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

IS112 is a transposable element identified in Streptomyces albus G by its frequent mutagenic insertion into the genes for the SalI restriction-modification system. IS112 is present in several copies in the genome of S. albus G. Homologous sequences were detected in other Streptomyces strains. Sequence analysis revealed that IS112 has a length of 883 bp with a GC content of 67.4%. The copy that was isolated contained imperfect inverted repeats (16/20 match) at its ends and was flanked by a 2 bp duplication at the target site, which was located within the gene (salIR) for the SalI endonuclease. A long open reading frame (ORF) encoding a putative polypeptide of 256-253 amino acids spans almost the entire sequence. Significant homology was detected between this polypeptide and that corresponding to ORFB of IS493, an insertion sequence recently isolated from Streptomyces lividans 66.
Mol Gen Genet 1991 Jan
PMID:Isolation and genetic structure of IS112, an insertion sequence responsible for the inactivation of the SalI restriction-modification system of Streptomyces albus G. 184 88

Glucocorticoid-induced lymphocyte cell death is a programmed process which is thought to involve the calcium-dependent degradation of DNA into multiples of 180 basepairs, characteristic of internucleosomal degradation. We have used the glucocorticoid-sensitive mouse lymphoma cell line S49.1 [wild-type (wt)] and the glucocorticoid-resistant cell line S49.22r (nt-) to evaluate the role of both glucocorticoid receptors and calcium in the regulation of internucleosomal DNA degradation and expression of calcium-dependent deoxyribonuclease activity. DNA was isolated from untreated (control) and dexamethasone (dex)-treated viable cells and analyzed for internucleosomal DNA degradation by agarose gel electrophoresis, followed by ethidium bromide staining. Glucocorticoid treatment resulted in substantial internucleosomal DNA degradation in wt cells, but not in nt- cells. This effect was inhibited by coincubation of cells with dex and the glucocorticoid receptor antagonist RU486. In contrast to the glucocorticoid response, administration of either of two calcium ionophores, ionomycin or A23187, produced internucleosomal degradation of DNA in both wt and nt- cells, although the latter were less sensitive to ionophore treatment. Interestingly, A23187 treatment also resulted in a loss of cell viability in HeLa S3 cells, a cell line that does not exhibit glucocorticoid-induced apoptosis. No internucleosomal DNA degradation was detected in HeLa S3 cells killed by A23187. To determine whether similar nucleases are associated with this internucleosomal DNA degradation resulting from both glucocorticoid and calcium ionophore treatment, 0.3 M NaCl nuclear protein extracts were prepared from control and treated cells and analyzed for protein composition or nuclease activity. To assay for nuclease activity, nuclear extracts were electrophoresed in sodium dodecyl sulfate-polyacrylamide gels impregnated with [32P]DNA. Nuclease activity was detected by removal of sodium dodecyl sulfate from the gel, activation with calcium, and subsequent visualization of the loss of [32P]DNA by autoradiography. Dex treatment of wt cells resulted in the appearance of several proteins within the mol wt range of 12-18 kDa, only one of which (16-18 kDa) exhibited calcium-dependent nuclease activity. The appearance of these proteins in nuclear extracts was inhibited by coincubation of glucocorticoid-treated cells with RU 486. Glucocorticoid treatment did not result in the appearance of nuclease activity in nuclear extracts from nt- cells. Interestingly, A23187 or ionomycin treatment resulted in an increase in activity of the 16- to 18-kDa nuclease in both wt and nt- cells. These findings indicate that both glucocorticoid receptors and calcium may share common features in the regulation of apoptosis in lymphoid cells.
Mol Endocrinol 1991 Aug
PMID:Similar actions of glucocorticoids and calcium on the regulation of apoptosis in S49 cells. 194 10

