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Agrobacterium-Mediated Immature Embryo Transformation of Recalcitrant Maize Inbred Lines Using Morphogenic Genes
Published on: February 14, 2020
Macrotransposition and other complex chromosomal restructuring in maize by closely linked transposons in direct
1Waksman Institute, Rutgers University, Piscataway, New Jersey 08854, USA.
The Plant Cell
|August 19, 2008
Summary
Closely linked transposable elements (TEs) in maize can excise and reinsert as a unit, forming macrotransposons. This process, along with other rearrangements, highlights TEs
Area of Science:
- Genetics and Genomics
- Molecular Biology
- Plant Biology
Background:
- Transposable elements (TEs) are mobile DNA sequences that can alter genome structure.
- Pairs of closely linked TEs can interact, leading to complex chromosomal rearrangements.
- Previous hypotheses suggested macrotransposons, but direct evidence of their insertion was lacking.
Purpose of the Study:
- To investigate the transposition of macrotransposons formed by closely linked Ac and Ds elements in maize.
- To characterize the types of chromosomal rearrangements produced by these interacting TEs.
Main Methods:
- Utilized a maize (Zea mays) genetic system with a chromosome-breaking pair of Ac and Ds elements.
- Analyzed heritable chromosomal rearrangements occurring in a non-essential genomic region.
- Observed and documented the excision and reinsertion events of the postulated macrotransposon.
Main Results:
- Demonstrated that the postulated macrotransposon, composed of two linked TEs and intervening DNA, can excise and reinsert elsewhere in the genome.
- Identified other complex rearrangements, including deletions, inversions, and shuffling of the inter-transposon DNA.
- Confirmed the capability of closely linked TE pairs to restructure plant genomes.
Conclusions:
- Closely linked transposable element pairs are significant drivers of genome restructuring.
- The observed macrotransposition mechanism provides a new understanding of how TEs reshape plant genomes.
- These findings have implications for understanding genome evolution and plasticity in plants.
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