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Updated: Oct 20, 2026

Analysis of LINE-1 Retrotransposition at the Single Nucleus Level
11:52

Analysis of LINE-1 Retrotransposition at the Single Nucleus Level

Published on: April 23, 2016

Structural features of mag, a gypsy-like retrotransposon of Bombyx mori, with unusual short terminal repeats

A Garel1, P Nony, J C Prudhomme

  • 1Université Claude Bernard, Lyon 1, Centre de Génétique Moléculaire et Cellulaire, UMR 106, Villeurbanne, France.

Genetica
|January 1, 1994
PubMed

Insights

Mag is a retrotransposon inserted into the Sericin 2 gene in Bombyx mori and Bombyx mandarina. This gypsy group element contains genes for key retroviral enzymes, suggesting its potential for genomic activity.

Area of Science:

  • Genetics
  • Molecular Biology
  • Bioinformatics

Background:

  • The Sericin 2 gene in Bombyx mori harbors an insert known as Mag, a type of retrotransposon.
  • Mag elements are found in multiple copies (4-15) dispersed across the genomes of Bombyx mori and Bombyx mandarina.

Purpose of the Study:

  • To characterize the Mag retrotransposon, including its structure and potential functions.
  • To determine the phylogenetic placement of Mag within the retrotransposon family.

Main Methods:

  • Sequence analysis of the Mag element and its flanking regions.
  • Identification and analysis of open reading frames (ORFs) within Mag.
  • Comparative sequence analysis of Mag-encoded proteins with known retrotransposons.

Main Results:

  • Mag is flanked by a 5 bp target sequence and 77-nucleotide direct terminal repeats, containing necessary signals for transcription and reverse transcription.
  • Mag possesses two overlapping ORFs encoding putative nucleic acid binding peptide, protease, reverse transcriptase, RNase H, and endonuclease.
  • Sequence comparisons place Mag within the gypsy group of LTR retrotransposons, closely related to the echinoderm element SURL.

Conclusions:

  • Mag represents a functional LTR retrotransposon within the gypsy group, potentially capable of retrotransposition.
  • The presence of Mag in both Bombyx mori and Bombyx mandarina suggests its ancient origin and conservation.

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