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1.
The X chromosomally located allele Sgs-4
c
for a larval secretion protein of Drosophila melanogaster is normally expressed in female larvae of the strain Oregon R and is hyperexpressed in male larvae exhibiting dosage compensation; the allele Sgs-4
d
in the strain Samarkand is weakly expressed and is not hyperexpressed in male larvae showing a dosage effect. P element-mediated transformation of upstream DNA sequences from both alleles combined with Sgs-4
d
coding and downstream sequences was performed to localize sequences which are responsible for the level of gene expression and for hyperexpression of Sgs-4
c
in male larvae. Our results demonstrate that weak expression and dosage effect are inherited with the upstream region from –1 to –838. This Samarkand fragment differs from the homologous Oregon R region only by a C to T transiion at –344 which lies within an assumed binding sequence for the ecdysone receptor complex of dyad base symmetry. Replacing the Samarkand upstream region from –1 to –838 by the Oregon R region restores normal Sgs-4 expression and dosage compensation. Hyperexpression in male larvae displays high sensitivity to position effect and is nearly completely inhibited in one transformed line under heterozygous conditions. The integration of an Sgs-4
d
transposon into a weak spot of polytene chromosome 2L results in a decrease in gene expression. The GTT- and GT-rich regions at –1.2 and –2.0 kb do not obviously influence Sgs-4 expression but possibly play a role in induction of stage-specific chromosome puffing. 相似文献
2.
Peter D'Eustachio Shirin Jadidi Robert C. Fuhlbrigge Patrick W. Gray David D. Chaplin M.D. Ph.D. 《Immunogenetics》1987,26(6):339-343
Two interleukin-1 polypeptides, and , are known, and cDNAs corresponding to each have been described. Genomic cloning and Southern blotting experiments suggest that in the mouse each is encoded by a gene present in one copy per haploid genome. Analysis of a panel of somatic cell hybrids carrying various mouse chromosomes on a constant Chinese hamster background indicates that both genes map to mouse chromosome 2. Further, analysis of the inheritance of DNA restriction fragment length polymorphisms associated with each gene in recombinant inbred strains of mice shows the two loci to be tightly linked to one another, and to lie approximately 4.7 centimorgans distal to B2m (beta-2 microglobulin). We have named the locus encoding IL-1
Il-1 and the locus encoding IL-1
Il-1b. 相似文献
3.
4.
The cellular amounts and cellular activities of acetyl CoA carboxylase (ACC; EC 6.4.1.2.) were determined in the first leaves of diploid, tetraploid and hexaploid species of Triticum (wheat). Per leaf the ACC activities were very similar in T. monococcum (2 ), T. dicoccum (4 ) and T. aestivum (6 ). The ACC activity per chloroplast also showed little variation between species of different ploidy but since chloroplast number increases with ploidy, the ACC activities and ACC amounts per cell also increased with ploidy. These cellular increases in ACC amounts associated with increases in gene dosage were highly co-ordinated in the diploids T. monococcum and T. tauschii and their respective autotetraploids so the specific activity of ACC was highly conserved in these plants. The relevance of these findings to attempts to genetically manipulate lipid biosynthesis in chloroplasts is discussed.Abbreviation ACC
acetyl CoA carboxylase
We are very grateful to Dr. Kevin Pyke and Miss Jo Marrison for many helpful discussions and to Dr. Collin Law for the generous gift of seeds. 相似文献
5.
Li C. -D. Langridge P. Lance R. C. M. Xu P. Fincher G. B. 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(7):791-796
Members of the (13)--glucan glucanohydrolase (EC 3.2.1.39) gene family have been mapped on the barley genome using three doubled haploid populations and seven wheat-barley addition lines. Specific probes or polymerase chain reaction (PCR) primers were generated for the seven barley (13)--glucanase genes for which cDNA or genomic clones are currently available. The seven genes are all located on the long arm of chromosome 3 (3HL), and genes encoding isoenzymes GI, GII, GIII, GIV, GV and GVII (ABG2) are clustered in a region less than 20 cM in length. The region is flanked by the RFLP marker MWG2099 on the proximal side and the Barley Yellow Mosaic Virus (BYMV) resistance gene ym4 at the distal end. The gene encoding isoenzyme GVI lies approximately 50 cM outside this cluster, towards the centromere. With the exception of the gene encoding isoenzyme GIV, all of the (13)--glucanase genes are represented by single copies on the barley genome. The probe for the isoenzyme GIV gene hybridized with four DNA bands during Southern blot analysis, only one of which could be incorporated into the consensus linkage map. 相似文献
6.
