Related Experiment Video

Updated: Aug 2, 2026

Combining Magnetic Sorting of Mother Cells and Fluctuation Tests to Analyze Genome Instability During Mitotic Cell Aging in Saccharomyces cerevisiae
11:08

Combining Magnetic Sorting of Mother Cells and Fluctuation Tests to Analyze Genome Instability During Mitotic Cell Aging in Saccharomyces cerevisiae

Published on: October 16, 2014

Increased spontaneous mitotic segregation in MMS-sensitive mutants of Saccharomyces cerevisiae

S Prakash, L Prakash

    Genetics
    |October 1, 1977
    PubMed

    Insights

    Methyl methanesulfonate (MMS)-sensitive yeast mutants significantly elevate spontaneous mitotic segregation rates. These findings highlight MMS sensitivity as a key indicator of DNA repair defects impacting genetic stability.

    Area of Science:

    • Molecular Biology
    • Genetics
    • Yeast Genetics

    Background:

    • DNA repair mechanisms are crucial for maintaining genomic integrity.
    • Methyl methanesulfonate (MMS) is a chemical mutagen used to study DNA damage response pathways.
    • Spontaneous mitotic segregation is a measure of genetic instability in yeast.

    Purpose of the Study:

    • To investigate the role of MMS sensitivity in spontaneous mitotic segregation.
    • To characterize novel MMS-sensitive mutants in Saccharomyces cerevisiae.
    • To quantify the impact of specific mutations on genetic instability.

    Main Methods:

    • Utilized Saccharomyces cerevisiae as a model organism.
    • Generated and analyzed homozygous MMS-sensitive mutants.
    • Assessed spontaneous mitotic segregation rates to canavanine resistance in heterozygous diploids.
    • Determined sensitivity to MMS, X-rays, and UV radiation for characterized mutants.

    Main Results:

    • Four complementation groups of MMS-sensitive mutants were identified.
    • Homozygous mutants exhibited a 13- to 170-fold increase in spontaneous mitotic segregation rates.
    • The mms8-1 mutant showed the highest increase (170-fold) and sensitivity to MMS and X-rays.
    • Other mutants (mms9-1, mms13-1, mms21-1) displayed varying sensitivities and segregation rates.

    Conclusions:

    • MMS sensitivity in yeast is strongly correlated with increased rates of spontaneous mitotic segregation.
    • Specific MMS-sensitive mutations confer distinct sensitivities to different DNA damaging agents.
    • These mutants provide valuable tools for dissecting DNA repair pathways and understanding genetic instability.

    More Related Videos

    Use of Time-Lapse Microscopy and Stage-Specific Nuclear Depletion of Proteins to Study Meiosis in S. cerevisiae07:48

    Use of Time-Lapse Microscopy and Stage-Specific Nuclear Depletion of Proteins to Study Meiosis in S. cerevisiae

    Published on: October 11, 2022

    Manipulation and Analysis of Cell Cycle-Dependent Processes in Budding Yeast08:13

    Manipulation and Analysis of Cell Cycle-Dependent Processes in Budding Yeast

    Published on: September 26, 2025

    Related Concept Videos

    Separation of Sister Chromatids02:17

    Separation of Sister Chromatids

    At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
    At the onset of anaphase, separase, a proteolytic enzyme, is...
    The Spindle Assembly Checkpoint02:19

    The Spindle Assembly Checkpoint

    The spindle assembly checkpoint is a molecular surveillance mechanism ensuring the fidelity of chromosome segregation during anaphase. The checkpoint monitors the completion of all the prerequisite steps before chromosome segregation to determine whether the segregation process should proceed or be delayed.
    Many proteins function together to control the spindle assembly checkpoint. Mutations affecting these proteins may allow cells to proceed into anaphase prematurely, resulting in the...
    Meiosis II02:02

    Meiosis II

    Meiosis II entails cell division and segregation of the sister chromatids, resulting in the production of four unique haploid gametes. The steps for meiosis II are similar to mitosis, except that meiosis II occurs in haploid cells, whereas mitosis occurs in diploid cells.
    The timing and cell division patterns of meiosis differ between males and females. In male meiosis, the centrosomes are part of the formation of the meiotic spindle. However, in oocytes, including that of humans, Drosophila,...
    Meiosis vs. Mitosis02:57

    Meiosis vs. Mitosis

    Cell division is necessary for growth and reproduction in organisms. Mitosis aids cell growth and development by dividing somatic cells. In contrast, meiosis causes the division of germ cells and plays an essential role in sexual reproduction. Due to their unique functional requirements, mitosis and meiosis differ from each other in multiple aspects.
    Before the start of mitosis and meiosis I, the cell synthesizes DNA, resulting in two homologous copies of each chromosome. DNA synthesis is...