultural Research Service. Contribution No. 91-117-JDeceased  相似文献   

16.
Three new major, race-specific, resistance genes to powdery mildew (Erysiphe graminis f. sp. hordei) were identified in three barley lines, RS42-6*O, RS137-28*E, and HSY-78*A, derived from crosses with wild barley (Hordeum vulgare ssp. spontaneum). The resistance gene origining from wild barley in line RS42-6*O, showed a recessive mode of inheritance, whereas the other wild barley genes were (semi)-dominant. RFLP mapping of these three genes was performed in segregating F2 populations. The recessive gene in line RS42-6*O, was localized on barley chromosome 1S (7HS), while the (semi)-dominant genes in lines RS137-28*E, and HSY-78*A, were localized on chromosomes 1L (7HL) and 7L (5HL), respectively. Closely linked RFLP clones mapped at distances between 2.6cM and 5.3 cM. Hitherto, specific loci for powdery mildew resistance in barley had not been located on these chromosomes. Furthermore, tests for linkage to the unlocalized resistance gene Mlp revealed free segregation. Therefore, these genes represent new loci and new designations are suggested: mlt (RS42-6*O), Mlf (RS137-28*E), and Mlj (HSY-78*A). Comparisons with mapped QTLs for mildew resistance were made and are discussed in the context of homoeology among the genomes of barley (H-vulgare), wheat (Triticum aestivum), and rye (Secale cereale). Duplications of RFLP bands detected in the neighbourhood of Mlf and mlt might indicate an evolutionary interrelationship to the Mla locus for mildew resistance.  相似文献   

17.
The 6.5 kb HindIII DNA fragment of the Lactococcus lactis subsp. cremoris H2 plasmid pDI21 was cloned into Escherichia coli POP13 with NM1149, and also directly into Lactococcus lactis subsp. lactis 4125 using a newly-constructed broad host-range vector pFX1. Proteinase was experessed in both transformed organisms. The proteinase resembles a PI type since it preferentially degraded -casein. The restriction map of the 6.5 kb proteinase gene fragment has minor differences from those of published plamid proteinase genes. High-efficiency electroporation with pFX1 provides a direct approach for gene cloning in lactococci.Abbreviations cfu colony forming units - HEPES N-[2-hydroxyethyl]piperazine-N-[2-ethanesulphonic acid] Dedicated to Prof. Dr. G. Drews on the occasion of his 65th birthday  相似文献   

18.
Summary Leaves of the in vitro grown potato cultivars Bintje, Berolina, Desiree, and Russet Burbank were wounded and co-cultivated with Agrobacterium strains having chimeric bar and nptII genes on a disarmed T-DNA. Each leaf from these cultivars formed numerous calli on kanamycin-containing medium, and almost all calli regenerated shoots. For Russet Burbank, it was necessary to include AgNO3 in the medium to obtain efficient shoot regeneration. The transformed plants have one to a few copies of the T-DNA, show NPT-II and PAT activities, and are resistant to high doses of the commercial preparation of phospinotricin (glufosinate). Almost no somaclonal variation was detected in trans-genic plants.  相似文献   

19.
Summary The inheritance of resistance to whitebacked planthopper Sogatella furcifera (Horvath) was studied in 21 rice varieties. Reactions of F1; F2 and F3 progenies of the crosses of 21 resistant varieties with the susceptible variety TN 1 revealed that a single dominant gene governs resistance in Mushkan 41, Santhi, Siahnakidar 195, SM2-34, Tirisurkh 251, Zirijowaian 245, 18, 24A, 39, 76 S, 78, 180, 213 B, 267, 293, CI 6037-4, NP97, S39 JKW and Bansphul. In varieties 65 and 274 A, resistance is governed by one dominant and one recessive gene which segregate independently of each other. Tests for allelism with the Wbph 1 gene originally identified in N 22 revealed that the dominant gene present in all the test varieties is the same as Wbph 1. Further studies are required to determine the allelic relationships of the recessive gene found in varieties 65 and 274 A.  相似文献   

20.
With increasing concentrations in the growth medium of the cyclization inhibitors nicotine or 2-(4-chlorophenylthio)-triethylamine hydrochloride (CPTA) the previously identified bicyclic carotenoids of Rhizobium lupini (2,3,2,3-tetrahydroxy-,-caroten-4-one and 2,3,2,3-tetrahydroxy-,-carotene) were successively replaced by hitherto unknown monocyclic carotenoids. By application of mass and nuclear magnetic resonance spectroscopy 3 carotenoids were identified as 2,3-trans-dihydroxy-,-caroten-4-one, 2,3-trans-dihydroxy-,-carotene, and 3-hydroxy-,-caroten-4-one. A further compound was tentatively established as (2- or 3-)monohydroxy-,-carotene. It was found that other inhibitors such as diphenylamine or 4-chloro-5-(dimethylamino)-2-,,(trifluoro-m-tolyl)-3-(2H)-pyridazinone (San 6706) did not affect the pigment pattern. The results are discussed in relation to carotenoid biosynthesis in Rhizobium lupini.Abbreviations CPTA 2-(4-chlorophenylthio)-triethylamine hydrochloride - San 6706 4-chloro-5-(dimethylamino)-2-,,-(trifluoro-m-tolyl)-3-(2H)-pyridazinone  相似文献   

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