The NgoPII restriction endonuclease, which recognizes the sequence 5'-GG decreases CC-3', differs from its isoschizomer HaeIII in being sensitive to methylation at the external cytosine residue. The entire nucleotide sequence of a cloned 3.3 kb segment of Neisseria gonorrhoeae strain P9 chromosomal DNA which harbours the NgoPII restriction-modification system has been determined. This data, coupled with sub-cloning experiments, indicates that the restriction endonuclease (R.NgoII) and modification (M.NgoII) genes are transcribed from separate promoters but are arranged in tandem, with the R.NgoPII gene being located on the 5' side of the M.NgoPII gene. Unlike all previously reported restriction systems the 3' end of the endonuclease open reading frame overlaps the 5' end of the methylase open reading frame by 8 codons. This overlap may have implications for the regulation of the NgoPII restriction-modification system.
Mol Gen Genet 1989 Apr
PMID:Nucleotide sequence and genetic organization of the NgoPII restriction-modification system of Neisseria gonorrhoeae. 250 49

A transcriptional fusion of the recE gene to a reporter gene has been constructed. Expression of recE was found to be induced upon damage to DNA with either mitomycin C or nalidixic acid. This specific transcriptional induction is blocked by a recE mutation. Mutations affecting the recB, recF and recL gene products markedly reduced induction. However, derepression of recE seems to be independent of the ATP-dependent DNase activity of the exonuclease V enzyme (also called AddAB enzyme).
Mol Microbiol 1989 Sep
PMID:Expression of the recE gene during induction of the SOS response in Bacillus subtilis recombination-deficient strains. 250 72

Human hereditary diseases such as xeroderma pigmentosum, Fanconi's anemia, ataxia telangiectasia, and Bloom's syndrome are characterized by a proneness for developing cancer associated with abnormalities in the processing of DNA damage. The molecular defects responsible for predisposing human tissues to cancer are still not well understood, despite the fact that a considerable amount of work has already been done on this problem. In this paper, we show that in human tumor cell lines, in cells transformed by DNA tumor viruses, and in cells derived from certain cancer-prone disorders, the level of activity of a 42-kDa deoxyribonuclease is many times higher than in diploid untransformed control cells. This suggests that this activity is linked to, or may play a role in, malignant transformation.
Mol Carcinog 1989
PMID:Enhanced deoxyribonuclease activity in human transformed cells and in Bloom's syndrome cells. 280 19

Extracts of Rad+ and radiation-sensitive (rad) mutants of the yeast Saccharomyces cerevisiae were examined for total Mg2+-dependent alkaline deoxyribonuclease activity and the presence of a nuclease that crossreacts immunologically with an antiserum raised against an endo-exonuclease from Neurospora crassa, an enzyme exhibiting both deoxyribo- and ribonuclease activities. No significant differences were observed in total deoxyribonuclease activity between Rad+ and rad mutants. The antibody precipitable activity, however, was found to be 30%-40% of the total alkaline deoxyribonuclease activity in logarithmically growing Rad+ cells. Extracts of stationary phase cells were lacking in antibody precipitable activity. Using immunoblot methods, a 72 kDa crossreacting protein was identified from logarithmically growing cells that was absent from stationary phase cells. In all radiation-sensitive mutants examined, except rad52, at least 20% of total activity was precipitable. Extracts from logarithmically growing rad52 mutants, including a rad52::LEU2 insertion mutant, exhibited less than 10% of the Rad+ precipitable activity; however, some crossreacting material was detected. Although, the level of endo-exonuclease activity is influenced by the RAD52 gene, it is not the product of this gene. The total deoxyribonuclease and the antibody precipitable endo-exonuclease activities were also followed during meiosis. Unlike the Rad+ strain which had previously been shown to have increased levels of total and immunoprecipitable endo-exonuclease as cells underwent meiosis, the rad52 mutant exhibited no increases in either category of nuclease activity. Given the importance of the RAD52 gene in repair, recombination and mutagenesis, the endo-exonuclease may be a significant component of these processes.
Mol Gen Genet 1988 Jan
PMID:An endo-exonuclease activity of yeast that requires a functional RAD52 gene. 283 Apr 67

