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Pierre Ferrer Michéle Crozatier Catherine Salles Alain Vincent 《Journal of molecular evolution》1994,38(3):263-273
The Drosophila serendipity (sry) and genes, which resulted from a gene duplication event, provide an interesting model for the evolutionary diversification in structure and function of C2H2 zinc finger proteins. We examined here the divergence of the sry and proteins over an estimated period of 45 million years by comparing their predicted sequences in D. melanogaster, D. pseudoobscura, and D. subobscura. Between orthologs, i.e., pairs of either sry or sry , the NH2-proximal region delineated by pairs of C-X2-C motifs and the DNA-binding finger domain are highly conserved. Sequence conservation operates over the entire finger domain, including the links separating adjacent fingers, even though each has a unique sequence different from the widespread TGEKP motif. In contrast, the sequence of the central acidic region has extensively diverged and differs between species in the number of amino acids, probably because of slippagedriven mutations. The NH2-terminal region and fingers 1, 5, and 6 differentiate the sry and proteins while zinc fingers 2, 3, and 4 are virtually identical in these two paralogs. A nuclear localization signal of the SV40T antigen type, preceded by a potential CKII phosphorylation regulatory site, is conserved in sry but not found in sry . The interspecific conserved regions correlate well with the positions of zygotic lethal mutations in the D. melanogaster sry protein. Furthermore, P-element transformation experiments show that a transgenic copy of the D. pseudoobscura sry gene rescues the sry mutant phenotype. Convergence of genetic and structural data on the sry proteins supports a multimodular function and mode of evolution of these C2H2 finger proteins.Abbreviations CKII
casein kinase II
-
D.m, D.p, D.s
Drosophila melanogaster, D. pseudoobscura and D. subobscura, respectively
- NLS
nuclear localization signal
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sry
serendipity
Correspondence to: A. Vincent 相似文献
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T. V. Malyarenko A. A. Kicha N. V. Ivanchina A. I. Kalinovsky P. S. Dmitrenok A. V. Smirnov 《Russian Journal of Bioorganic Chemistry》2010,36(6):755-761
Thirteen steroidal compounds including three new polyhydroxysteroids, (24R,25S)-24-methyl-5α-cholestane-3β,6α,8,15β,16β,26-hexaol, (22E,24R,25S)-24-methyl-5α-cholest-22-ene-3β,6α,8,15β,16β,26-hexaol, and (22E,24R,25S)-24-methyl-5α-cholest-22-ene-3β,4β,6α,8,15β,16β,26-heptaol, have been isolated along with ten previously known polyhydroxysteroids
from the tropical starfish Asteropsis carinifera collected near the coast of Vietnam. The structures of the new compounds were elucidated by spectroscopic methods (mainly
2D NMR and ESI mass spectrometry). 相似文献
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An DS Cui CH Sung BH Yang HC Kim SC Lee ST Im WT Kim SG 《Applied microbiology and biotechnology》2012,94(3):673-682
The gene encoding an α-l-arabinofuranosidase that could biotransform ginsenoside Rc {3-O-[β-d-glucopyranosyl-(1–2)-β-d-glucopyranosyl]-20-O-[α-l-arabinofuranosyl-(1–6)-β-d-glucopyranosyl]-20(S)-protopanaxadiol} to ginsenoside Rd {3-O-[β-d-glucopyranosyl-(1–2)-β-d-glucopyranosyl]-20-O-β-d-glucopyranosyl-20(S)-protopanaxadiol} was cloned from a soil bacterium, Rhodanobacter ginsenosidimutans strain Gsoil 3054T, and the recombinant enzyme was characterized. The enzyme (AbfA) hydrolyzed the arabinofuranosyl moiety from ginsenoside
Rc and was classified as a family 51 glycoside hydrolase based on amino acid sequence analysis. Recombinant AbfA expressed
in Escherichia coli hydrolyzed non-reducing arabinofuranoside moieties with apparent K
m values of 0.53 ± 0.07 and 0.30 ± 0.07 mM and V
max values of 27.1 ± 1.7 and 49.6 ± 4.1 μmol min−1 mg−1 of protein for p-nitrophenyl-α-l-arabinofuranoside and ginsenoside Rc, respectively. The enzyme exhibited preferential substrate specificity of the exo-type
mode of action towards polyarabinosides or oligoarabinosides. AbfA demonstrated substrate-specific activity for the bioconversion
of ginsenosides, as it hydrolyzed only arabinofuranoside moieties from ginsenoside Rc and its derivatives, and not other sugar
groups. These results are the first report of a glycoside hydrolase family 51 α-l-arabinofuranosidase that can transform ginsenoside Rc to Rd. 相似文献
