scholarly journals Genetic mapping of Ty elements in Saccharomyces cerevisiae.

1984 ◽  
Vol 4 (2) ◽  
pp. 329-339 ◽  
Author(s):  
H L Klein ◽  
T D Petes
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Statistical Analysis ◽  
Genetic Mapping ◽  
Transposable Element ◽  
Genetic Map ◽  
Selectable Marker ◽  
Repeated Element ◽  
Ty Elements ◽  
Reciprocal Exchange ◽  
Leu2 Gene

We used transformation to insert a selectable marker at various sites in the Saccharomyces cerevisiae genome occupied by the transposable element Ty. The vector CV9 contains the LEU2+ gene and a portion of the repeated element Ty1-17. Transformation with this plasmid resulted in integration of the vector via a reciprocal exchange using homology at the LEU2 locus or at the various Ty elements that are dispersed throughout the S. cerevisiae genome. These transformants were used to map genetically sites of several Ty elements. The 24 transformants recovered at Ty sites define 19 distinct loci. Seven of these were placed on the genetic map. Two classes of Ty elements were identified in these experiments: a Ty1-17 class and Ty elements different from Ty1-17. Statistical analysis of the number of transformants at each class of Ty elements shows that there is preferential integration of the CV9 plasmid into the Ty1-17 class.

Genetic mapping of Ty elements in Saccharomyces cerevisiae

1984 ◽  
Vol 4 (2) ◽  
pp. 329-339
Author(s):  
H L Klein ◽  
T D Petes
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Statistical Analysis ◽  
Genetic Mapping ◽  
Transposable Element ◽  
Genetic Map ◽  
Selectable Marker ◽  
Repeated Element ◽  
Ty Elements ◽  
Reciprocal Exchange ◽  
Leu2 Gene

We used transformation to insert a selectable marker at various sites in the Saccharomyces cerevisiae genome occupied by the transposable element Ty. The vector CV9 contains the LEU2+ gene and a portion of the repeated element Ty1-17. Transformation with this plasmid resulted in integration of the vector via a reciprocal exchange using homology at the LEU2 locus or at the various Ty elements that are dispersed throughout the S. cerevisiae genome. These transformants were used to map genetically sites of several Ty elements. The 24 transformants recovered at Ty sites define 19 distinct loci. Seven of these were placed on the genetic map. Two classes of Ty elements were identified in these experiments: a Ty1-17 class and Ty elements different from Ty1-17. Statistical analysis of the number of transformants at each class of Ty elements shows that there is preferential integration of the CV9 plasmid into the Ty1-17 class.

Meiotic recombination between repeated transposable elements in Saccharomyces cerevisiae

1988 ◽  
Vol 8 (7) ◽  
pp. 2942-2954
Author(s):  
M Kupiec ◽  
T D Petes
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Transposable Elements ◽  
Gene Conversion ◽  
Meiotic Recombination ◽  
Small Region ◽  
Ty Elements ◽  
Ty Element ◽  
Reciprocal Exchange ◽  
Gene Conversions ◽  
Conversion Tract

We have measured the frequency of meiotic recombination between marked Ty elements in the Saccharomyces cerevisiae genome. These recombination events were usually nonreciprocal (gene conversions) and sometimes involved nonhomologous chromosomes. The frequency of ectopic gene conversion among Ty elements appeared lower than expected on the basis of previous studies of recombination between artificially constructed repeats. The conversion events involved either a subset of the total Ty elements in the genome or the conversion tract was restricted to a small region of the Ty element. In addition, the observed conversion events were very infrequently associated with reciprocal exchange.

scholarly journals Genetic Mapping Reveals that Sinefungin Resistance in Toxoplasma gondii Is Controlled by a Putative Amino Acid Transporter Locus That Can Be Used as a Negative Selectable Marker

2014 ◽  
Vol 14 (2) ◽  
pp. 140-148 ◽  
Author(s):  
Michael S. Behnke ◽  
Asis Khan ◽  
L. David Sibley
Keyword(s):  
Toxoplasma Gondii ◽  
Genetic Mapping ◽  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Genetic Map ◽  
Selectable Marker ◽  
Stop Codon ◽  
Whole Genome ◽  
Content Type ◽  
Negative Selectable Marker

