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151.
Diurnal oscillations of steady-state mRNA levels encoding the chlorophyll a/b-binding proteins were monitored inLycopersicon esculentum, Glycine max, Phaseolus vulgaris, P. aureus, P. coccineus, Pisum sativum, Sinapis alba, Hordeum vulgare,
Triticum aestivum andZea mays. In these plant speciescab mRNA accumulation increases and decreases periodically indicating i) that the expression of the genes for chlorophyll a/b-binding
proteins (cab genes) is controlled by a circadian rhythm, and ii) that the rhythm is widely distributed among monocotyledonous and dicotyledonous
plant species. A detailed characterization of the pattern ofcab mRNA expression in tomato leaves shows that the amplitude of the oscillation is dependent on i) the developmental stage of
the leaves, ii) the circadian phase and duration of light and iii) the circadian phase and duration of darkness. In addition
to the chlorophyll a/b-binding proteins, genes coding for other cellular functions were examined for cyclic variations of
their mRNA levels. The analysis includes genes involved in i) carbon metabolism (e.g. phosphoenolpyruvate carboxylase, pyruvate
orthophosphate dikinase, alpha amylase, fructose-1,6-bisphosphate aldolase, triosephosphate isomerase), ii) photosynthesis
(large and small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase, QB-binding protein, reaction-center protein of photosystem I) and iii) other physiological or morphological reactions (e.g.
ubiquitin, actin). However, no periodic fluctuation pattern was detected for the mRNA levels of these genes in tomato and
maize leaves. 相似文献
152.
V. I. Yermolaev G. I. Karasik T. M. Khlebodarova N. M. Matveeva M. R. Mullakandov A. M. Nayakschin T. V. Shumny N. B. Rubtsov O. L. Serov O. K. Baranov 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1989,78(1):93-96
Summary Using cloned cDNA for human 2-macroglobulin (A2M) as a probe, mink-Chinese hamster hybrid cells were analysed. The results allowed us to assign a gene for A2M to mink chromosome 9. Breeding tests demonstrated that the Lpm-locus coding for other related -macroglobulin protein and the gene for peptidase B (PEPB) are linked 11±3 cm apart. The PEPB gene is located on mink chromosome 9, and hence, the Lpw-locus is on the same mink chromosome. The relationship of the genetic systems controlling the isotypically different -macroglobulins in mink serum are discussed. 相似文献
153.
Saki Itonori Kazuya Hidari Yutaka Sanai Masaru Taniguchi Yoshitaka Nagai 《Glycoconjugate journal》1989,6(4):551-560
The effect of the chain length of the fatty acid residue of the ceramide moiety of ganglioside GM3 on the binding ability of monoclonal antibody M2590, which is specific for the carbohydrate structure of GM3-ganglioside, was examined by means of a direct binding assay on thin layer chromatography plates (TLC immunostaining) and a quantitative enzyme-linked immunosorbent assay (ELISA). Derivatives of GM3 with a long fatty acid chain reacted with the M2590 antibody, but those with a short fatty acid chain showed no reaction in either assay system. These results suggested that the acyl fatty acid moiety of the ganglioside played an important role in the formation or maintenance of the antigenic structure of the carbohydrate moiety of the ganglioside. 相似文献
154.
Cecilia PC Soh Alastair SR Donald James Feeney Walter TJ Morgan Winifred M Watkins 《Glycoconjugate journal》1989,6(3):319-332
The tetrasaccharides GalNAcß1-4[NeuAc2-3]Galß1-4Glc and GalNAcß1-4[NeuAc2-3]Galß1-4GlcNAc were synthesised by enzymic transfer of GalNAc from UDP-GalNAc to 3-sialyllactose (NeuAc2-3Galß1-4Glc) and 3-sialyl-N-acetyllactosamine (NeuAc2-3Galß1-4GlcNAc). The structures of the products were established by methylation and1H-500 MHz NMR spectroscopy. In Sda serological tests the product formed with 3-sialyl-N-acetyllactosamine was highly active whereas that formed with 3-sialyllactose had only weak activity. 相似文献
155.
Linda Owers Narhi Michael F. Rhode Pamela Hunt Tsutomu Arakawa 《Journal of Protein Chemistry》1989,8(5):669-677
The limited proteolysis of human recombinant TNF- by trypsin yields two stable products resulting from cleavage after Arg6 and Arg44. In solution these two products remain associated together in a trimer with a Stokes' radius slightly greater than the radius of intact TNF- and, therefore, could not be separated from each other under nondenaturing conditions. This limited digest retains at least 20% of the activity of the original TNF- sample, and has a tertiary structure that is similar to that of the native protein by circular dichroism. On the other hand, incorrectly folded, inactive TNF- undergoes extensive digestion following similar treatment with trypsin. These results indicate that the active form of TNF- has a tight core structure which is maintained afterN-terminal cleavage and removal. 相似文献
156.