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E. V. Levina D. L. Aminin S. N. Kovalchuk V. B. Kozhemyako S. A. Dyshlovoi A. I. Kalinovskii P. S. Dmitrenok 《Russian Journal of Bioorganic Chemistry》2010,36(2):233-239
Four polyhydroxylated steroids, new (20R)-5α-cholestan-3β,6α,8,15α,24,26-hexaol (I) and known (20R,25S)-5α-cholestan-3β,6α,8,15β,16β,26-hexaol, (20R,25S)-5α-cholestan-3β,6α,15β,16β,26-pentaol, and marthasterone sulfate were isolated from the Solaster endeca starfish inhabiting the Sea of Okhotsk and characterized. Steroid (I) contains a 24,26-dihydroxylated side chain, which is unique for starfish polyols. The isolated steroids and related metabolites
from two starfish species of the Evasterias genus (in total, 15 compounds) were weakly cytotoxic in a human HeLa cell culture and some of them were inhibitors of non-specific
esterase from mouse Ehrlich carcinoma. The effects of these compounds on the p53 protein activity were studied in a yeast
two-hybrid test system and both inhibitors and stimulators of this activity were found among them. 相似文献
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When α-d-GlcNAc-OC6H4NO2
-p and β-d-(6-sulfo)-GlcNAc-OC6H4NO2-p (2) were used as substrates, β-N-acetylhexosaminidase from Aspergillus oryzae transferred the β-d-(6-sulfo)-GlcNAc(unit from 2 to α-d-GlcNAc-OC6H4NO2
-p to afford β-d-(6-sulfo)-GlcNAc-(1→4)-α-d-GlcNAc-OC6H4NO2-p (3) in a yield of 94% based on the amount of donor, 2, added. β-d-(6-sulfo)-GlcNAc-(1→4)-α-d-Glc-OC6H4NO2-p (4) was obtained with α-d-Glc-OC6H4NO2
-p as acceptor in a similar manner. With a reaction mixture of 2 and β-d-GlcNAc-OC6H4NO2-p (1) in a molar ratio of 6:1, the enzyme mediated the transfer of β-d-GlcNAc from 1 to 2, affording disaccharide β-d-GlcNAc-(1→4)-β-(6-sulfo)-d-GlcNAc-OC6H4NO2-p (5) in a yield of 13% based on the amount of 1 added. 相似文献
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It is crucial to select stable references in gene expression analyses using quantitative real-time PCR (qRT-PCR). In this
work, seven frequently used reference genes, 18S, Actin, EF1α, α-tubulin, β-tubulin, Cyclophilin and Cytoplasmic ribosomal protein L2 (L2), from Bupleurum chinense DC. were evaluated as the internal control in five tissues, roots, stems, leaves, flowers and fruits, before tissue specific
gene expression assays. The results showed that β-tubulin was the most stable and reliable reference gene among the seven candidate genes in the measured tissues. The expression levels
of four genes involved in saikosaponins (the pharmacological active compounds of B. chinense) biosynthesis, HMGR, IPPI, FPS and β-AS, were assayed with β-tubulin as the internal control in the five tissues. All the four genes were expressed in the five tissues with different profiles
and HMGR in the order of roots > flowers, stems and leaves > fruits, IPPI of stems > leaves and fruits > roots and flowers, FPS of flowers > fruits > stems and roots > leaves and β-AS of roots > flowers, stems and fruits > leaves. The genes of FPS and β-AS were expressed predominantly in flowers and roots, respectively. This study may provide a suitable internal control for quantitative
gene expression assays in various tissues and give insight into the tissue expression profiles of four saikosaponins biosynthesis-involved
genes of medicinal B. chinense. 相似文献
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We have characterized the promoter specificity of theArabidopsis thaliana α1-tubulin (α
1-tub) gene by studying expression patterns of gene fusions between the 2.2 kbp 5′ upstream region of theα
1-tub gene and each of three different reporters: chloramphenical acetyltransferase, β-glucuronidase or the diphtheria toxin chain
A gene. Analysis of transgenic tobacco andArabidopsis plants carrying the transgene showed that the chloramphenicol acetyltransferase and β-glucuronidase activities were not detected
in any vegetative or reproductive organs except mature pollen. Transgenic tobacco plants carrying the diphtheria toxin chain
A gene under the control of theα
1-tub promoter were of normal phenotype but seed fertility was drastically reduced. Furthermore, the transgene could not be transmitted
to the next generation through pollen, supporting the observation that theα
1-tub promoter is active only in pollen. It was observed that the promoter activity was most active in mature pollen and decreased
significantly duringin vitro pollen germination, indicating that the promoter is inactive or subdued in germinating pollen. The promoter activity was
not affected by various plant growth hormones during pollen maturation. 相似文献
