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Scalable Transfection of Maize Mesophyll Protoplasts
Published on: June 23, 2023
Transcriptional activity of transposable elements in maize
1Departament of Molecular Genetics, Centre for Research in Agricultural Genomics, CSIC (IRTA-UAB), Jordi Girona, 18, 08034 Barcelona, Spain. cvsgmp@cid.csic.es
BMC Genomics
|October 27, 2010
Summary
Maize transposable elements show variable transcriptional activity across tissues, with gypsy-like retrotransposons being highly active. This suggests potential regulation at post-transcriptional levels, impacting transposition frequency.
Area of Science:
- Genomics
- Molecular Biology
- Plant Science
Background:
- Mobile genetic elements, particularly transposable elements (TEs), constitute a significant portion of eukaryotic genomes.
- In maize, TEs comprise approximately 85% of the genome, yet their transcriptional regulation remains poorly understood.
- Maize boasts extensive expressed sequence tag (EST) databases, offering a valuable resource for studying TE transcription.
Purpose of the Study:
- To investigate the transcriptional activity of 56 maize transposable element families.
- To analyze TE expression patterns across different maize organs using EST data.
- To understand the regulation of transposable element transcription in maize.
Main Methods:
- Systematic search of over two million maize expressed sequence tags (ESTs).
- Analysis of sequence similarity between ESTs and transposable elements.
- Comparison of transcriptional activity across 56 TE families and different maize tissues.
Main Results:
- At least 1.5% of maize ESTs exhibit sequence similarity to transposable elements.
- TE family expression patterns are highly variable, even within the same class.
- Gypsy-like retrotransposons generally show higher transcriptional activity than other TE classes.
- Transcriptional activity is particularly elevated in shoot apical meristem and sperm cells.
- Sequence comparisons indicate that only a small fraction of TE copies are transcriptionally active.
Conclusions:
- High-throughput sequencing methodologies enable the characterization of repetitive element transcription in maize.
- Considerable transcriptional activity of certain TE families in specific tissues suggests either frequent transposition or post-transcriptional control mechanisms.
- Further research is needed to fully elucidate the regulatory networks governing TE transcription and transposition in maize.
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