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)

Plasmid pC194-1, a mutant of pC194, and chimeric derivatives of pC194-1 are segregationally unstable in B. subtilis. Such instability could be enhanced by exposure of pC194-1-carrying cells to methyl methanesulfonate. pC194-1 is distinct from pC194 in the addition of two A:T base pairs within the previously defined D region of pC194. Complementation experiments between pC194-1 and other plasmids suggest that the mutation of pC194-1 interferes with the production of a diffusible gene product required for plasmid maintenance.
Mol Gen Genet 1985
PMID:A gene controlling segregation of the Bacillus subtilis plasmid pC194. 392 93

The RAD52 gene of Saccharomyces cerevisiae, which is involved in genetic recombination and DNA repair, was cloned by transformation of rad52-1 mutant cells to methyl methanesulfonate resistance with BamHI fragments of Rad+ genomic DNA inserted into the Escherichia coli-S. cerevisiae shuttle vector YRp7. A plasmid carrying a 2.0-kilobase BamHI fragment was found to partially complement methyl methanesulfonate sensitivity of the rad52-1 mutant. By using this fragment as a hybridization probe, a plasmid that fully complemented the methyl methanesulfonate sensitivity of the mutant was isolated, which carries a 3.3-kilobase SalI fragment containing most of the 2.0-kilobase BamHI fragment. Analysis of the nucleotide sequence of the SalI fragment revealed the presence of a large open reading frame of 1,512 nucleotides. The rad52-1 mutant DNA has a single-base change in this reading frame, which leads to an amino acid substitution. Analysis of mRNA synthesized in yeast by the S1 mapping technique disclosed possible transcription initiation and termination points of the RAD52 gene and suggested formation of the gene product without splicing of the transcript.
Mol Cell Biol 1984 Dec
PMID:Primary structure of the RAD52 gene in Saccharomyces cerevisiae. 609 21

Epithelial keratinization in fragments of fetal rat forestomach in organ culture was significantly accelerated by treatment with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) for 1 h (Fukamachi and Takayama 1979). In this paper, we examined whether acceleration of epithelial keratinization may be characteristic for some carcinogens, and also the mechanism of acceleration of epithelial keratinization by treatment with MNNG. Forestomach epithelial keratinization was accelerated by treatments with 4-nitroquinoline-1-oxide, N-acetoxy-2-acetylaminofluorene, 1-methyl-1-nitrosourea, 7,12-dimethylbenzanthracene, methyl methanesulfonate, and MNNG, but not with 2-acetylaminofluorene, pyrene, or dimethylsulfoxide, indicating that carcinogens may specifically accelerate epithelial keratinization. Chemicals that accelerated epithelial keratinization inhibited epithelial mitotic activity on day 1 in culture, but the mitotic rate was restored to the control level from day 2 onwards. The epithelial keratinization was completely inhibited by adding 5 micrograms/ml of retinoic acid (RA) to the culture medium, irrespective of treatment with MNNG. Addition of 1 microgram/ml of RA suppressed epithelial keratinization in control explants more than in MNNG-treated explants. One possible explanation is that the epithelial cells become less sensitive to RA after MNNG-treatment. A mechanism is proposed assuming that carcinogens induce some qualitative changes in epithelial cells by inhibiting cell proliferation on day 1 in culture, and consequently the epithelial keratinization is accelerated.
Virchows Arch B Cell Pathol Incl Mol Pathol 1984
PMID:Acceleration of epithelial keratinization by carcinogens in fetal rat forestomach in organ culture. 620 61

Survival of HA1 or MMS-treated T4 and lambda phages was estimated in bacterial cells differing in their ability to repair DNA. It has been found that the mismatch repair system of the bacterial host, which involves mutS mutR MutL uvrE and dam loci, does not excise, or does so to only a limited extent, the nonpaired bases from DNA of HA or MMS-treated phages. Mutation in polA, both in the polymerase as well as in the 5' leads to 3' exonuclease activity, have a small effect on survival of HA-treated phages, whereas mutation in the polymerase activity has a pronounced effect on survival of MMS-treated phages. There was a difference in the effect of polA mutations on survival of MMS-treated T4 and lambda phages; the survival of the former was less affected than the latter. Induction of SOS response has no effect on repair of HA and MMS-treated phages. Pretreatment of bacterial host (including the ada- mutant) with low doses of alkylating agents increases the survival of MMS (but not HA)-treated phages; pretreatment of bacteria with HA has no effect on survival of HA-treated phages. Three lines of evidence: the different inactivation rates of MMS-treated T4 and lambda phages, variation in the effect of polA mutations on survival of T4 and lambda phages, and a different level of adaptive response in ada- cells towards of MMS-treated T4 and lambda phages, suggest that the patterns of DNA methylation in T4 and lambda phages are different.
Mol Gen Genet 1982
PMID:Effect of bacterial host repair systems on the viability of hydroxylamine and methyl methanesulfonate treated T4 and lambda bacteriophages. 621 98

