Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The expressed immunoglobulin gamma 2b (IgG2b) heavy-chain gene of 4T001 was cloned into the shuttle vector pSV2-gpt and transfected into myeloma J558L and lymphoma A20.2J. Northern blots indicated that the transfected gamma 2b gene was processed in a manner similar to the endogenous heavy chain in both lymphoma and myeloma cells. To identify sequences important for immunoglobulin mRNA processing, we constructed deletions around the secretion-specific polyadenylation site and introduced the deleted genes into J558L cells. The BAL deletion lacked 670 base pairs of intervening sequence between secreted and membrane regions; the Kpn deletion lacked 830 base pairs in this region. J558L cells transfected with either the entire gamma 2b gene or the delta BAL vector produced predominantly secretion-specific gamma 2b mRNA and protein. J558L cells transfected with the delta Kpn vector produced approximately equimolar amounts of secretion-specific and membrane-specific gamma 2b mRNA. Both 55,000-dalton secreted and 62,000-dalton putative surface IgG2b proteins were detected in the delta Kpn transfectants. We conclude that sequences absent in the Kpn deletion but present in the BAL deletion exert an important role in the production of secretion-specific mRNA. The Kpn deletion removes the normal site of cleavage and poly(A) addition, and it is possible that it is the absence of this site which changes the processing pattern. Alternatively, it is possible that sequences absent in the Kpn deletion but present in the BAL deletion function in regulating the production of predominantly secretion-specific mRNA in myeloma cells. The possible role of a highly conserved sequence found in this region is discussed.
Mol Cell Biol 1986 May
PMID:Sequences near the 3' secretion-specific polyadenylation site influence levels of secretion-specific and membrane-specific IgG2b mRNA in myeloma cells. 287 62

The herpes simplex virus (HSV) type 1 thymidine kinase gene (tk) was resected from its 3' end with BAL 31 exonuclease. Two sets of plasmids were isolated that lacked information distal to the two copies of the hexanucleotide 5'-AATAAA-3' located at the 3' end of the HSV tk gene. The presence of a simian virus 40 origin of DNA replication in each plasmid facilitated analysis of patterns of transcription in transfected Cos-1 monkey cells. Transcription analyses were performed with an S1 nuclease protection assay. Efficient processing and polyadenylation at the normal site still occurred when all sequences more than 44 or 46 base pairs (bp) downstream from the first AATAAA were removed (pTK311R/SV010 and pTK209R/SV010). Removal of an additional 7 bp (pTK312R/SV010) decreased the amount of tk mRNA processed at that normal site, and tk mRNA polyadenylated at a cryptic site within pBR322 sequences began to appear. The normal processing and polyadenylation site was not used at all when an additional 12 bp was removed (pTK314R/SV010); the small amount of tk mRNA produced was processed and polyadenylated at the cryptic pBR322 site. The region of the tk gene critical for efficient processing and polyadenylation of tk mRNA is located 20 to 38 bp downstream from the first AATAAA, distal to the polyadenylation site, and as RNA can form a stem-loop structure containing AAUAAA. Similar G + T-rich elements were located in DNA fragments which substitute efficiently for the HSV tk processing and polyadenylation signal and were not found in AATAAA-containing DNA fragments which substitute inefficiently for the HSV tk signal.
Mol Cell Biol 1985 Aug
PMID:Identification of sequences in the herpes simplex virus thymidine kinase gene required for efficient processing and polyadenylation. 301 51

To initiate a genetic analysis of yeast ribosomal protein gene promoters, we have constructed a gene fusion between the yeast ribosomal protein gene RP39A and the Escherichia coli lacZ gene. This gene fusion contains approximately 1,030 nucleotides of the 5' flanking region and the first 49 1/3 codons of RP39A fused in frame to a large 3' end fragment of lacZ. Whether it is introduced into yeast cells on a moderately high-copy-number plasmid, or integrated into the yeast genome at the RP39A locus, this RP39A-lacZ gene directs the synthesis of a hybrid transcript which encodes beta-galactosidase activity. Deletions in the 5' flanking region of RP39A-lacZ were constructed by linker insertion and BAL 31 mutagenesis. The expression of the mutant genes in yeast cells was assayed by measuring RP39A-lacZ mRNA and beta-galactosidase levels. By these means we have shown that the sequences between nucleotides -256 and -170 upstream of RP39A are essential for expression of this gene. Three sequence motifs, HOMOL1, RPG, and a T-rich region, which were found in that order 5'----3' upstream of most yeast ribosomal protein genes, were present within this interval. We found that substitution of the CYC1-lacZ upstream activation site with the fragment from nucleotides -298 to -172 upstream of RP39A, containing the HOMOL1-RPG-T-rich motif in that 5'----3' orientation, fully restored expression of the CYC1-lacZ gene. The essentially of HOMOL1, the RPG sequence, and the T-rich region for wild-type levels of expression of RP39A, the conserved location and order of these sequence motifs in yeast ribosomal protein genes, and the ability of a DNA fragment carrying these three sequence elements to substitute for the upstream activation site regions of CYC1 indicate that these three oligonucleotides may be essential to the transcription of yeast ribosomal protein genes.
Mol Cell Biol 1986 Feb
PMID:Tripartite upstream promoter element essential for expression of Saccharomyces cerevisiae ribosomal protein genes. 302 62

