[Chromosome stability in saccharomycete yeasts]
Genetika
|December 1, 1987
Summary
UV-induced yeast mutants show chromosome instability. Two specific mutants, CL4 and CL8, exhibit unstable chromosome maintenance and mini-chromosome instability, suggesting defects in centromere function.
Area of Science:
- Genetics
- Molecular Biology
- Cell Biology
Background:
- Chromosome instability is a hallmark of many diseases.
- Understanding the mechanisms of chromosome stability is crucial for cell biology.
- Yeast models are valuable for studying fundamental genetic processes.
Purpose of the Study:
- To identify and characterize yeast mutants with high chromosome instability.
- To investigate the genetic basis of chromosome III instability.
- To explore the role of replication and centromere function in chromosome stability.
Main Methods:
- UV irradiation of yeast strain Z4221-3c1.
- Isolation and classification of chromosome loss (Chl+) mutants.
- Analysis of mitotic recombination frequencies.
- Testing mini-chromosome stability with varying replicators and centromeric loci.
- Genetic analysis to identify responsible genes.
Main Results:
- Two classes of Chl+ mutants were identified: one with increased recombination and another (CL4, CL8) with chromosome instability but normal recombination.
- Mutants CL4 and CL8 showed instability of artificial mini-chromosomes.
- Mini-chromosome stability in CL4 and CL8 was independent of ARS1 replicator type or homologous replicators from Candida maltosa.
- The instability in CL4 and CL8 is controlled by two nonallelic genes, chl14 and chl18.
Conclusions:
- Mutants CL4 and CL8 possess distinct mechanisms of chromosome instability.
- The identified genes chl14 and chl18 likely play a role in centromere-spindle microtubule interactions.
- These findings contribute to understanding the regulation of chromosome segregation and stability.
