Showing papers by "Thomas D. Petes published in 1986"
TL;DR: A genetic analysis of mutant yeast strains that have telomeric tracts that are shorter than normal indicates that these short telomeres are the result of single nuclear recessive mutations and that these mutations can be classified into two different complementation groups.
Abstract: The chromosomes of the yeast Saccharomyces cerevisiae terminate in a tract of simple-sequence DNA [poly(C1-3A)] that is several hundred base pairs long. We describe the identification of mutant yeast strains that have telomeric tracts that are shorter than normal. A genetic analysis of these strains indicates that these short telomeres are the result of single nuclear recessive mutations and that these mutations can be classified into two different complementation groups. The full expression of the mutant phenotype shows a very long lag (approximately equal to 150 cell divisions). From our analysis of these mutants as well as other data, we suggest that the duplication of the telomeric poly(C1-3A) tract involves two processes, semiconservative replication and untemplated terminal addition of nucleotides.
266 citations
TL;DR: To determine the fraction of the yeast Saccharomyces cerevisiae genome that is required for normal cell growth and division, diploid strains that were heterozygous for random single disruptions were constructed and the phenotype of the resulting haploid strains was examined.
150 citations
TL;DR: Recombination between repeated genes on nonhomologous chromosomes occurs much more frequently in meiosis than in mitosis, and reciprocal exchanges between the repeated genes result in chromosomal translocations.
Abstract: We have examined meiotic and mitotic recombination between repeated genes on nonhomologous chromosomes in the yeast Saccharomyces cerevisiae . The results of these experiments can be summarized in three statements. First, gene conversion events between repeats on nonhomologous chromosomes occur frequently in meiosis. The frequency of such conversion events is only 17-fold less than the analogous frequency of conversion between genes at allelic positions on homologous chromosomes. Second, meiotic and mitotic conversion events between repeated genes on nonhomologous chromosomes are associated with reciprocal recombination to the same extent as conversion between allelic sequences. The reciprocal exchanges between the repeated genes result in chromosomal translocations. Finally, recombination between repeated genes on nonhomologous chromosomes occurs much more frequently in meiosis than in mitosis.
134 citations
TL;DR: An insertion of a Ty element into one of the repeated ribosomal RNA genes of yeast is reported and it is found that this insertion, unlike most Ty insertions, is mitotically unstable.
Abstract: The yeast Saccharomyces cerevisiae has about 30 to 50 copies of a transposable element Ty. Most of these elements are located at the 5' ends of protein coding sequences and are flanked by a 5 bp duplication. We report below an insertion of a Ty element into one of the repeated ribosomal RNA (rRNA) genes of yeast. The element is located between the 3' ends of the divergentally transcribed 37S and 5S rRNA's and is not flanked by a 5 bp duplication. In addition, one end of the Ty insertion is contiguous with a 306 bp deletion of the sequences of the rRNA gene. We find that this insertion, unlike most Ty insertions, is mitotically unstable.
11 citations
01 Jan 1986
TL;DR: Examination of meiotic and mitotic recombination between repeated genes on nonhomologous chromosomes in the yeast Saccharomyces cerevisiae found that reciprocal exchanges between the repeated genes result in chromosomal translocations, which is the basis of genetic mapping.
Abstract: We have examined meiotic and mitotic recombination between repeated genes on nonhomologous chromosomes in the yeast Saccharomyces cerevisiae. The results of these experiments can be summarized in three statements. First, gene conversion events between repeats on nonhomologous chromosomes occur frequently in meiosis. The frequency of such conversion events is only 17-fold less than the analogous frequency of conversion between genes at allelic positions on homologous chromosomes. Second, meiotic and mitotic conversion events between repeated genes on nonhomologous chromosomes are associated with reciprocal recombination to the same extent as conversion between allelic sequences. The reciprocal exchanges between the repeated genes result in chromosomal translocations. Finally, recombination between repeated genes on nonhomologous chromosomes occurs much more frequently in meiosis than in mitosis. ECOMBINATION in eukaryotic organisms occurs in mitosis and meiosis R and may be either a reciprocal or nonreciprocal event. Reciprocal recombination changes the linkage relationships of genes along a chromosome and is the basis of genetic mapping. In those organisms in which all four products of a single meiotic division can be analyzed, nonreciprocal recombination or gene conversion is signaled by a 3:l segregation pattern of allelic sequences instead of the normal 2:2 segregation pattern. In fungi, reciprocal and nonreciprocal recombination are associated with one another so that, on the average, a gene conversion event at a given locus is accompanied by a reciprocal exchange event approximately half of the time (reviewed by ORR-WEAVER and SZOSTAK 1985). These conversion-associated reciprocal exchanges are usually detected by examining genetic markers that flank the site of the conversion event. The association of reciprocal and nonreciprocal recombination has been interpreted to mean that the two processes are mechanistically related to one another, and this notion has been incorporated into all current models of genetic recombination (MESELSON and RADDING 1975; SZOSTAK et al. 1983). Although models differ in the method of initiating a recombination event, all
4 citations