E. Leberer T. Leeuw D. Harcus D. Y. Thomas J. Chenevert I. Herskowitz 《Molecular & general genetics : MGG》1996,252(5):608-621
The pheromone signal in the yeastSaccharomyces cerevisiae is transmitted by the and subunits of the mating response G-protein. TheSTE20 gene, encoding a protein kinase required for pheromone signal transduction, has recently been identified in a genetic screen for high-gene-dosage suppressors of a partly defective G mutation. The same genetic screen identifiedBEM1, which encodes an SH3 domain protein required for polarized morphogenesis in response to pheromone, and a novel gene, designatedMDG1 (multicopy suppressor ofdefectiveG-protein). TheMDG1 gene was independently isolated in a search for multicopy suppressors of abem1 mutation. TheMDG1 gene encodes a predicted hydrophilic protein of 364 amino acids with a molecular weight of 41 kDa that has no homology with known proteins. A fusion of Mdg1p with the green fluorescent protein fromAequorea victoria localizes to the plasma membrane, suggesting that Mdg1p is an extrinsically bound membrane protein. Deletion ofMDG1 causes sterility in cells in which the wild-type G has been replaced by partly defective G derivatives but does not cause any other obvious phenotypes. The mating defect of cells deleted forSTE20 is partially suppressed by multiple copies ofBEM1 andCDC42, which encodes a small GTP-binding protein that binds to Ste20p and is necessary for the development of cell polarity. Elevated levels ofSTE20 andBEM1 are capable of suppressing a temperature-sensitive mutation inCDC42. This complex network of genetic interactions points to a role for Bem1p and Mdg1p in G-protein mediated signal transduction and indicates a functional linkage between components of the pheromone signalling pathway and regulators of cell polarity during yeast mating. 相似文献
7.
The signaling mechanisms for most of the antiproliferative processes are not fully understood. We have demonstrated that ERK(MAPK) signaling was involved in the induction of both p15INK4band p16INK4a CDK inhibitors and growth inhibition of hepatoma cell HepG2 triggered by the tumor promoter tetradecanoyl phorbol acetate (TPA). In this study, the upstream signal mechanism for TPA-induced ERK(MAPK) activation was investigated. In HepG2 cells only one of the cPKC isozymes, PKC, but not cPKCII, nPKC or aPKC was activated by TPA as demonstrated by its membrane translocation within 10–30 min and down-regulation at 24 h after TPA treatment. Pretreatment of 0.2–2.0 M Bisindolylmaleimides, an inhibitor of PKC, attenuated the TPA-induced phosphorylation of ERK, gene expressions of p15INK4band p16INK4a, and growth inhibition of HepG2 cell in a dose-dependent manner. Consistently, transfection of HepG2 with 1.0–3.0 M antisense (AS) PKC, but not (AS) PKCII, or nPKC oligonucleotides (ODN), for 36 h prior to TPA treatment also prevented the TPA-induced molecular and cellular effects described above. Taken together, we concluded that PKC is specifically required for TPA-induced ERK(MAPK) signaling to trigger gene expressions of p15INK4band p16INK4a leading to HepG2 growth inhibition. 相似文献
8.
9.
Teye K Quaye IK Koda Y Soejima M Pang H Tsuneoka M Amoah AG Adjei A Kimura H 《Human genetics》2004,114(5):499-502
We have identified a novel base substitution at codon 247 in the -chain of the haptoglobin 2 (Hp2) allele in a Ghanaian with the Hp0 (ahaptoglobinemic) phenotype. The heterozygous TC substitution caused reduced expression of the protein when the mutant was transfected into COS7 cells. The base substitution resulted in a missense change of the non-polar amino acid isoleucine to the polar amino acid threonine at a position in the -chain that is highly conserved among several species. We had previously identified a mutation in the Hp gene promoter region for the same individual, which gives her genotype as –61CHp2/–61CHp2(I247T). Since the –61C mutation also leads to low Hp expression, the genotype represents the first and most definitive ahaptoglobinemic case reported in Africa. 相似文献
10.
