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111.
A G DiLella A Hawkins R J Craig S L Schreiber C A Griffin 《Biochemical and biophysical research communications》1992,189(2):819-823
Human FKBP12 and FKBP13 are encoded by distinct genes designated FKBP1 and FKBP2, respectively. Human FKBP1 was previously characterized. The characterization of human FKBP2 is described. FKBP2 is three kb in length and contains six exons. Fluorescence in situ hybridization of FKBP1 and FKBP2 genomic probes to metaphase chromosomes localized FKBP1 to human chromosome 20 band p13 and FKBP2 to human chromosome 11 band q13.1-q13.3. 相似文献
112.
113.
Long-term treatment of isolated rat soleus muscle with phorbol ester leads to loss of contraction-induced glucose transport. 总被引:2,自引:0,他引:2 下载免费PDF全文
Muscle contraction involves mobilization of intracellular Ca2+ and is associated with several metabolic adjustments, including increased glucose transport. In the present study isolated rat soleus muscles were exposed to 12-O-tetradecanoylphorbol 13-acetate, and responses to both insulin and contraction in terms of glucose transport were assessed. Muscles treated with this phorbol ester for 12 h showed an increased basal rate of 3-O-methylglucose uptake, and responded partially to insulin but did not respond to contraction. Phorbol-ester-treated and non-treated (vehicle-only) muscles were indistinguishable in terms of pre-contraction content of adenine nucleotide, phosphocreatine, lactate and glycogen, as well as contractile performance and contraction-induced glycogenolysis. Phorbol ester treatment of isolated solei for 12 h resulted in the loss of 90% of protein kinase C activity as determined with histone IIIs as substrate, and 70% as determined by using phorbol ester binding. It is concluded that treatment of solei with phorbol ester gives rise to a marked loss of contraction-induced glucose transport. 相似文献
114.
Nonlegume hemoglobin genes retain organ-specific expression in heterologous transgenic plants. 总被引:3,自引:1,他引:2 下载免费PDF全文
Hemoglobin genes from the nitrogen-fixing nonlegume Parasponia andersonii and the related non-nitrogen-fixing nonlegume Trema tomentosa have been isolated [Landsmann et al. (1986). Nature 324, 166-168; Bogusz et al. (1988). Nature 331, 178-180]. The promoters of these genes have been linked to a beta-glucuronidase reporter gene and introduced into both the nonlegume Nicotiana tabacum and the legume Lotus corniculatus. Both promoters directed root-specific expression in transgenic tobacco. When transgenic Lotus plants were nodulated by Rhizobium loti, both promoter constructs showed a high level of nodule-specific expression confined to the central bacteroid-containing portion of the nodule corresponding to the expression seen for the endogenous Lotus leghemoglobin gene. The T. tomentosa promoter was also expressed at a low level in the vascular tissue of the Lotus roots. The hemoglobin promoters from both nonlegumes, including the non-nodulating species, must contain conserved cis-acting DNA signals that are responsible for nodule-specific expression in legumes. We have identified sequence motifs postulated previously as the nodule-specific regulatory elements of the soybean leghemoglobin genes [Stougaard et al. (1987). EMBO J. 6, 3565-3569]. 相似文献
115.
X J Guo A F Chambers C L Parfett P Waterhouse L C Murphy R E Reid A M Craig D R Edwards D T Denhardt 《Cell growth & differentiation》1990,1(7):333-338
A mouse mRNA, provisionally designated 5B10, has been cloned based on its inducibility by serum in quiescent murine fibroblasts. Here we report the full-length complementary DNA sequence and a partial characterization. There are about five copies of the gene in the mouse genome. Sequence analysis of the 5B10 coding region reveals 94 and 97% amino acid identity to human and rat calcyclin, respectively. Although the coding region has been highly conserved during evolution of the rodent and human genomes, the untranslated flanking sequences differ significantly. A protein of Mr about 8000 was produced by in vitro translation of the mRNA transcribed in vitro from 5B10 complementary DNA in a riboprobe vector. An antiserum raised against a portion of the predicted human calcyclin protein cross-reacted with this mouse protein. 5B10 mRNA was found in greatest amount in organs containing proliferating cells, e.g., epidermis, skin, stomach, uterus of pregnant mouse, placenta, and decidua. Brain, liver, mature thymus, and skeletal muscle had little or no detectable 5B10 mRNA. 5B10 mRNA levels were higher in cells treated with 7,12-dimethylbenzanthracene and 12-O-tetradecanoylphorbol-13-acetate than in their normal counterparts, suggesting a role in tumorigenesis. In addition, high 5B10 mRNA levels were associated with metastatic ability in a series of ras-transformed cells, in proportion to levels of ras p21 expressed by the cells, implicating 5B10 even more deeply in carcinogenesis. 相似文献
116.