ABSTRACTQuantitative trait locus (QTL) mapping studies have been integral in identifying and understanding virulence mechanisms in the parasiteToxoplasma gondii. In this study, we interrogated a different phenotype by mapping sinefungin (SNF) resistance in the genetic cross between type 2 ME49-FUDRrand type 10 VAND-SNFr. The genetic map of this cross was generated by whole-genome sequencing of the progeny and subsequent identification of single nucleotide polymorphisms (SNPs) inherited from the parents. Based on this high-density genetic map, we were able to pinpoint the sinefungin resistance phenotype to one significant locus on chromosome IX. Within this locus, a single nonsynonymous SNP (nsSNP) resulting in an early stop codon in the TGVAND_290860 gene was identified, occurring only in the sinefungin-resistant progeny. Using CRISPR/CAS9, we were able to confirm that targeted disruption of TGVAND_290860 renders parasites sinefungin resistant. Because disruption of theSNR1gene confers resistance, we also show that it can be used as a negative selectable marker to insert either a positive drug selection cassette or a heterologous reporter. These data demonstrate the power of combining classical genetic mapping, whole-genome sequencing, and CRISPR-mediated gene disruption for combined forward and reverse genetic strategies inT. gondii.

scholarly journals MAPPING CHROMOSOMAL GENES OF SACCHAROMYCES CEREVISIAE USING AN IMPROVED GENETIC MAPPING METHOD

Genetics ◽  
1979 ◽  
Vol 92 (3) ◽  
pp. 803-821
Author(s):  
Reed B Wickner
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Genetic Mapping ◽  
Rapid Method ◽  
Genetic Map ◽  
Mapping Method ◽  
Single Chromosome ◽  
Meiotic Analysis ◽  
Chromosomal Genes ◽  
Killer Plasmid ◽  
Standard Marker

ABSTRACT A triploid (3n) strain of Saccharomyces cereuisiae was constructed carrying a standard marker on each of chromosomes I through XVII in the ——/+J+ configuration. This is called a "supertriploid." Meiotic spores from this strain (n + ∼ n/2) were mated with a haploid (n) carrying an unmapped mutation. Meiotic analysis of each zygote clone (2n + ∼ n/2) produced in this way resulted in elimination of an average of 4.2 chromosomes as the possible location of the unmapped marker. The distribution of extra chromosomes in the 2n + ∼ n/2) strains was nearly random. Meiotic segregrants of these crosses carrying the unmapped mutation in the -/+ configuration were then crossed with multiply marked haploid strains to further narrow the possible location of the unmapped mutation to a single chromosome. Scoring of markers by complemention tests was simplified by mating spore clones with mixtures of a and α strains, each pair carrying the same set of markers. Using this new, more rapid method ("supertriploid mapping"), eight genes required for the maintenance of the killer plasmid were located on the genetic map of S. cerevisiae.

scholarly journals Meiotic recombination between repeated transposable elements in Saccharomyces cerevisiae.

1988 ◽  
Vol 8 (7) ◽  
pp. 2942-2954 ◽  
Author(s):  
M Kupiec ◽  
T D Petes
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Transposable Elements ◽  
Gene Conversion ◽  
Meiotic Recombination ◽  
Small Region ◽  
Ty Elements ◽  
Ty Element ◽  
Reciprocal Exchange ◽  
Gene Conversions ◽  
Conversion Tract

We have measured the frequency of meiotic recombination between marked Ty elements in the Saccharomyces cerevisiae genome. These recombination events were usually nonreciprocal (gene conversions) and sometimes involved nonhomologous chromosomes. The frequency of ectopic gene conversion among Ty elements appeared lower than expected on the basis of previous studies of recombination between artificially constructed repeats. The conversion events involved either a subset of the total Ty elements in the genome or the conversion tract was restricted to a small region of the Ty element. In addition, the observed conversion events were very infrequently associated with reciprocal exchange.

Genetic map of Saccharomyces cerevisiae.

1980 ◽  
Vol 44 (4) ◽  
pp. 519-571 ◽  
Author(s):  
R K Mortimer ◽  
D Schild
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Genetic Map

scholarly journals Tempo and Mode of Ty Element Evolution in Saccharomyces cerevisiae

Genetics ◽  
1999 ◽  
Vol 151 (4) ◽  
pp. 1341-1351 ◽  
Author(s):  
I King Jordan ◽  
John F McDonald
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Negative Selection ◽  
Sequence Variation ◽  
Size Variation ◽  
Sequence Comparisons ◽  
Ty Elements ◽  
Ty Element ◽  
Amino Acid Sequence Variation ◽  
Element Evolution ◽  
High Level

Abstract The Saccharomyces cerevisiae genome contains five families of long terminal repeat (LTR) retrotransposons, Ty1–Ty5. The sequencing of the S. cerevisiae genome provides an unprecedented opportunity to examine the patterns of molecular variation existing among the entire genomic complement of Ty retrotransposons. We report the results of an analysis of the nucleotide and amino acid sequence variation within and between the five Ty element families of the S. cerevisiae genome. Our results indicate that individual Ty element families tend to be highly homogenous in both sequence and size variation. Comparisons of within-element 5′ and 3′ LTR sequences indicate that the vast majority of Ty elements have recently transposed. Furthermore, intrafamily Ty sequence comparisons reveal the action of negative selection on Ty element coding sequences. These results taken together suggest that there is a high level of genomic turnover of S. cerevisiae Ty elements, which is presumably in response to selective pressure to escape host-mediated repression and elimination mechanisms.

scholarly journals Recombination of Ty elements in yeast can be induced by a double-strand break.