We analyzed a cloned fragment of the yeast URA3 promoter region that contains a sequence of DNA capable of functioning as a highly efficient transcription terminator. BAL 31 deletions have shown the signal for the transcription termination activity is less than or equal to 110 base pairs and resides between bases 45 and 155 upstream of the URA3 primary ATG codon at base 227. In our in vivo assay system, the DNA fragment is able to terminate transcripts very efficiently in either orientation. The terminated transcripts bind to oligodeoxythymidylate cellulose columns and promote the synthesis of full-length cDNAs, suggesting that the transcripts are polyadenylated. The 110-base-pair region contains no sequence resembling terminator consensus sequences described by Zaret and Sherman (K.S. Zaret and F. Sherman, Cell, 28:563-573, 1982) or Henikoff and Cohen (S. Henikoff and E.H. Cohen, Mol. Cell. Biol., 4:1515-1520, 1984). We discuss the possible physiological relevance of this sequence to bona fide termination of transcription and to URA3 regulation in Saccharomyces cerevisiae.
Mol Cell Biol 1986 Apr
PMID:Transcription terminator-like element within a Saccharomyces cerevisiae promoter region. 302 68

A series of BAL 31 deletions were constructed in the upstream region of the Saccharomyces cerevisiae CYC7 gene to determine sequences required for transcriptional initiation. These deletions identified the TATA box as an alternating A-T sequence at -160 and the initiation sequences as well as the spatial relationship between them. The TATA box was necessary for wild-type levels of expression of the CYC7 gene. Decreasing the distance between the TATA sequence and the initiation site did not alter gene expression, but the site of transcription was shifted 3'-ward. In most cases, transcription initiated at a number of sites, the 5'-most of which was the first suitable site greater than 45 base pairs 3' of the TATA sequence, suggesting a spatial relationship between these sequences. Consensus sequences previously proposed for initiation sites were evaluated with respect to the start sites identified in this study as well as the start sites of other yeast genes.
Mol Cell Biol 1987 Oct
PMID:Sequences required for transcriptional initiation of the Saccharomyces cerevisiae CYC7 genes. 331 87

Alloxan is known to inhibit pancreatic B cell and liver glucokinase and glucose protects the enzyme against inhibition. The dithiol 1,4-dithiothreitol (1,4-DTT) protected against and reversed the inhibition of glucokinase by alloxan. An investigation into the structure-activity relationship using a variety of different dithiols demonstrated that the ability of the dithiols to protect against and to reverse the inhibition of glucokinase by alloxan was dependent on the spacing between the SH (thiol) groups of the various dithiols. Only 1,3-dimercaptopropane, 1,4-dimercaptobutane, 1,4-dithioerythritol, and 1,4-DTT, with intermediate spacing between the SH groups, reversed the inhibition of glucokinase induced by alloxan. Dithiols with two vicinal SH groups such as 1,2-dimercaptoethane and 2,3-dimercaptopropanol (BAL) were ineffective in the same way as dithiols with more widely spaced SH groups such as 1,5-dimercaptopentane and 1,6-dimercaptohexane. Except for 1,6-dimercaptohexane, all dithiols also protected glucokinase against the inhibition of alloxan. The monothiol cysteine, but not glutathione, a tripeptide monothiol, also protected glucokinase against alloxan inhibition but both were unable to reverse the inhibition. Like alloxan, other dithiol reagents such as ninhydrin, N-ethylmaleimide, and maleimide inhibited glucokinase. Glucose and 1,4-DTT protected glucokinase against this inhibition. 1,4-DTT partially reversed this inhibition. It is concluded, therefore, that the mechanism of inhibition of glucokinase by alloxan is a reaction of alloxan with two adjacent SH groups in the depth of the sugar-binding site of the glucokinase, with formation of a disulfide bond and concomitant inactivation of the enzyme. Because glucokinase can couple changes in the blood glucose concentration to changes in the glycolytic flux rate and corresponding changes in the rate of insulin secretion, it may function as a glucose signal recognition enzyme in the pancreatic B cell. This mechanism of interaction of alloxan with glucokinase may thereby provide an explanation for the ability of alloxan to inhibit glucose-induced insulin secretion.
Mol Pharmacol 1988 Sep
PMID:Inhibition of glucokinase by alloxan through interaction with SH groups in the sugar-binding site of the enzyme. 341 26

