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Gene silencing: cosuppression at a distance
1Department of Genetics and Developmental Biology, Monash University, Clayton, Melbourne, Victoria 3168, Australia. david.smyth@sci.monash.edu.au
Current Biology : CB
|February 21, 1998
Summary
Gene silencing, known as cosuppression, can occur in plants when a transgenic gene is introduced. This silencing effect can spread from cell to cell through the plant
Area of Science:
- Plant molecular biology
- Gene regulation
- Transgenic technology
Background:
- Introduction of a transgenic gene can lead to the silencing of both the introduced and the original endogenous gene.
- This phenomenon, termed cosuppression, affects gene expression in plants.
Purpose of the Study:
- To investigate the phenomenon of gene cosuppression in plants.
- To understand the cell-to-cell movement of the silencing signal.
Main Methods:
- Utilizing transgenic plant models carrying endogenous genes.
- Observing gene expression patterns within individual cells and across plant tissues.
Main Results:
- Cosuppression was observed, leading to the silencing of both transgenic and endogenous gene copies.
- Evidence suggests that the silencing effect is not limited to individual cells but can spread to distant cells.
Conclusions:
- Cosuppression is a trans-acting phenomenon in plants, capable of silencing homologous genes.
- A mobile signaling agent, likely moving through the phloem, mediates the spread of gene silencing throughout the plant.
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