Abstract.
Repetitive sequences with oligo A tails were observed in Dra1 fragments of Bombyx mori genomic DNA. The full sequence of the element, an abundant non-LTR retrotransposon of B. mori, was determined by assembling inner restriction fragments. This element, designated L1Bm, contained two ORFs encoding a gag-like protein and reverse transcriptase (RT), respectively. An endonuclease domain was identified at the N-terminus of the RT sequence. The homology search of the amino acid sequences revealed that L1Bm belongs evolutionally to the same family as various other non-LTR retrotransposons of Drosophila and Mosquito. On the other hand, L1Bm resembles the L1 element of human genome in its high copy number and its frequent truncation at the 5′-side. Some units of the histone gene repeat in B. mori possess complete L1Bm elements in a 3′-flanking region of H2b.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Received: 26 December 1996 / Accepted: 19 April 1997
Rights and permissions
About this article
Cite this article
Ichimura, S., Mita, K. & Sugaya, K. A Major Non-LTR Retrotransposon of Bombyx mori, L1Bm. J Mol Evol 45, 253–264 (1997). https://doi.org/10.1007/PL00006228
Issue Date:
DOI: https://doi.org/10.1007/PL00006228