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Seven analogues of p-nitrophenyl T-antigen [Galβ(1→3)GalNAcα(1→O)PNP] have been synthesized as potential substrates for elucidation of the substrate specificity of endo-α-N-acetylgalactosaminidase. These compounds, which are commercially unavailable, include: GlcNAcβ(1→3){GlcNAcβ(1→6)}GalNAcα(1→O)PNP [core 4 type], GalNAcα(1→3)GalNAcα(1→O)PNP [core 5 type], GlcNAcβ(1→6)GalNAcα(1→O)PNP [core 6 type], GalNAcα(1→6)GalNAcα(1→O)PNP [core 7 type], Galα(1→3)GalNAcα(1→O)PNP [core 8 type], Glcβ(1→3)GalNAcα(1→O)PNP and GalNAcβ(1→3)GalNAcα(1→O)PNP. The assembly of these synthetic probes was accomplished efficiently, based on di-tert-butylsilylene(DTBS)-directed α-galactosylation as a key reaction. 相似文献
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Marie-Aleth Lacaille-Dubois Dieudonné Emmanuel Pegnyemb Olivier Placide Noté Anne-Claire Mitaine-Offer 《Phytochemistry Reviews》2011,10(4):565-584
The aim of this review is to highlight updated results on the biologically active saponins from Leguminosae-Mimosoideae. Acacic
acid-type saponins (AATS), is a class of very complex glycosides possessing a common aglycon unit of the oleanane-type (acacic
acid = 3β, 16α, 21β trihydroxy-olean-12-en-28 oic acid), having various oligosaccharide moieties at C-3 and C-28 and an acyl
group at C-21. About sixty molecules of this type have been actively explored in recent years from Leguminosae family, from
a chemical point of view and some fifty were reported to possess cancer related activities. These include cytotoxic/antitumor,
immunomodulatory, antimutagenic, and apoptosis inducing properties and appear to depend on the acylation and esterification
by different moieties at C-21 and C-28 of the acacic acid-type aglycone. One can observe that the (6S) configuration of the outer monoterpenyl moiety (MT) seems more potent in mediating high cytotoxicity than its (6R) isomer. Furthermore, the trisaccharide moiety {β-d-Xylopyranosyl-(1→2)-β-d-Fucopyranosyl-(1→6)- N-Acetamido 2-β-d-Glucopyranosyl-} at C-3, the tetrasaccharide moiety {β-d-Glucopyranosyl-(1→3)-[α-L-Arabinofuranosyl-(1→4)]-α-l-Rhamnopyranosyl-(1→2)-β-d-Glucopyranosyl} at C-28 of the aglycone, and the inner MT hydroxylated at its C-9, having a (6S) configuration can be important substituent patterns for the induction of apoptosis of AATS. Because of their interesting
cytotoxic/apoptosis inducing activity, some AATS can be useful in the search for new potential antitumor agents from Fabaceae.
Furthermore, the sequence 28-O-{Glc-(1→3)-[Araf-(1→4)]-Rha-(1→2)-Glc-Acacic acid}, often encountered in the genera Acacia, Albizia, Archidendron, and Pithecellobium may represent a chemotaxonomic marker of the Mimosoideae subfamily. 相似文献
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McManus S Chamoux E Bisson M Roux S 《Apoptosis : an international journal on programmed cell death》2012,17(2):121-131
TRAIL (TNF-related apoptosis-inducing ligand) has been shown to induce apoptosis by binding to TRAIL-R1 and -R2 death receptors,
but not to TRAIL-R3 or -R4, its decoy receptors that lack the internal death domain. Osteoclasts (Ocs) are sensitive to TRAIL-induced
apoptosis, and modulation of these receptors may change Oc sensitivity to TRAIL. Using human Oc cultures, we first investigated
the gene expression profile of these receptors (TNFRSF10 -A, -B, -C, -D encoding TRAIL-Rs 1–4) by real time PCR after adding osteotropic factors during the last week of Oc cultures. We observed
a significant decrease in the expression of TNFRSF10-A after the addition of TGFβ, and an increase in that of TNFRSF10-A and -B post-PTH stimulation. Protein expression of TRAIL-R1 and -R3 was upregulated in the presence of MIP-1α, but down-regulated
in the presence of TGFβ (R1), TRAIL (R2) or OPG (R3). The percentage of Ocs expressing the TRAIL-R1 and/or -R2 at their surface
was increased by MIP-1α and TRAIL, increased (R2) or decreased (R1) by TGFβ, and the percentage expressing TRAIL-R3 was increased
by MIP-1α, TRAIL and RANKL. Although significant, the magnitude of all these changes was of about 10–15%. While a direct correlation
between these changes and TRAIL-induced Oc apoptosis was less clear, a protective effect was observed in Ocs that had been
treated with OPG, and an additive effect in Ocs pre-treated with TRAIL or TGFβ increased TRAIL sensitivity. 相似文献
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NOEs between the β-protons of cysteine residues across disulfide bonds in proteins provide direct information on the connectivities
