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PubMed · 1320187

A maize cryptic Ac-homologous sequence derived from an Activator transposable element does not transpose.

J Y Leu·Y H Sun·Y K Lai·J Chen
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Abstract

Sequences sharing homology to the transposable element Activator (Ac) are prevalent in the maize genome. A cryptic Ac-like DNA, cAc-11, was isolated from the maize inbred line 4Co63 and sequenced. Cryptic Ac-11 has over 90% homology to known Ac sequences and contains an 11 bp inverted terminal repeat flanked by an 8 bp target site duplication, which are characteristics of Ac and Dissociation (Ds) transposable elements. Unlike the active Ac element, which encodes a transposase, the corresponding sequence in cAc-11 has no significant open reading frame. A 44 bp tandem repeat was found at one end of cAc-11, which might be a result of aberrant transposition. The sequence data suggest that cAc-11 may represent a remnant of an Ac or a Ds element. Sequences homologous to cAc-11 can be detected in many maize inbred lines. In contrast to canonical Ac elements, cAc-11 DNA in the maize genome is hypermethylated and does not transpose even in the presence of an active Ac element.

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Base SequenceBlotting, SouthernCloning, MolecularDNA Transposable ElementsMethylationMolecular Sequence DataPolymerase Chain ReactionRestriction MappingSequence Homology, Nucleic AcidZea maysJournal ArticleResearch Support, Non-U.S. Gov't

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J Y Leu, Y H Sun, Y K Lai, J Chen. 1992. A maize cryptic Ac-homologous sequence derived from an Activator transposable element does not transpose.. https://doi.org/10.1007/bf00265438

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