Ossarath Kol Colette Brassart Geneviéve Spik Jean Montreuil Stéphane Bouquelet 《Glycoconjugate journal》1989,6(3):333-348
We have previously shown that an endo--N-acetylglucosaminidase (EC 3.2.1.96) named Endo B, isolated from culture filtrates of the basidiomyceteSporotrichum dimorphosporum cleaves asialo-, and to some extent, monosialylated bi-antennary glycans of theN-acetyllactosamine type linked to the asparagine residue of peptide or protein moieties [Bouquelet S, Strecker G, Montreuil J, Spik G (1980) Biochimie 62:43–49]. In the present paper, the substrate specificity of the enzyme towards oligomannoside and hybrid type glycans has been analyzed. The results obtained indicate that ovalbumin glycopeptides containing four to seven mannose residues and bovine lactotransferrin glycopeptides containing four to nine mannose residues were completely hydrolyzed by the enzyme. The degree of cleavage was variable among hybrid type structures, since glycopeptides containing the following glycans: (Gal)1(GlcNAc)3(Man)5(GlcNAc)2; (GlcNAc)3(Man)5(GlcNAc)2; (GlcNAc)3(Man)4(GlcNAc)2 were not hydrolyzed by the enzyme while the percentage of hydrolysis of a glycopeptide containing (GlcNAc)2(Man)5(GlcNAc)2 glycan reached 90%. The bovine lactotransferrin was partially deglycosylated (40%) in the absence of non-ionic detergent while native ovalbumin glycoprotein was not hydrolyzed by the enzyme.The oligomannoside-and theN-acetyllactosamine-type degrading activities present in the culture filtrates were not separated at any step of the purification procedure. Both activities were eluted as a single component with an apparent molecular mass of 89 kDa suggesting that they are located on the same enzyme molecule.Endo B represents a powerful tool for removing oligomannoside-andN-acetyllactosamine-type glycans fromN-glycopeptides andN-glycoproteins. Moreover, advantages in the use of Endo B in a soluble form as well as in an immobilized form result in its high activity and in its stability to heat denaturation and storage.Abbreviations Gal
d-galactose
- Man
d-mannose
- GlcNAc
N-acetyl-d-glucosamine
- Con A
concanavalin A
- Asn
asparagine
- GLC
gas liquid chromatography
- TLC
thin layer chromatography
- Endo
endo--N-acetylglucosaminidase
- Endo B
endo--N-acetylglucosaminidase isolated fromSporotrichum dimorphosporum
- PBE
polybuffer exchanger
- SDS-PAGE
sodium dodecylsulfate-polyacrylamide gel electrophoresis 相似文献
157.
158.
Belinda Martineau H. Jane Smith Caroline Dean Pamela Dunsmuir John Bedbrook Laurens J. Mets 《Plant molecular biology》1989,13(4):419-426
We report the successful transformation, via Agrobacterium tumefaciens infection, and regeneration of two species of the genus Flaveria: F. brownii and F. palmeri. We document the expression of a C3 plant gene, an abundantly expressed ribulose 1,5-bisphosphate carboxylase/oxygenase small subunit gene isolated from petunia, in these C4 plants. The organ-specific expression of this petunia gene in Flaveria brownii is qualitatively identical to its endogenous pattern of expression. 相似文献
159.
Ulrik Pedersen-Bjergaard Lars B geskov Nielsen Kai Jensen Lars Edvinsson Inger Jansen Jes Olesen 《Peptides》1989,10(6):1147-1152
Neurokinin A (NKA), substance P (SP) and the two peptides combined (SP + NKA) were injected intracutaneously on the forearm and into the temporal muscle of healthy volunteers. Pain intensity, cutaneous wheal and flare responses and tenderness of the temporal muscle were quantitated. SP but not NKA induced cutaneous pain. This relates the algesic effect of SP to the specific N-terminal amino acid sequence of the peptide, not shared by NKA. NKA, however, potentiated the algesic effect of SP as SP + NKA induced a significantly prolonged cutaneous pain sensation. Both peptides induced wheals, but only SP induced flare. These results confirm previous studies relating wheal formation to the identical C-terminal amino acid sequence of the two peptides and flare reaction to the N-terminal part of SP. Injections into the temporal muscle did not cause pain or tenderness. 相似文献
160.
Cellular origin and distribution of transforming growth factor-β1 in the normal rat myocardium 总被引:6,自引:0,他引:6
Dr. M. Eghbali 《Cell and tissue research》1989,256(3):553-558
Summary Transforming growth factor- (TGF-) is a biologically active polypeptide present in normal tissues as well as transformed cells. Two structurally related forms of this peptide are TGF-
1 and TGF-
2. Using freshly isolated cardiomyocytes and non-myocyte heart cells, and a [32P]-labelled cDNA probe to human TGF-
1, we demonstrated that mRNA for TGF-
1 could be detected only in the nonmyocyte fraction of heart cells. In the present study, the distribution of TGF-
1 in the heart was determined by immunofluorescence staining by use of a polyclonal antibody to porcine TGF-
1 in cryostat sections of rat heart. Immunofluorescence staining was intense around the blood vessels and radially diffuse in the surrounding myocardium. 相似文献