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Updated: May 20, 2026
10:18
Agrobacterium-Mediated Virus-Induced Gene Silencing Assay In Cotton
Published on: August 20, 2011
Duplicate gene evolution, homoeologous recombination, and transcriptome characterization in allopolyploid cotton
Lex E Flagel1, Jonathan F Wendel, Joshua A Udall
1Department of Biology, Duke University, Durham, NC 27708, USA.
BMC Genomics
|July 10, 2012
Summary
Polyploidy in cotton accelerated gene evolution and led to significant genetic exchange between duplicate genomes. This study reveals key insights into the evolutionary consequences of polyploidy in plants.
Area of Science:
- Plant genomics
- Evolutionary biology
- Molecular genetics
Background:
- Modern allotetraploid cotton genomes (A and D) originated from polyploidy ~1-2 million years ago.
- Comparing diploid and allotetraploid cottons aids evolutionary inferences about polyploidy.
- This study presents a comprehensive expressed sequence tag (EST) assembly from diploid and allotetraploid cottons.
Purpose of the Study:
- To infer genic evolution in cotton using EST data.
- To characterize functional and mutational properties of the cotton transcriptome.
- To build a genome-specific single nucleotide polymorphism (SNP) database.
Main Methods:
- Generated millions of Sanger and next-generation sequencing reads (ESTs).
- Aligned ESTs to infer genome-specific SNPs.
- Conducted molecular evolutionary analyses on protein-coding regions.
Main Results:
- Inferred 259,192 genome-specific SNPs.
- Observed increased nucleotide substitution rates in allotetraploid genomes compared to diploids.
- Detected non-independent evolution in ~7% of duplicate genes, indicating nonreciprocal homoeologous recombination (NRHR).
Conclusions:
- Cotton genes show accelerated molecular evolution post-polyploidy.
- Polyploidy facilitates significant nonreciprocal exchange between homoeologous genes.
- Findings impact understanding of polyploidy consequences and duplicate gene evolution.
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