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Manipulation of Ploidy in Caenorhabditis elegans
Published on: March 15, 2018
Rapid evolution of simple sequence repeat induced by allopolyploidization.
Zongxiang Tang1, Shulan Fu, Zhenglong Ren
1State Key Laboratory of Plant Breeding and Genetics, Sichuan Agriculture University, Ya'an, Sichuan 625014, China. zxtang@sicau.edu.cn
Journal of Molecular Evolution
|August 19, 2009
Summary
Allopolyploidization, a process of genome doubling, can induce microsatellite evolution in plants. This study provides experimental evidence showing changes in simple sequence repeat (SSR) lengths after allopolyploidization in wheat and rye hybrids.
Area of Science:
- Genetics
- Plant Biology
- Molecular Evolution
Background:
- Microsatellite evolution is typically studied in diploid organisms.
- Direct experimental evidence for microsatellite evolution post-allopolyploidization has been limited.
- Allopolyploidization involves genome doubling and can lead to genetic instability.
Purpose of the Study:
- To investigate microsatellite evolution following allopolyploidization.
- To provide direct experimental evidence for changes in simple sequence repeats (SSRs) after genome doubling.
- To understand the mechanisms driving SSR variation in newly synthesized allopolyploids.
Main Methods:
- Synthesized allopolyploids from Triticum aestivum and Secale cereale.
- Utilized 163 wheat simple sequence repeat (SSR) markers to analyze genetic variation.
- Observed PCR product variation and sequenced altered SSR loci in parental, hybrid, and allopolyploid lines.
Main Results:
- Variation in PCR product length was observed for 29 out of 163 SSR markers.
- 15 SSR markers failed to produce products in amphiploids, while 14 showed length variations.
- Sequencing revealed that length variations in SSRs were primarily due to changes in the number of repeat units, consistent with the slipped-strand mispairing model.
Conclusions:
- Allopolyploidization stress can induce microsatellite evolution.
- Changes in repeat unit number are a major driver of SSR length variation after allopolyploidization.
- This study offers a clear example of SSR evolution in the context of allopolyploidization.
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