Replacement of the amino-terminal 40-amino-acid region of the 588-amino-acid precursor of the membrane-bound penicillin-binding protein 3 (PBP3) by the decapeptide MKGKEFQAWI was carried out by altering the amino-coding end of the ftsI gene. Insertion of the modified gene into a runaway-replication plasmid under the control of a fused lpp promoter and lac promoter/operator, resulted in the overexpression by Escherichia coli of the modified PBP3 (designated PBP3**) in the cytoplasm. About 80% of the accumulated PBP3** underwent sequestration in the form of insoluble protein granules that were isolated by cell breakage or cell lysis. After selective removal of contaminants by an EDTA-lysozyme/DNase (deoxyribonuclease)/Nonidet extraction, treatment of the granules with guanidinium chloride followed by dialysis against buffer containing 0.5 M NaCl yielded a refolded, water-soluble PBP3**, which, upon chromatography on Superose 12, exhibited the expected 60,000 molecular mass. The refolded PBP3** bound benzylpenicillin in a 1 to 1 molar ratio, was highly sensitive to aztreonam and showed the same degree of thermostability, in terms of penicillin-binding capacity, as the parent, membrane-bound PBP3, suggesting that protein refolding occurred with formation of the correct intramolecular interactions. Two to three mg of refolded PBP3** can be obtained from 1 litre of culture of the overproducing strain.
Mol Microbiol 1988 Jul
PMID:Overexpression, solubilization and refolding of a genetically engineered derivative of the penicillin-binding protein 3 of Escherichia coli K12. 305 Mar 60

Strain 1485IN and its derivatives were found to have a large inversion extending to about 35% of the chromosome. Because of this, the question arose as to whether 1485IN had arisen from an Escherichia coli strain other than K12. However, 1485IN had a flagellar antigen and a restriction-modification system indistinguishable from those of W3110, a major line of K12, and had retained an amber suppressor and lambda sensitivity that are characteristics of W1485 from which this strain seems to have arisen. Strain 1485IN had acquired proline auxotrophy, but showed the same growth rate as W1485 in nutrient broth at 37 degrees C. Interrupted matings with Hfr strains of 1485IN revealed a gene arrangement of nalA-gal-trp-his-lac-proA-thrleu-ilv, in which gal, trp, and his were on the inverted segment. The termini of the inversion were inferred to be situated between tsx (9.5 min) and purE (12 min) and between his (44 min) and cdd (46.5 min).
Mol Gen Genet 1986 Nov
PMID:A naturally occurring large chromosomal inversion in Escherichia coli K12. 354 22

The genes for restriction-modification system EcoRII have been cloned from plasmid N3 DNA using RSF2124 as a vector plasmid. The hybrid plasmids designated pFK321 and pFK322 contained a 5.8 megadaltons EcoRI--fragment derived from N3 DNA including the genes for restriction-modification system EcoRII and a gene for resistance to sulfanilamide.
Mol Gen Genet 1980
PMID:Molecular cloning of EcoRII endonuclease and methylase genes. 624 37

Further research on bacteriophage T7 DNA penetration mechanism into E. coli cells during the infection was carried out. The DNA-RNA-hybridization on nitrocellulose filters revealed that in the presence of chloramphenicol the T7 DNA penetration from the virion into a host cell was coupled with its transcription by the bacterial RNA polymerase. The data obtained indicate that in the absence of antibiotics the penetration of a part of T7 genome which correspondes to class II and III genes is coupled with its transcription by a phage-specific RNA polymerase. Along with this the host restriction-modification system when its activity is not inhibited by the phage-induced proteins will be able to cleave the penetrated T7 DNA just after its transcription was accomplished. Considering these data along with our conception on direct involvement of transcription in T7 DNA penetration process during the infection one can suggest that E. coli RNA polymerase molecules which provide the phage DNA transport, are localized at the inner surface of cytoplasmic membrane.
Mol Biol (Mosk)
PMID:[Coupling of bacteriophage T7 DNA penetration with its transcription, during infection]. 635 19


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