Summary The nucleotide sequences of the rrnB 16S ribosomal RNA gene and its 5-and 3-flanking regions from Mycoplasma capricolum have been determined. The coding sequence is 1521 base pairs long, being 21 base pairs shorter than that of the Scherichia coli 16S rRNA gene. The 16S rRNA sequence of M. capricolum reveals 74% and 76% identity with that of E. coli and Anacystis nidulans, respectively. The secondary structure model constructed from the M. capricolum 16S rRNA.gene sequence resembles that proposed for E. coli 16S rRNA. A large stem structure can be constructed between the 5- and 3-flanking sequences of the 16S rRNA gene. The flanking regions are extremely rich in AT. 相似文献
11.
Elinor J. McCrone Phillip G. Sokolove 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1979,133(2):117-123
Summary Physiological and endocrine mechanisms mediating long-day (LD 168) triggered sexual maturation were studied in the terrestrial slug,Limax maximus. Our findings were: (1) Maturation was induced in immature slugs seeing only short days (LD 816) after implantation of whole brains from maturing donors, but no development was found in sham-operated control slugs or in animals receiving implants of muscle from mature donors (Table 1). (2) Removal of the optic tentacles did not block maturation in LD 168 or promote maturation in LD 816 (Fig. 1). (3) Gonadectomy (castration) abolished penis development in 9 of 11 slugs exposed to LD 168 for periods of up to 31 weeks (Table 2). The results are consistent with a model forLimax reproductive tract development in which the perception of long days by extraocular receptors results in the secretion of a maturation hormone by the brain followed by the production of a separate male-phase sex hormone by the developing gonad.Abbreviations
ASO
accessory sex organs
-
DB
dorsal bodies
-
FPSH
female-phase sex hormone
-
MH
maturation hormone
-
MPSH
male-phase sex hormone
This work was supported in part by grants from NSF (BNS 78-01408) and NIH (MH 27948) to P.G.S. The assistance of Mr. T.M. Gordon, Mr. J.L. Broyles, and Mr. M. Bullock is gratefully acknowledged. 相似文献
12.
Jan B L Damm Hans Voshol Karl Hård Johannis P Kamerling Gijs W K Van Dedem Johannes F G Vliegenthart 《Glycoconjugate journal》1988,5(3):221-233
TheN-linked carbohydrate chains of the-subunit of highly purified urinary human chorionic gonadotropin have been re-investigated. The oligosaccharides were released enzymatically by peptide-N
4-(N-acetyl--glucosaminyl)asparagine amidase-F, and fractionated by a combination of FPLC and HPLC. As a result of the application of improved fractionation methods, apart from the earlier reported carbohydrate chains, also small amounts of trisialo tri- and tri-antennary oligosaccharides were found. The primary structures of the latter carbohydrate chains have been determined by 500-MHz1H-NMR spectroscopy to beAbbreviations hCG
human chorionic gonadotropin
- hCG-
-subunit
- hCG-
-subunit
- PNGase-F
peptide-N
4-(N-acetyl--glucosaminyl)asparagine amidase-F (E.C. 3.5.1.52)
- endo-F
endo--N-acetylglucosaminidase-F (E.C. 3.2.1.96)
- SDS
sodium dodecyl sulphate
- PAGE
polyacrylamide gel electrophoresis
- CBB
coomassie brilliant blue R 250
- GlcNAc
N-acetylglucosamine
- NeuAc
N-acetylneuraminic acid
- Man
mannose
- Gal
galactose
- Fuc
fucose 相似文献
13.
14.
Seventeen linking clones sublocalized to the central region of the mouse X Chromosome (Chr) were screened against genomic DNA from male mice carrying the tabby-25H (Ta
25H
) deletion. Two of these linking clones, EM131 and EM169, were found to be deleted in Ta
25H
/Y animals. Genetic mapping through Mus musculus domesticus/Mus spretus interspecific backcross progeny, segregating for the original tabby (Ta) gene mutation, was utilized to order these markers and to define nearest flanking markers to the Ta
25H
deletion (EM140 and EM171). The size of the Ta
25H
deletion was thus estimated as up to 4.5 centiMorgans (cM). The order of markers, proximal to distal, was found to be EM140/EM131, mouse androgen receptor gene (Ar)/EM169, Ta/EM171. A putative CpG-rich island and a highly evolutionarily conserved DNA probe were isolated from the DXCrc169 locus which co-segregates with the Ta locus in this study. 相似文献
15.