Genetics ◽  
1995 ◽  
Vol 140 (1) ◽  
pp. 67-77 ◽  
Author(s):  
A Parket ◽  
O Inbar ◽  
M Kupiec
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
Strand Break ◽  
Double Strand Break ◽  
The Other ◽  
Direct Repeats ◽  
Yeast Saccharomyces Cerevisiae ◽  
Low Frequencies ◽  
Ty Elements ◽  
Main Family

Abstract The Ty retrotransposons are the main family of dispersed repeated sequences in the yeast Saccharomyces cerevisiae. These elements are flanked by a pair of long terminal direct repeats (LTRs). Previous experiments have shown that Ty elements recombine at low frequencies, despite the fact that they are present in 30 copies per genome. This frequency is not highly increased by treatments that cause DNA damage, such as UV irradiation. In this study, we show that it is possible to increase the recombination level of a genetically marked Ty by creating a double-strand break in it. This break is repaired by two competing mechanisms: one of them leaves a single LTR in place of the Ty, and the other is a gene conversion event in which the marked Ty is replaced by an ectopically located one. In a strain in which the marked Ty has only one LTR, the double-strand break is repaired by conversion. We have also measured the efficiency of repair and monitored the progression of the cells through the cell-cycle. We found that in the presence of a double-strand break in the marked Ty, a proportion of the cells is unable to resume growth.

Cloning and genetic mapping of SNF1, a gene required for expression of glucose-repressible genes in Saccharomyces cerevisiae

1984 ◽  
Vol 4 (1) ◽  
pp. 49-53
Author(s):  
J L Celenza ◽  
M Carlson
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Genetic Mapping ◽  
Gene Product ◽  
Structural Gene ◽  
Glucose Repression ◽  
Carbon Sources ◽  
Recombinant Plasmids ◽  
The Right ◽  
Integrating Vector

A functional SNF1 gene product is required to derepress expression of many glucose-repressible genes in Saccharomyces cerevisiae. Strains carrying a snf1 mutation are unable to grow on sucrose, galactose, maltose, melibiose, or nonfermentable carbon sources; utilization of these carbon sources is regulated by glucose repression. The inability of snf1 mutants to utilize sucrose results from failure to derepress expression of the structural gene for invertase at the RNA level. We isolated recombinant plasmids carrying the SNF1 gene by complementation of the snf1 defect in S. cerevisiae. A 3.5-kilobase region is common to the DNA segments cloned in five different plasmids. Transformation of S. cerevisiae with an integrating vector carrying a segment of the cloned DNA resulted in integration of the plasmid at the SNF1 locus. This result indicates that the cloned DNA is homologous to sequences at the SNF1 locus. By mapping a plasmid marker linked to SNF1 in this transformant, we showed that the SNF1 gene is located on chromosome IV. We then mapped snf1 to a position 5.6 centimorgans distal to rna3 on the right arm; snf1 is not extremely closely linked to any previously mapped mutation.

scholarly journals OM MUTATIONS IN DROSOPHILA ANANASSAE ARE LINKED TO INSERTIONS OF A TRANSPOSABLE ELEMENT

Genetics ◽  
1986 ◽  
Vol 114 (1) ◽  
pp. 125-135
Author(s):  
Antony E Shrimpton ◽  
Elizabeth A Montgomery ◽  
Charles H Langley
Keyword(s):  
In Situ Hybridization ◽  
Genetic Mapping ◽  
Transposable Element ◽  
Southern Blotting ◽  
Spontaneous Mutation ◽  
Drosophila Ananassae ◽  
Homologous Region ◽  
Eye Morphology ◽  
Om Mutations

ABSTRACT It has been hypothesized that Om mutability in Drosophila ananassae (involving spontaneous mutation at 20 loci, resulting in semidominant, nonpleiotropic eye morphology defects) was due to insertion of a transposable element, tom. One particularly unstable Χ-linked Om allele produced several derivatives, one of which has a more extreme Om phenotype and was accompanied by a singed bristle mutant, sn9g. DNA probes from the sn locus of D. melanogaster were used to clone the homologous region of D. ananassae. Analysis of sn9g DNA detected a 6.5-kb insert. Genomic Southern blotting and in situ hybridization techniques showed that this insert is repetitive and dispersed. The existence of the tom element is supported by genetic mapping that established homology between the 6.5-kb sn9g insert and Om mutants at the four Χ-linked loci tested.

Sign in / Sign up

Export Citation Format

Share Document