Tn7 transposition as a probe of cis interactions between widely separated (190 kilobases apart) DNA sites in the Escherichia coli chromosome. 总被引:3,自引:0,他引:3 下载免费PDF全文
We have used the bacterial transposon Tn7 to examine communication between widely separated DNA sites in the Escherichia coli chromosome. Using Tn7 target immunity, a regulatory feature of transposition which influences target selection, we have evaluated (i) how the presence of Tn7 sequences at one DNA site affects Tn7 insertion into another site in the same DNA molecule and (ii) the nucleotide distances over which the two sites are able to communicate. We demonstrate that Tn7 sequences at one chromosomal site act at a distance to inhibit insertion of Tn7 elsewhere in that DNA as far away as 190 kb, reflecting effective long-range cis interactions. We have found that while target immunity is effective over a substantial region of the chromosome, insertion of Tn7 into a more distant site 1.9 Mb away in the same DNA is not inhibited; this observation provides evidence that target immunity relies on DNA spacing. We also find that within the region of the chromosome affected by target immunity, the magnitude of the immune effect is greater at close DNA sites than DNA sites farther away, suggesting that target immunity is distance dependent. We also extend the characterization of the Tn7 end-sequences involved in transposition and target immunity and describe how Tn7 target immunity can be used as a tool for probing bacterial chromosome structure. 相似文献
117.
Cloning of a cryV-type insecticidal protein gene from Bacillus thuringiensis: the cryV-encoded protein is expressed early in stationary phase. 总被引:5,自引:0,他引:5 下载免费PDF全文
K Kostichka G W Warren M Mullins A D Mullins N V Palekar J A Craig M G Koziel J J Estruch 《Journal of bacteriology》1996,178(7):2141-2144
A CryV-type protein (CGCryV) has been isolated from supernatant fluids of Bacillus thuringiensis AB88 cultures. Previous reports have suggested the cryptic nature of the cryV-type genes on the basis of the absence of CryV-type proteins in parasporal crystals. The CryV-type protein reported here is expressed early in stationary phase, and evidence indicates that it is an exported protein. Analysis of the deduced protein sequence from this gene reveals the presence of an N-terminal domain that likely acts as a signal peptide. The CGCryV protein is the first reported case of a delta-endotoxin being a secreted protein, which may influence the biological relevance of these proteins. 相似文献
118.
The productivity of ethanol fermentation processes, predominantly based on batch operation in the U.S. fuel ethanol industry, could be improved by adoption of continuous processing technology. In this study, a conventional yeast fermentation was coupled to a flat-plate membrane pervaporation unit to recover continuously an enriched ethanol stream from the fermentation broth. The process employed a concentrated dextrose feed stream controlled by the flow rate of permeate from the pervaporation unit via liquid-level control in the fermentor. The pervaporation module contained 0.1 m2 commercially available polydimethylsiloxane membrane and consistently produced a permeate of 20%–23% (w/w) ethanol while maintaining a level of 4%–6% ethanol in a stirred-tank fermentor. The system exhibited excellent operational stability. During continuous operation with cell densities of 15–23 g/l, ethanol productivities of 4.9–7.8 gl–1 h–1 were achieved utilizing feed streams of 269–619 g/l glucose. Pervaporation flux and ethanol selectivities were 0.31–0.79 lm–2 h–1 and 1.8–6.5 respectively. 相似文献
119.
Arabidopsis consensus intron sequences 总被引:7,自引:0,他引:7
We have analysed 998 Arabidopsis intron sequences in the EMBL database. All Arabidopsis introns to adhere to the :GU...AG: rule with the exception of 1% of introns with :GC at their 5 ends. Virtually all of the introns contained a putative branchpoint sequence (YUNAN) 18 to 60 nt upstream of the 3 splice site. Although a polypyrimidine tract was much less apparent than in vertebrate introns, the most common nucleotide in the region upstream of the 3 splice site was uridine. Consensus sequences for 5 and 3 splice sites and branchpoint sequences for Arabidopsis introns are presented. 相似文献
120.
A new major histocompatibility complex class I b gene expressed in the mouse blastocyst and placenta
Susan L. Sipes Maxine V. Medaglia Deborah L. Stabley Craig S. DeBruyn Mark S. Alden Vicki Catenacci C. P. Landel 《Immunogenetics》1996,45(2):108-120
Because of the role major histocompatibility complex (MHC) class I b molecules may play during mouse embryonic development,
we thought it would be interesting to search for additional MHC class I b molecules that might be expressed in preimplantation
embryos, and in particular in the trophoblastic lineage. We therefore screened a mouse preimplantation blastocyst cDNA library
for MHC class I sequences. This search led to the identification and characterization of a new MHC class I b gene, blastocyst MHC. Sequences identical to the exons and 3′ untranslated region of this gene have been found in many laboratory mouse strains,
as well as in the related mouse species Mus spreciligus. The presence of this gene in mouse strains of different MHC class I haplotypes argues that blastocyst MHC is a unique, newly-described gene rather than a new allele of a previously described mouse MHC class I gene. Blastocyst MHC has the structure of an MHC class I b gene, with the six exons characteristic of T-region genes. It is linked to H2-D. The amino acid sequence encoded by this gene maintains all the features of a functional antigen-presentation domain. The
blastocyst MHC gene, like the human class I b gene HLA-G, is expressed at the blastocyst stage and in the placenta, and may be the mouse analog for HLA-G.
Received: 31 May 1996 / Revised: 19 August 1996 相似文献