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Transient Gene Expression in Tobacco using Gibson Assembly and the Gene Gun
Published on: April 19, 2014
The MAR-Mediated Reduction in Position Effect Can Be Uncoupled from Copy Number-Dependent Expression in Transgenic
L. Mlynarova1, R. C. Jansen, A. J. Conner
1Department of Molecular Biology, Centre for Plant Breeding and Reproduction Research (CPRO-DLO), P.O. Box 16, NL-6700 AA Wageningen, The Netherlands.
The Plant Cell
|May 1, 1995
Summary
Matrix-associated regions (MARs) influence gene expression in plants. While MARs affected NPTII gene expression, they unexpectedly did not reduce its variation, unlike the GUS gene, suggesting dosage compensation for GUS.
Area of Science:
- Plant Molecular Biology
- Epigenetics and Chromatin Structure
- Gene Regulation
Background:
- Matrix-associated regions (MARs) are DNA elements implicated in organizing chromatin into independent domains.
- These domains are hypothesized to ensure position-independent and copy number-dependent gene expression.
- Understanding MAR function is crucial for controlling transgene expression in plants.
Purpose of the Study:
- To investigate the role of MARs in establishing independent chromatin domains in plants.
- To assess the impact of MARs on the expression of two different transgenes (NPTII and GUS) within an artificial domain.
- To determine if MARs confer copy number-dependent expression and reduce expression variation.
Main Methods:
- Cloning of two transgenes, NPTII and GUS, between chicken lysozyme A elements (MARs).
- Integration of these constructs into plant DNA to create artificial chromatin domains.
- Analysis of transgene expression levels and variation in transformed tobacco plants.
Main Results:
- MARs increased relative transformation efficiency for the NPTII gene.
- MARs significantly reduced variation in GUS gene expression, as expected.
- Contrary to expectations, GUS gene expression was not copy number-dependent, showing dosage compensation.
Conclusions:
- MARs influence transgene expression and transformation efficiency in plants.
- The dCaMV 35S promoter driving GUS expression appears subject to dosage compensation in mature tobacco plants.
- Topological interactions may affect MAR function as domain boundaries, impacting gene expression patterns.
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