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61.
Enhanced quantitative resistance against fungal disease by combinatorial expression of different barley antifungal proteins in transgenic tobacco 总被引:26,自引:1,他引:25
Guido Jach Birgit Görnhardt John Mundy Jürgen Logemann Elke Pinsdorf Robert Leah Jeff Schell Christoph Maas 《The Plant journal : for cell and molecular biology》1995,8(1):97-109
cDNAs encoding three proteins from barley ( Hordeum vulgare ), a class-II chitinase (CHI), a class-II β-1,3-glucanase (GLU) and a Type-I ribosome-inactivating protein (RIP) were expressed in tobacco plants under the control of the CaMV 35S-promoter. High-level expression of the transferred genes was detected in the transgenic plants by Northern and Western blot analysis. The leader peptides in CHI and GLU led to accumulation of these proteins in the intercellular space of tobacco leaves. RIP, which is naturally deposited in the cytosol of barley endosperm cells, was expressed either in its original cytosolic form or fused to a plant secretion peptide (spRIP). Fungal infection assays revealed that expression of the individual genes in each case resulted in an increased protection against the soilborne fungal pathogen Rhizoctonia solani , which infects a range of plant species including tobacco. To create a situation similar to 'multi-gene' tolerance, which traditional breeding experience has shown to provide crops with a longer-lasting protection, several of these antifungal genes were combined and protection against fungal attack resulting from their co-expression in planta was evaluated. Transgenic tobacco lines were generated with tandemly arranged genes coding for RIP and CHI as well as GLU and CHI. The performance of tobacco plants co-expressing the barley transgenes GLU/ CHI or CHI/RIP in a Rhizoctonia solani infection assay revealed significantly enhanced protection against fungal attack when compared with the protection levels obtained with corresponding isogenic lines expressing a single barley transgene to a similar level. The data indicate synergistic protective interaction of the co-expressed anti-fungal proteins in vivo . 相似文献
62.
Using an immunoblotting technique and goat antihuman C4, we observed five distinct electrophoretic variants of C4 in a panel of 60 random dogs. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of immunoprecipitated C4 showed that dog C4 is composed of three polypeptide subunit chains (, , and ) and that structural variability occurs within the - and -chain regions. Two distinct molecular weight forms of both the C4- (
A and
B) and C4-(
A and
B) chain were detected. The variant forms of C4 and C4 were found in association with particular C4 allotypes. 相似文献
63.
Renata Brelińska Prof. Dr. Christoph Pilgrim Ingrid Reisert 《Cell and tissue research》1984,236(3):661-667
Summary Male Wistar rats were injected intravenously with 5-(3H)uridine-labeled lymphocytes isolated from lymph nodes of syngeneic donors and enriched in T cells. After short periods of time (3 to 120 min after injection), labeled lymphocytes were localized in spleen compartments using autoradiography to identify routes of lymphocyte movement from blood into splenic parenchyma and to follow migration pathways of recirculating lymphocytes within the periarterial lymphoid sheath (PALS). Topographical analysis of labeled lymphocytes was performed in specific planes of PALS characterized by the diameter of the arterial vessel and termed PALS large, PALS medium, and PALS small (PALS L, PALS M, PALS S, respectively). Attention was also paid to accumulations of labeled lymphocytes close to the arterial vessel wall. Initially, labeled lymphocytes were localized in PALS S and PALS M near the terminal branching of arterial vessels and in the marginal zone (MZ). We conclude that lymphocytes emigrate from blood into splenic parenchyma within two white pulp compartments: in MZ, and directly within PALS through the wall of capillary vessels. The sequential accumulation of labeled cells near arterial vessels of increasing diameter suggests that the recirculating pool of lymphocytes migrates into the central part of PALS L by two routes: from MZ, and along arterial vessels from PALS S and PALS M.R.B. was a fellow of the Alexander von Humboldt-Stiftung, on leave from the Department of Histology and Embryology, Institut of Biostructure, Academy of Medicine, ul. Swiecickiego 6, PL-60-781 Pozna, Poland. 相似文献
64.