TheDrosophila nuclear proteins Bj6 and Bx42 characterized previously are detected in a series of developmentally active puffs on salivary gland chromosomes. Here the binding of both proteins at puff 3C11-12 containing the glue protein geneSgs-4 is described in more detail. By deletion analysis we show that both proteins bind within a chromosomal segment containing 17–19 kb of DNA surrounding theSgs-4 gene. They are detectable at this site during the intermoult stages, before the puff regresses in response to the moulting hormone ecdysone. If theSgs-4 gene together with flanking DNA sequences is brought into a different chromosomal position by P element transfer, both proteins are detected at this new location. Both proteins are bound to the chromosome within the range of 2.5 kb DNA upstream of theSgs-4 gene. A strain containing a 52 bp deletion within this region fails to bind Bx42 protein suggesting that the missing DNA, which overlaps a hypersensitive region, may be required for the binding of the Bx42 protein. 相似文献
16.
The TROSY principle has been introduced into a HNCA experiment, which is designed for measurements of the intraresidual and sequential H-C/HN-N dipole/dipole and H-C/N dipole/CSA cross-correlated relaxation rates. In addition, the new experiment provides values of the 3,4
J
H HN coupling constants measured in an E.COSY manner. The conformational restraints for the and angles are obtained through the use of the cross-correlated relaxation rates together with the Karplus-type dependencies of the coupling constants. Improved signal-to-noise is achieved through preservation of all coherence transfer pathways and application of the TROSY principle. The application of the [15N,13C]-DQ/ZQ-[15N,1H]-TROSY-E.COSY experiment to the 16 kDa apo-form of the E. coli Heme Chaperon protein CcmE is described. Overall good agreement is achieved between and angles measured with the new experiment and the average values determined from an ensemble of 20 NMR conformers. 相似文献
17.
R. Gossrau 《Histochemistry and cell biology》1977,51(2-3):219-237
Zusammenfassung Nach Ermittlung verschiedener Reaktionskonstanten resultiert folgender Ansatz zur photometrischen Bestimmung der sauren-Galactosidase (Messung des Azoindoxylfarbstoffs bei 540 nm nach Extraktion mit Dimethylformamid oder-acetamid): 1,5 mM 5-Br-4-Cl-3-Indolyl--d-galactosid (1 mg gelöst in 0,05 ml Dimethylformamid) und 0,01–0,015 ml Hexazonium-p-rosanilin/ml in 0,1 M Citronensäure-Phosphat-Puffer, pH 4. Die damit untersuchten Rattenorgane besitzen unterschiedliche Aktivitäten an saurer-Galactosidase; NaCl läßt die Enzymaktivität unbeeinflußt. — ähnliche Resultate liefert das Indigogen-Verfahren; Indigo kann wie der Azoindoxylfarbstoff gelöst und gemessen werden.Hexazotiertes p-Rosanilin in höheren Konzentrationen hemmt die saure-Galactosidase zu etwa 50%; niedrige sowie Ferricyanid-Ferrocyanid inhibieren nicht. Die Hemmwirkung von Glutar- und Formaldehyd läßt sich mit dem Azoindoxylverfahren nicht messen, da der Farbstoff unvollständig aus fixiertem Material extrahiert wird.Auf Grund der biochemischen Befunde ergibt sich nachstehendes histochemisches Medium zur Darstellung der sauren-Galactosidase: 7,5 (1,5 mM) 5-Br-4-Cl-3-Indolyl--d-galactosid (gelöst in 0,25 ml Dimethylformamid) und 0,05–0,15 ml Hexazonium-p-rosanilin in 10 ml 0,1 M Citronensäure-Phosphat-Puffer, pH 4. Nach der Inkubation können die Schnitte osmiert, dehydriert und in Kunstharz oder ohne Osmierung in Glycerin-Gelatine eingedeckt werden. Das Osmiumchelat ist in organischen Solventien unlöslich; seine Stabilität hängt von der Hexazonium-p-rosanilin-Konzentration ab.Mit dieser Methode läßt sich die saure-Galactosidase nach Fixation in Glutaraldehyd oder einem Glutaraldehyd-Formaldehyd-Gemisch exakt in den Lysosomen zahlreicher Rattenorgane erfassen.Verglichen mit dem Indigogen- und Metallsalzverfahren und den simultanen Azokupplungsreaktionen zum histochemischen Nachweis der sauren-Galactosidase ist die Azoindoxyltechnik überlegen oder gleichwertig; der biochemische Ansatz leistet Nützliches für kombinierte quantitativ-qualitative Studien des Enzyms.
