The Fortuitous Cloning of Retroelement-Like Sequences from Wheat and Rye as By-Products of a Specific Polymerase Chain Reaction

Abstract

Cloning of by-products of a specific PCR reaction, directed to the Em genes of wheat and rye, has resulted in the identification of ten sequences with homology to the known Tyl-copia-like retroelements WIS 2–1A from wheat and BARE-1 from barley. These sequences were amplified by only one of the primers due to the presence of an inverted repeat. Nine sequences are ca. 740 bp long and contain part of the left LTR, the adjacent primer-binding site and part of the leader sequence, whereas one shorter sequence (535 bp) consists of part of the leader sequence only. The dendrogram, constructed from the multiple sequence alignment, classified the isolated sequences into two narrowly related groups that belong to the WIS-2 family of cereal retroelements.

Key Words:

• Triticum aestivum
• Secale cereale
• co-amplification
• retrotransposon-like element
• repetitive DNA