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Insertion site preferences of the P transposable element in Drosophila melanogaster.

ABSTRACT: We determined the genomic sequence at the site of insertion in 2,266 unselected P element insertion events. Estimating physical properties of the genomic DNA at these insertion sites-such as base composition, bendability, A-philicity, protein-induced deformability, and B-DNA twist-revealed that they differ significantly from average chromosomal DNA. By examining potential hydrogen bonding sites in the major groove, we identified a 14-bp palindromic pattern centered on the 8-bp target site duplication that is generated by P element insertion. Our results suggest that the P-element transposition mechanism has a two-fold dyad symmetry and recognizes a structural feature at insertion sites, rather than a specific sequence motif.

SUBMITTER: Liao GC

PROVIDER: S-EPMC16242 | biostudies-literature | 2000 Mar

REPOSITORIES: biostudies-literature

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Insertion site preferences of the P transposable element in Drosophila melanogaster.

Liao G C GC Rehm E J EJ Rubin G M GM

Proceedings of the National Academy of Sciences of the United States of America 20000301 7

We determined the genomic sequence at the site of insertion in 2,266 unselected P element insertion events. Estimating physical properties of the genomic DNA at these insertion sites-such as base composition, bendability, A-philicity, protein-induced deformability, and B-DNA twist-revealed that they differ significantly from average chromosomal DNA. By examining potential hydrogen bonding sites in the major groove, we identified a 14-bp palindromic pattern centered on the 8-bp target site duplic ...[more]

PMID: 10716700

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