Azoindoxyl methods for the investigation of hydrolases
Summary The determination of various reaction constants yields the following assay for the photometric evaluation of acid-galactosidase (measurement of the azoindoxyl dye at 540 nm after extraction with dimethylformamide or-acetamide): 1.5 mM 5-Br-4-Cl-3-indolyl--d-galactoside (1 mg dissolved in 0.05 ml dimethylformamide) and 0.01–0.015 ml hexazotized p-rosaniline/ml in 0.1 M citric acid-phosphate buffer, pH 4. By means of this procedure it becomes evident that the activity of the enzyme differs considerably in various rat organs; NaCl does not influence acid-galactosidase. — Similar results were obtained with the indigogenic method; indigo can be dissolved and measured photometrically as the azoindoxyl dye.The enzyme is suppressed by high concentrations of hexazotized p-rosaniline to 50%; low concentrations do not inhibit; the same is true for ferricyanide-ferrocyanide employed in the indigogenic media. — The effect of glutar-and formaldehyde on acid-galactosidase cannot be investigated with the azoindoxyl reaction since the azoindoxyl dye partially withstands extraction from fixed blocks of tissue.On the basis of the biochemical findings the azoindoxyl technique can be recommended for the histochemical demonstration of acid-galactosidase: 7.5 mg (1.5 mM) 5-Br-4-Cl-3-indolyl--d-galactoside (dissolved in 0.25 ml dimethylformamide) and 0.05–0.15 ml hexazonium-p-rosaniline in 10 ml 0.1 M citric acid-phosphate buffer, pH 4. After incubation the sections can be treated with osmium tetroxide followed by dehydration and mounting in resins or can be mounted without prior osmification of the azoindoxyl dye in glycerin jelly. The osmium chelate resists treatment with organic solvents; the stability of the chelate depends on the concentration of hexazotized p-rosaniline.After fixation in glutaraldehyde or in a mixture of form- and glutaraldehyde acid-galactosidase can be exactly localized in the lysosomes of many rat organs.In comparison with the indigogenic, the metal precipitation and the simultaneous azocoupling reactions for the in situ detection of acid-galactosidase the azoindoxyl procedure is superior if fixed material is used; it is equivalent or inferior in connection with the membrane technique. The biochemical azoindoxyl assay represents a useful method for combined qualitative and quantitative studies of acid-galactosidase.相似文献
18.
We have analyzed the organization and the structure of rabbit chain genes encoding b allotypes in wild rabbits. The 1 gene of the b95 allotype was cloned and its structure determined. The J region is composed of five segments but only J2 appears to be functional and is identical to the J2 segment of the b4 allotype. The J region is highly conserved among the various b allotypes, whereas the constant region exon displays a high level of differences when compared with other allotypes (9%–30% of different amino acids). The b95 J region is closer to that of b4var and the constant region to b5 allotype constant region. Alignment of nucleotide sequences revealed that the constant region exon displays segmental similarities with b4 and bas constant regions. The mosaic structure of b95 allotype gene indicates that complex allotypes of 1 genes may result from genetic exchanges of gene conversion between the different genes.The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide database and have been assigned the accession number M22542.
Address correspondence and offprint requests to: P.-A. Cazenave. 相似文献
19.
J. Kojima 《Insectes Sociaux》1996,43(4):411-420
Summary Colonies of an Australian swarm founding polistine wasp,Ropalidia romandi, on the Atherton Tableland, Queensland, manage perennial nests by practicing seasonal colony activity. In summer nests, most cells were occupied by immatures of all developmental stages. The proportion of cells that did not contain immatures increased towards winter, when most nest cells did not contain immatures and half of these winter nests had rather large amounts of nectar deposited in empty cells. While the visits to tree flowers byR. romandi were not frequent in summer, nearly 60 % of insects collected on tree flowers in winter wereR. romandi. With such seasonal switching in the modes of colony reproductive activity and of nectar foraging behavior,R. romandi responds to its physical and biotic environment. In this way,R. romandi may be able to continue colonies throughout the year, with much reduced level of colony activity in winter, in areas with seasons that are unfavorable for reproductive activity of a colony. 相似文献
20.
A novel triple-resonance NMR method is presented for the measurement of the protein backbone dihedral angle based on differential multiple-quantum relaxation induced by relaxation interference between 1H(i)-13C(i) dipolar and 13C(i–1) (carbonyl) chemical shift anisotropy mechanisms. The method employs a simultaneous transfer of 15N magnetization to the inter- and intra-residue 13C carbons as well as the directly attached carbonyl carbon 13C. Results obtained on 13C,15N-labeled ubiquitin demonstrate the potential of the method. 相似文献