Twenty Tn5 insertion mutants of the drug resistance plasmid pKM101 have been isolated that are unable to enhance mutagenesis with ultraviolet (UV) irradiation or methyl methanesulfonate. By restriction mapping, the Tn5 insertion in each of these pKM101 mutants was shown to be within a 1.9 kb region of the plasmid genome. We have termed this segment of the pKM101 map the muc (mutagenesis: UV and chemical) gene(s). Characterization of these mutants indicated that any Tn5 insertion within the muc gene(s) abolished the ability of pKM101 to: (a) enhance spontaneous, UV and chemical mutagenesis, (b) increase host survival following UV-irradiation, (c) increase the survival of UV-irradiated phage plated on irradiated or unirradiated cells, and (d) suppress the repair and mutagenesis deficiencies of a umuC- mutant. Possible models to explain the role of the pKM101 muc gene(s) in mutagenesis and repair are discussed.
Mol Gen Genet 1980
PMID:Localization of the plasmid (pKM101) gene(s) involved in recA+lexA+-dependent mutagenesis. 625 13

Three-dimensional models of the picrotoxinin and alkyl-substituted gamma-butyrolactone (GBL) receptor sites were constructed with the aid of a molecular graphics computer system (MMS-X). These two independently derived models proved to be very compatible, which suggested that both types of compounds share a common site of action. Since picrotoxinin is known to act at gamma-aminobutyric acid-regulated chloride channels, a hypothesis was made and tested that the convulsant GBL and picrotoxinin analogues physically impede the passage of chloride ions through the channel. It was also shown that it was theoretically possible for the anticonvulsant GBLs to act at this same site without blocking chloride flux. Finally, the model was applied to several convulsant and anticonvulsant compounds of different chemical classes and was found to be of somewhat general applicability.
Mol Pharmacol 1983 Mar
PMID:Computer-assisted modeling of the picrotoxinin and gamma-butyrolactone receptor site. 630 Jun 53

The RAD50 gene was cloned as a 4.8 kb fragment in the 2 mu derived plasmid pFL1. The gene resides in a 3.9 kb segment that was subcloned into the plasmid YRp7. The cloned gene complements the deficiency caused by the rad50-1 mutation with respect to gamma-rays, MMS resistance and UV-induced mitotic recombination. Restoration of the Rad+ phenotype occurs when the cloned gene is on a freely replicating multiple-copy plasmid or in the integrated form. Mapping of the cloned gene following integration of the 2 mu plasmid, and of the subclone in plasmid YRp7, showed it to be located on the left arm of chromosome XIV. Tetrad analysis of various crosses involving two different strains carrying rad50-1 showed the mutation to map next to pet2 on chromosome XIV, and not on the right arm of chromosome IV, as previously published.
Mol Gen Genet 1984
PMID:Cloning and mapping of the RAD50 gene of Saccharomyces cerevisiae. 632 24

The product of the uvrD gene of Escherichia coli is involved in the repair of DNA damage, mismatch repair, and recombination. Phage Mud(Amp, Lac) was used to form a uvrD-lacZ fusion allowing uvrD expression to be followed by measuring the activity of beta-galactosidase, the product of the lacZ gene. uvrD expression was inducible by DNA damage and was under the control of lexA-recA regulatory system. Mutations in the uvrD gene that result in different phenotypes in respect to DNA repair and spontaneous mutation have been previously found. The phenotype of the uvrD::Mud(Amp, Lac) mutant was mutator and UV-sensitive but not as deficient in host cell reactivation or repair of methyl methanesulfonate damage as the previously described uvrD3 mutant.
Mol Gen Genet 1983
PMID:The Escherichia coli uvrD gene is inducible by DNA damage. 635 63

Six recessive second chromosomal mutants of Drosophila melanogaster exhibiting larval hypersensitivity to methyl methanesulfonate have been identified and assigned to six complementation groups. The strains have been analyzed for their sensitivities to UV, X-ray, nitrogen mustard and formaldehyde. Two classes of mutants not previously observed in Drosophila have been identified. The mus 204A1 and mus 205A1 mutants exhibit sensitivity to MMS and UV but not X-ray or nitrogen mustard, while the mus 206A1 and mus 207A1 mutants display sensitivity to MMS, UV, and nitrogen mustard. Four of the seven strains exhibit poor female fertility and two of these are shown to have a weak meiotic disjunctional defect. Biochemical studies of the mus 205A1 mutant suggest a defect in DNA synthetic ability associated with excision and postreplication repair performed on UV and alkylation-damaged templates (Boyd and Harris 1981; Brown and Boyd 1981 b; R.L. Dusenbery, manuscript in preparation).
Mol Gen Genet 1982
PMID:Mutagen sensitivity of Drosophila melanogaster. V. Identification of second chromosomal mutagen sensitive strains. 681 27

This paper describes studies to determine the role of the umuC gene product in the process of alkylation induced mutagenesis. An active umuC gene is necessary for most MMS induced mutagenesis but it is not essential for EMS nor for MNNG induced mutagenesis in either normal or adapted cultures. In this respect the umuC mutation differs from lexA mutations which have a striking effect on MNNG induced mutagenesis (Schendel, et al., 1978). These findings have prompted a re-evaluation of these previously published data and the advancement of an hypothesis which explains the lexA effect without evoking a role for error-prone repair in the process of alkylation induced mutagenesis. It was also observed that exposure to MNNG is capable of generating a small amount of W-reactivation and W-mutagenesis capacity in a umuC strain which is totally blocked for UV induced reactivation. In light of this result a possible function for the umuC gene product is discussed.
Mol Gen Genet 1980
PMID:The role of umuC gene product in mutagenesis by simple alkylating agents. 699 71


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