and conformations of these important cross-links, which are otherwise difficult to investigate. With conventional [U-13C, 15N]-proteins, however, fast spin diffusion processes mediated by strong dipolar interactions between geminal β-protons prohibit the quantitative measurements and thus the analyses of long-range NOEs across disulfide bonds. We describe
a robust approach for alleviating such difficulties, by using proteins selectively labeled with an equimolar mixture of (2R, 3S)-[β-13C; α,β-2H2] Cys and (2R, 3R)-[β-13C; α,β-2H2] Cys, but otherwise fully deuterated. Since either one of the prochiral methylene protons, namely β2 (proS) or β3 (proR), is always replaced with a deuteron and no other protons remain in proteins prepared by this labeling scheme, all four of
the expected NOEs for the β-protons across disulfide bonds could be measured without any spin diffusion interference, even
with long mixing times. Therefore, the NOEs for the β2 and β3 pairs across each of the disulfide bonds could be observed at
high sensitivity, even though they are 25% of the theoretical maximum for each pair. With the NOE information, the disulfide
bond connectivities can be unambiguously established for proteins with multiple disulfide bonds. In addition, the conformations
around disulfide bonds, namely χ2 and χ3, can be determined based on the precise proton distances of the four β-proton pairs, by quantitative measurements of the
NOEs across the disulfide bonds. The feasibility of this method is demonstrated for bovine pancreatic trypsin inhibitor, which
has three disulfide bonds. 相似文献
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P2X1 receptors, the major subtype of P2X receptors in the vascular smooth muscle, are essential for α,β-methylene adenosine 5′-triphosphate
(α,β-MeATP)-induced vasoconstriction. However, relative physiological significance of P2X1 receptor-regulated vasoconstriction in the different types of arteries in the rat is not clear as compared with α1-adrenoceptor-regulated vasoconstriction. In the present study, we found that vasoconstrictive responses to noncumulative
administration of α,β-MeATP in the rat isolated mesenteric arteries were significantly smaller than those to single concentration
administration of α,β-MeATP. Therefore, we firstly reported the characteristic of α,β-MeATP-regulated vasoconstrictions in
rat tail, internal carotid, pulmonary, mesenteric arteries, and aorta using single concentration administration of α,β-MeATP.
The rank order of maximal vasoconstrictions for α,β-MeATP (E
max·α,β-MeATP) was the same as that of maximal vasoconstrictions for noradrenaline (E
max·NA) in the internal carotid, pulmonary, mesenteric arteries, and aorta. Moreover, the value of (E
max·α,β-MeATP/E
max·KCl)/(E
max·NA/E
max·KCl) was 0.4 in each of the four arteries, but it was 0.8 in the tail artery. In conclusion, P2X1 receptor-mediated vasoconstrictions are equally important in rat internal carotid, pulmonary, mesenteric arteries, and aorta,
but much greater in the tail artery, suggesting its special role in physiological function. 相似文献
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Nellie Y. Loh Helen J. Ambrose Lisa M. Guay-Woodford Srimita DasGupta Ralph A. Nawrotzki Derek J. Blake Kay E. Davies 《Mammalian genome》1998,9(11):857-862
β-Dystrobrevin, a dystrophin-related protein that is expressed in non-muscle tissues, is highly homologous to α-dystrobrevin,
a member of the dystrophin-associated protein complex (DPC). β-Dystrobrevin associates with Dp71 and syntrophin and is believed
to have a role in non-muscle DPCs. Here we report the characterization and mapping of the mouse β-dystrobrevin gene. The mouse
β-dystrobrevin gene is organized into 21 exons spanning over 130 kb of DNA. We provide evidence that this gene is transcribed
from at least two promoter regions but appears to utilize a common translation initiation site. We show that the similarity
between β-dystrobrevin and α-dystrobrevin is reflected in the conservation of their exon-intron junctions. β-Dystrobrevin
has been localized to proximal mouse Chromosome (Chr) 12 by backcross mapping. A database search revealed that two mouse genetic
diseases involving tissues expressing β-dystrobrevin have been mapped to this region, namely, congenital polycystic kidneys
(cpk) and fatty liver dystrophy (fld). However, refined mapping analysis has excluded β-dystrobrevin as a candidate gene for either disease.
Received: 1 June 1998 / Accepted: 16 July 1998 相似文献