DNA sequence analysis of wild-type and mutant ADH2 loci suggested that two unusual features 5' of the promoter, a 22-base-pair perfect dyad sequence and a (dA)20 tract, were important for regulation of this gene (D. W. Russell, M. Smith, D. Cox, V. M. Williamson, and E. T. Young, Nature [London] 304:652-654, 1983). Oligonucleotide-directed mutagenesis was used to construct ADH2 genes lacking the 22-base-pair dyad or the (dA)20 tract (V.-L. Chan and M. Smith, Nucleic Acids Res. 12:2407-2419, 1984). These mutant genes and other ADH2 deletions constructed by BAL 31 endonuclease digestion were studied after replacing the wild-type chromosomal locus with the altered alleles by the technique of gene transplacement (T. L. Orr-Weaver, J. W. Szostak, and R. S. Rothstein, Proc. Natl. Acad. Sci. USA 78:6354-6358, 1981), using canavanine resistance as the selectable marker. Deletions lacking the dyad failed to derepress normally and did not respond to mutations at the ADR1 locus, which encodes a protein necessary to activate ADH2. Deletions of the (dA)20 tract did not have a detectable phenotype. A small deletion located just 3' to the (dA)20 tract (between positions -164 and -146) had a low amount of ADR1-dependent transcription during repressed growth conditions, indicating that the regulatory protein encoded by ADR1 is present in a potentially active form during repression and that alterations of a DNA sequence in the promoter region can unmask its latent activity.
Mol Cell Biol 1986 Jun
PMID:ADR1-mediated regulation of ADH2 requires an inverted repeat sequence. 353 11

In order to characterize the tandem rrnB promoters transcribing one of the ribosomal RNA operons in E. coli we subcloned the basic promoter unit. This 185 bp fragment extends from -64 to +121 counted from the transcription start site of upstream promoter P1. The start site of downstream promoter P2 is also included in the promoter cartridge. S1 mapping experiments show that both promoters on this fragment are active in vivo. BAL-31 deletion mutations generated at the start site for promoter P2 were also tested by S1 mapping. Transcription from P2 remained active in all cases with the exception of one construction which lacks the -10 region. This demonstrates that the sequences downstream from the -10 region of P2 are not essential for basic promoter function.
Mol Gen Genet 1985
PMID:In vivo transcription from deletion mutations introduced near Escherichia coli ribosomal RNA promoter P2. 388 50

We have previously identified an 11-base DNA sequence, 5'-G-G-T-A-C-C-T-A-A-C-C-3' (simian virus 40 [SV40] map position 294 to 304), which is important in the control of SV40 late RNA expression in vitro and in vivo (Brady et al., Cell 31:625-633, 1982). We report here the identification of another domain of the SV40 late promoter. A series of mutants with deletions extending from SV40 map position 0 to 300 was prepared by nuclease BAL 31 treatment. The cloned templates were then analyzed for efficiency and accuracy of late SV40 RNA expression in the Manley in vitro transcription system. Our studies showed that, in addition to the promoter domain near map position 300, there are essential DNA sequences between nucleotide positions 74 and 95 that are required for efficient expression of late SV40 RNA. Included in this SV40 DNA sequence were two of the six GGGCGG SV40 repeat sequences and an 11-nucleotide segment which showed strong homology with the upstream sequences required for the efficient in vitro and in vivo expression of the histone H2A gene. This upstream promoter sequence supported transcription with the same efficiency even when it was moved 72 nucleotides closer to the major late cap site. In vitro promoter competition analysis demonstrated that the upstream promoter sequence, independent of the 294 to 304 promoter element, is capable of binding polymerase-transcription factors required for SV40 late gene transcription. Finally, we show that DNA sequences which control the specificity of RNA initiation at nucleotide 325 lie downstream of map position 294.
Mol Cell Biol 1984 Jan
PMID:Simian virus 40 major late promoter: an upstream DNA sequence required for efficient in vitro transcription. 632 50

cis-Diamminedichloroplatinum(II) was found to bind to covalently closed circular supercoiled, covalently closed circular nonsupercoiled, and single-strand broken relaxed PM2 DNA and induce different types of DNA conformational changes. Using Kleinschmidt's technique, it was found that binding of cis-diamminedichloroplatinum(II) decreased the DNA length to 75% of the original single-strand broken relaxed DNA without inducing superhelical conformational changes. cis-Diamminedichloroplatinum(II) also shortened the length of covalently closed circular nonsupercoiled DNA before a supercoiled conformation was generated. Single strand-specific nucleases were used to detect drug-induced DNA structural alterations. Local single-strand regions or regions of denaturation were detected by S1 nuclease from Aspergillus oryzae and by BAL-31 nuclease from Alteromonas espejiana BAL-31. The single-strand regions or local denaturation regions do not seem to be related to or caused by DNA superhelical conformational changes since they were detected at drug concentrations at which no significant DNA superhelical turns were found. DNA shortening, superhelical conformational changes, and local denaturation regions can be explained by the previously proposed "DNA intrastrand cross-linking" model (Stone et al., J. Mol. Biol., 104: 793-801, 1976).
 ...
PMID:DNA supercoiling, shortening, and induction of single-strand regions by cis-diamminedichloroplatinum(II). 719 92


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>