Related Experiment Video
Updated: May 8, 2026
07:48
Use of Time-Lapse Microscopy and Stage-Specific Nuclear Depletion of Proteins to Study Meiosis in S. cerevisiae
Published on: October 11, 2022
Global linkage map connects meiotic centromere function to chromosome size in budding yeast
Anastasia Baryshnikova1, Benjamin VanderSluis, Michael Costanzo
1Banting and Best Department of Medical Research, The Donnelly Center for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario M5S 3E1, Canada.
G3 (Bethesda, Md.)
|August 28, 2013
Summary
Synthetic genetic array (SGA) analysis now maps meiotic recombination. This method uses double-mutant colony sizes to create a high-resolution genetic linkage map, revealing insights into chromosome segregation fidelity.
Area of Science:
- Genetics
- Molecular Biology
- Yeast Genetics
Background:
- Synthetic genetic array (SGA) analysis automates yeast genetics for high-throughput double mutant construction.
- Quantitative colony sizes in SGA analysis measure cellular fitness and genetic interactions like synthetic lethality.
Purpose of the Study:
- To demonstrate that SGA colony sizes can be leveraged for genome-wide mapping of meiotic recombination.
- To construct a high-resolution genetic linkage map using quantitative SGA data.
Main Methods:
- Utilized quantitative colony size data from approximately 1.2 million double mutants on the same chromosome.
- Applied SGA analysis to generate a genome-scale genetic linkage map with a resolution of approximately 5 kb.
Main Results:
- Generated a reproducible and consistent genetic linkage map aligning with previous meiotic recombination studies.
- Confirmed a linear relationship between chromosome size and the total number of crossovers per chromosome.
- Discovered a correlation between chromosome size, pericentromere linkage region size, cohesin loading, and DNA double-strand break frequency.
Conclusions:
- Chromosome size appears to play a direct role in regulating the fidelity of chromosome segregation during meiosis.
- Findings suggest mechanisms for balancing crossover distribution to prevent aneuploidy.
Related Concept Videos
02:02Meiosis 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,...
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,...
01:57Meiosis II
Meiosis II is the second and final stage of meiosis. It relies on the haploid cells produced during meiosis I, each of which contain only 23 chromosomes—one from each homologous initial pair. Importantly, each chromosome in these cells is composed of two joined copies, and when these cells enter meiosis II, the goal is to separate such sister chromatids using the same microtubule-based network employed in other division processes. The result of meiosis II is two haploid cells, each containing...
02:30Histone Variants at the Centromere
Histone variants are the histone proteins with structural and sequence variations. These variants may be regarded as “mutant” forms that replace their canonical histone counterparts in the nucleosomes. Specific post-translational modifications on the histone variants enable further chromatin complexity and regulate tissue-specific gene expression. The most common histone variants are from histone H2A, H2B, and linker histone H1 families. However, several variants of histone H3 variants are also...
02:57Attachment of Sister Chromatids
As cells progress into mitosis, the nuclear envelope breaks down, and the condensed chromosomes are exposed to the array of bipolar microtubules of the mitotic spindle. The kinetochore, a large, disc-shaped protein complex, is present at the centromere region of the sister chromatids and acts as a binding site for the microtubules. Usually, the plus-end of a single microtubule is embedded within the kinetochore. However, some kinetochores first establish lateral contact with the side-wall of a...
01:17Karyotyping
Overview
02:11Forces Acting on Chromosomes
During mitosis, chromosome movements occur through the interplay of multiple piconewton level forces. In prometaphase, these forces help in chromosome assembly or congression at the equatorial plane, eventually leading to their alignment at the metaphase plate. The forces acting on the chromosomes are space and time-dependent; therefore, they vary with the position of the chromosomes as the cell progresses through mitosis.
Microtubules and motor proteins exert two types of forces on...
Microtubules and motor proteins exert two types of forces on...