Search results for "Saccharomyce"
showing 10 items of 875 documents
Genomic response programs of Saccharomyces cerevisiae following protoplasting and regeneration.
2007
Abstract Global transcription profiling during regeneration of Saccharomyces cerevisiae protoplasts was explored. DNA microarrays measured the expression of 6388 genes and wall removal resulted initially in over-expression of 861 genes that decayed later on, a behaviour expected from a transient stress response. Kinetics of expression divided the genes into 25 clusters. Transcription of the genes from clusters 14–25 was initially up-regulated, suggesting that the grouped genes permitted cell adaptation to the removal of the wall. Clustering of genes involved in “wall structure and biosynthesis” showed that most of them had initially low levels of expression that increased along the process.…
A rapid method for the screening of plasmids in transformed yeast strains
1988
A method for the rapid screening of plasmids in yeast cells has been developed. The method is an adaptation of the currently used alkaline lysis methods forEscherichia coli plasmids. Following the conditions described, several dozen ofSaccharomyces cerevisiae-transformed clones can be analyzed for their plasmid content in less than 2 h. The plasmids obtained by this procedure are suitable for restriction analysis or forE. coli andS. cerevisiae transformation.
Transcriptional and Structural Study of a Region of Two Convergent Overlapping Yeast Genes
1999
The exceptionally close packing of many yeast genes and other chromosomal elements raises the question of how those elements are functionally insulated. All published work shows that natural insulators are very effective, but transcriptional interference (TI) occurs if they are mutated or if their natural context is altered. Mechanisms to avoid TI are poorly understood, but are thought to involve an interplay of cis sequences and trans factors in a chromatin context. We have studied the case of two convergent closely packed ORFs (56 bp of separation) in chromosome IX of Saccharomyces cerevisiae. mRNAs from POT1 and YIL161w overlap by up to 115 nt. Convergent transcription causes a small but…
SRC1: an intron-containing yeast gene involved in sister chromatid segregation
2001
Analysis of a three-member gene family in the yeast Saccharomyces cerevisiae has allowed the discovery of a new gene that comprises two contiguous open reading frames previously annotated as YML034w and YML033w. The gene contains a small intron with two alternative 5′ splicing sites. It is specifically transcribed during G2/M in the cell cycle and after several hours of meiosis induction. Splicing of the mRNA is partially dependent on NAM8 but does not vary during meiosis or the cell cycle. Deletion of the gene induces a shortening of the anaphase and aggravates the phenotype of scc1 and esp1 conditional mutants, which suggests a direct role of the protein in sister chromatid separation. Co…
A novel approach for the improvement of stress resistance in wine yeasts
2006
During wine production yeast cells are affected by several stress conditions that could affect their viability and fermentation efficiency. In this work we describe a novel genetic manipulation strategy designed to improve stress resistance in wine yeasts. This strategy involves modifying the expression of the transcription factor MSN2, which plays an important role in yeast stress responses. The promoter in one of the genomic copies of this gene has been replaced by the promoter of the SPI1 gene, encoding for a cell wall protein of unknown function. SPI1 is expressed at late phases of growth and is regulated by Msn2p. This modification allows self-induction of MSN2 expression. MSN2 gene tr…
Genetic manipulation of HSP26 and YHR087W stress genes may improve fermentative behaviour in wine yeasts under vinification conditions
2008
Throughout wine production yeast cells are affected by a plethora of stress conditions that compromise their ability to carry out the whole process. In recent years important knowledge about the mechanisms involved in stress response in both laboratory and wine yeast strains has been obtained. Several studies have indicated that a correlation exists between stress resistance, expression of stress response genes and fermentative behaviour. In this work we introduce several genetic manipulations in two genes induced by several stress conditions: HSP26 (which encodes a heat shock protein) and YHR087W (encoding a protein of unknown function) in two different wine yeasts, ICV16 and ICV27. These …
Sequencing analysis of a 4·1 kb subtelomeric region from yeast chromosome IV identifiesHXT15, a new member of the hexose transporter family
1996
The DNA sequence of a 4·1 kb region of Saccharomyces cerevisiae chromosome IV was determined. This region contains a single open reading frame which codes for a member of the hexose transporter family. This new gene has been named HXT15 according to yeast gene data bases. The sequence has been entered in the EMBL data library under Accession Number X92891.
Evaluation of different genetic procedures for the generation of artificial hybrids in Saccharomyces genus for winemaking
2012
Several methods based on recombinant DNA techniques have been proposed for yeast strain improvement; however, the most relevant oenological traits depend on a multitude of loci, making these techniques difficult to apply. In this way, hybridization techniques involving two complete genomes became interesting. Natural hybrid strains between different Saccharomyces species have been detected in diverse fermented beverages including wine, cider and beer. These hybrids seem to be better adapted to fluctuating situations typically observed in fermentations due to the acquisition of particular physiological properties of both parental strains. In this work we evaluated the usefulness of three dif…
Identification of yeasts by RFLP analysis of the 5.8S rRNA gene and the two ribosomal internal transcribed spacers
1999
The identification and classification of yeasts have traditionally been based on morphological, physiological and biochemical traits. Various kits have been developed as rapid systems for yeast identification, but mostly for clinical diagnosis. In recent years, different molecular biology techniques have been developed for yeast identification, but there is no available database to identify a large number of species. In the present study, the restriction patterns generated from the region spanning the internal transcribed spacers (ITS1 and ITS2) and the 5.8S rRNA gene were used to identify a total of 132 yeast species belonging to 25 different genera, including teleomorphic and anamorphic a…
Isolation of aCandida albicans gene, tightly linked toURA3, coding for a putative transcription factor that suppresses aSaccharomyces cerevisiaeaft1 …
2001
A pathogen such as C. albicans needs an ef®cient mechanism of iron uptake in an iron- restricted environment such as is the human body. A ferric-reductase activity regulated by iron and copper, and analogous to that in S. cerevisiae, has been described in C. albicans. We have developed an in-plate protocol for the isolation of clones that complement an aft1 mutation in S. cerevisiae that makes cells dependent on iron for growth. After transformation of S. cerevisiae aft1 with a C. albicans library, we have selected clones that grow in conditions of iron de®ciency and share an identical plasmid, pIRO1, with a 4500 bp insert containing the URA3 gene and an ORF (IRO1) responsible for the suppr…