Complexes of Escherichia coli lac-repressor with non-operator DNA have been visualized in the electron microscope using high-resolution metal shadowing and negative staining. Under conditions of a high ratio of repressor to DNA, all the DNA molecules are covered by repressor molecules and the resulting complexes appear as flattened ribbons with a width of approximately 200 Å. The overall dimensions of these complexes and their substructure indicate that it is very likely that repressor molecules are tightly packed on both “sides” of the DNA helix. Thus two repressor molecules can share the same segment of non-operator DNA by binding to opposite sides of the DNA helix. 相似文献
65.
Limited chymotryptic cleavage of soluble chicken gizzard desmin protofilaments allows the characterization of three structurally distinct domains. A surface-exposed very basic amino-terminal region (the headpiece) with an amino acid sequence excluding a-helical organization (7.5 kd) is separated from the perhaps globular carboxy-terminal 48 residues (the tailpiece) by a distinctly different middle domain of approximately 330 residues. This 38 kd domain is very rich in α-helix (at least 83%), and electron microscopy reveals a thin rod with a length of 500 ± 50 Å. Amino acid sequence data also show that the rod domain is interrupted by a nonhelical portion. An a-helical array is able to form a coiled-coil spanning the carboxy-terminal half of the 38 kd domain. The a-type diffraction pattern of 10 nm filaments arises from a coiled-coil conformation displayed through most but not all of the middle domain of the protofilaments. 相似文献
66.
The role of de novo synthesis in the regulation of adenosine 5-phosphosulfate sulfotransferase activity by H2S inLemna minor L. was investigate using density labeling with15N applied as15NO
3
–
in the culture medium. While adenosine 5-phosphosulfate sulfotransferase activity was rapidly reduced by H2S and rapidly recovered upon removal of H2S, O-acetyl-L-serine sulfhydrylase (EC 4.2.99.8) did not show changes in extractable activity in response to H2S and could therefore be used as an internal marker enzyme for density labeling. The incorporation of15N into adenosine 5-phosphosulfate sulfotransferase was strongly reduced upon transfer of plants into a H2S-containing atmosphere. Half-maximal labeling was reached only after 70–80 h compared to 40–50 h in the control. After removal of H2S, adenosine 5-phosphosulfate sulfotransferase activity increased to the initial level within 20 h, and the enzyme reached halfmaximal labeling after only 15 h. The time course of the density increase of O-acetyl-L-serine sulfhydrylase was not affected very significantly by H2S. These results provide evidence that de novo synthesis of enzyme protein is involved in the regulation of adenosine 5-phosphosulfate sulfotransferase activity by H2S.Abbreviations APS
adenosine 5-phosphosulfate
- APSSTase
adenosine 5-phosphosulfate sulfotransferase
- BSA
Bovine serum albumine
- DTE
dithioerythritol
- OAS
O-acetyl-L-serine
- OASSase
O-acetyl-L-serine sulfhydrylase
- POPOP
1,4-bis-(5-phenyl-2-oxazolyl)-benzene
- PPO
2,5-diphenyloxazole
This is no. 9 in the series Regulation of Sulfate Assimilation in Plants 相似文献
67.
68.
Ewa Stach-Chilf Jerzy B. Warchol Prof. Dr. Christoph Pilgrim 《Cell and tissue research》1981,219(2):417-423
Summary The neurohypophysis of donor mice was implanted under the renal capsule of the recipients. The pituicytes survived while the neurosecretory axons disappeared. The ultrastructure of the glial cells was observed seven and nine weeks after transplantation. There were no signs of phagocytotic activity although remnants of axons were still present at seven weeks. The numerous processes of the pituicytes form a network with intercellular spaces wide in younger and narrower in older implants. The cells are connected by desmosomes and gap junctions. Pituicytes as well as blood vessels preserve their organotypic appearance. The transplant thus represents an experimental model for investigations on pituicytes in vivo in the absence of neurosecretory axons.Fellow of the Alexander von Humboldt-Stiftung. On leave from Department of Histology and Embryology, Institute of Biostructure, Academy of Medicine, Pozna, Poland 相似文献
69.
70.