Related Experiment Video
Updated: Sep 3, 2025
11:39
Chromatin Immunoprecipitation ChIP in Mouse T-cell Lines
Published on: June 17, 2017
18.5K
Single-Cell Mononucleotide Microsatellite Analysis Reveals Differential Insertion-Deletion Dynamics in Mouse T Cells
Elli-Mari Aska1, Bulat Zagidullin1,2, Esa Pitkänen2,3,4
1Research Program in Systems Oncology, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
Frontiers in Genetics
|July 25, 2022
Summary
Mismatch repair deficiency causes microsatellite instability (MSI). This study reveals deletions are the main MSI type in deficient cells, linked to longer A/T tracts and transcribed genes.
Area of Science:
- Genetics
- Molecular Biology
- Genomics
Background:
- Microsatellites are prone to replication slippage, causing mutations if unrepaired.
- Mismatch repair (MMR) corrects these errors, maintaining microsatellite stability.
- MMR deficiency leads to microsatellite instability (MSI).
Purpose of the Study:
- To investigate the previously unrecognized features of in vivo MSI.
- To analyze mutational dynamics of insertions and deletions in MMR-proficient and -deficient cells.
- To identify factors influencing MSI type and location.
Main Methods:
- Sequencing of single-cell exomes from mouse T cells.
- Comparison of MMR-proficient and MMR-deficient (Mlh1-/-) cells.
- Analysis of microsatellite length, nucleotide composition, gene features, and replication timing.
Main Results:
- Deletions are the predominant MSI type in MMR-deficient cells.
- Deletions are preferentially associated with longer A/T tracts.
- Deletions correlate with long or transcribed genes and later replication timing.
Conclusions:
- MMR deficiency exhibits distinct mutational dynamics for insertions and deletions.
- Specific sequence and genomic features influence the propensity for deletions in MSI.
- Single-cell analysis provides novel insights into in vivo MSI mechanisms.
