A retrotransposable element from the mosquito Anopheles gambiae .
A family of middle repetitive elements from the African malaria vector Anopheles gambiae is described. Approximately 100 copies of the element, designated T1Ag, are dispersed in the genome. Full-length elements are 4.6 kilobase pairs in length, but truncation of the 5' end is common. Nucleotide sequences of one full-length, two 5'-truncated, and two 5' ends of T1Ag elements were determined and aligned to define a consensus sequence. Sequence analysis revealed two long, overlapping open reading frames followed by a polyadenylation signal, AATAAA, and a tail consisting of tandem repetitions of the motif TGAAA. No direct or inverted long terminal repeats (LTRs) were detected. The first open reading frame, 442 amino acids in length, includes a domain resembling that of nucleic acid-binding proteins. The second open reading frame, 975 amino acids long, resembles the reverse transcriptases of a category of retrotransposable elements without LTRs, variously termed class II retrotransposons, class III elements or non-LTR retrotransposons. Similarity at the sequence and structural levels places T1Ag in this category.
Besansky
N J
NJ
Department of Biology, Yale University, New Haven, Connecticut 06511.
D000595:Amino Acid Sequence; D000818:Animals; D000852:Anopheles / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D004251:DNA Transposable Elements; D008969:Molecular Sequence Data; D012194:RNA-Directed DNA Polymerase / Q000235:genetics; D012091:Repetitive Sequences, Nucleic Acid; D015183:Restriction Mapping
D004251:DNA Transposable Elements; D012194:RNA-Directed DNA Polymerase