A maize cryptic Ac-homologous sequence derived from an Activator transposable element does not transpose.
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.
Leu
J Y
JY
Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.
Sun
Y H
YH
Lai
Y K
YK
Chen
J
J
D001483:Base Sequence; D015139:Blotting, Southern; D003001:Cloning, Molecular; D004251:DNA Transposable Elements / Q000235:genetics*; D008745:Methylation; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D003313:Zea mays / Q000235:genetics*
D004251:DNA Transposable Elements