A temperature-sensitive mre11-1 mutation of Saccharomyces cerevisiae causes defects in meiotic recombination and DNA repair during vegetative growth at a restrictive temperature. We cloned the MRE11 gene found that it encodes 643-amino acid protein with highly acidic region containing heptad repeat Asp its C-terminus is located downstream YMR44 near RNA1 locus on right arm chromosome XIII. Transcripts increased transiently showed same kinetics as RAD50 meiosis. In mre11 disruption mutant...

The restriction map of a BamHI DNA fragment that contains the recA gene Escherichia coli has been established and large portion fragment's nucleotide sequence determined. coding region 1059 residues encodes single protein 353 amino acid residues. first five NH2 terminus agrees with predicted from except for absence formylmethionine in purified protein. Immediately after sequence, there is G+C-rich dyad symmetry followed by an A+T-rich sequence. These could signal termination transcription....

The human RAD51 protein is a homologue of the bacteria RecA and yeast proteins that are involved in homologous recombination DNA repair. interacts with also tumor suppressor p53 breast cancer susceptibility gene 1 (BRCA1). We have used two-hybrid system to clone murine cDNA sequences encode two RAD51-associated molecules, RAB22 RAB163. RAB163 encodes C-terminal portion mouse BRCA2, second humans, demonstrating an vitro association between BRCA2. novel product vitro. To detect interactions...

Using complementation tests and nucleotide sequencing, we showed that the rad58-4 mutation was an allele of MRE11 gene have renamed mutationmre11-58. Two amino acid changes from wild-type sequence were identified; one is located at a conserved site phosphodiesterase motif, other homologous change nonconserved site. Unlike mre11 null mutations, mre11-58 allowed meiosis-specific double-strand DNA breaks (DSBs) to form recombination hot spots but failed process those breaks. DSB ends this...

Abstract Mutants defective in meiotic recombination were isolated from a disomic haploid strain of Saccharomyces cerevisiae by examining within the leu2 and his4 heteroalleles located on chromosome III. The mutants classified into two new complementation groups (MRE2 MRE11) eight previously identified groups, which include SPO11, HOP1, REC114, MRE4/MEK1 genes RAD52 epistasis group. All mutants, mutations are homozygous diploid, can undergo premeiotic DNA synthesis produce spores. spores are,...

A new mutant, which was sensitive to both methyl-methanesulfonate (MMS) and ultra-violet light (UV) defective in meiotic recombination, isolated from Saccharomyces cerevisiae. The gene, ESR1, cloned by complementation of the MMS sensitivity mutant found be essential for cell growth, as deleted haploid strain lethal. ESR1 gene adjacent CKS1 on chromosome II encoded a putative 2368-amino acid protein with molecular weight 273 k. transcript 8.0 kb long induced during meiosis. predicted Esr1 had...

The MRE11, RAD50, andXRS2 genes of Saccharomyces cerevisiaeare involved in the repair DNA double-strand breaks (DSBs) produced by ionizing radiation and radiomimetic chemicals such as methyl methanesulfonate (MMS). In these mutants, single-strand degradation a 5′ to 3′ direction from DSB ends is reduced. Multiple copies EXO1 gene, encoding exonuclease, were found suppress high MMS sensitivity mutants. exo1 single mutant shows weak sensitivity. When an mutation combined with anmre11 mutation,...

Abstract The RAD54 gene, which encodes a protein in the SW12/SNF2 family, plays an important role recombination and DNA repair Saccharomyces cerevisiae. yeast genome project revealed homologue of RAD54, RDH54/TID1. Properties rdh54/tid1 mutant rad54 double are shown for mitosis meiosis. is sensitive to alkylating agent, methyl methanesulfonate (MMS), defective interchromosomal intrachromosomal gene conversion. single mutant, on other hand, does not show any significant deficiency mitosis....

The Rad51 and Lim15 proteins of lily, which are homologs the bacterial RecA protein, were found on chromosomes in various stages meiotic prophase 1. presence both as discrete foci leptotene zygotene their colocalization suggest that recombination begins at stage with cooperation these continues zygotene. Localization or adjacent to suggests bind chromatin loops extend from axial cores. may participate searching pairing homologous DNA sequences, protein does. different pattern localization...

The nucleotide sequence of a 2.8-kilobase fragment the Escherichia coli chromosome containing umuDC genes has been determined. DNA specifies two open reading frames 417 and 1266 nucleotides encoding proteins with calculated molecular weights 15,063 47,677, respectively. From these previous results genetic biochemical studies on cloned genes, we conclude that former is umuD latter umuC gene. In vitro transcription regulatory region umu operon revealed (i) upstream coding there...

The RAD52 gene of Saccharomyces cerevisiae, which is involved in genetic recombination and DNA repair, was cloned by transformation rad52-1 mutant cells to methyl methanesulfonate resistance with BamHI fragments Rad+ genomic inserted into the Escherichia coli-S. cerevisiae shuttle vector YRp7. A plasmid carrying a 2.0-kilobase fragment found partially complement sensitivity mutant. By using this as hybridization probe, that fully complemented isolated, carries 3.3-kilobase SalI containing...

The eutectic effect of a Li-salt and an amide is caused by the interaction between Li⁺ CO amide. reduction resistance improved substituting N–H with N–CH₃.

All living things are diversified by the genetic recombination and segregation of chromosomes, as well mutations. Genetic is also involved in repair DNA damage, a process that important for normal functioning genes cells. For understanding molecular mechanisms recombination, identification characterization various processes essential.

Comparisons of the amino acid sequences three yeast RecA-like proteins, Rad51 and DMC1 from S.cereviseae S.pombe , revealed several highly conserved regions. Degenerated oligonucleotides encoding two these regions were used for polymerase chain reaction to clone a chicken gene. The encoded protein shares 68% 49% identical acids with proteins. strong sequence conservation between genes indicates that RecA homologues are throughout evolution prokaryots higher eukaryotes. High expression gene...

In the yeast Saccharomyces cerevisiae , meiotic recombination is initiated by DNA double-stranded breaks (DSBs) occurring in micrococcal nuclease (MNase)-hypersensitive regions of chromatin. MNase-sensitive sites also undergo meiosis-specific alterations chromatin structure prior to appearance DSBs. DSB formation requires products numerous genes. Herein we have examined effects mutations four such genes, MRE11 RAD50 XRS2 and MRE2 on MNase sensitivity at premeiotic cells. Disruption each...

Pure recA protein was easily obtained from Escherichia coli harboring plasmid pTM-2 which carried the gene by two chromatographic steps on phosphocellulose and DEAE-cellulose. RecA stable in pH range of 6 to 9 at 25 degrees C. found aggregate highly under these conditions. Lowering concentration, presence glycerol, lowering stability region diminished extent aggregation. The spectroscopic properties were measured 10% (v/v) glycerol. had an absorption maximum 278 nm. value a1% 1cm nm...