Tto1, a Ty1/Copia-like LTR retrotransposon described in Nicotiana tabacum (Hirochika et al. 1996). This element belongs to the Tork clade within Branch 2 of the Ty1/Copia family (Llorens et al. 2009). Its genome is 5300 bp in size, including two identical LTRs of 574 bp long. The LTRs flanked internal region encodes for a single Open Reading Frame (ORF) of 1338 amino acids with the typical gag and pol structure: gag, protease, integrase, reverse transcriptase and ribonuclease H (Hirochika et al. 1996).
Figure not to scale. If present, long terminal repeats (LTRs) have been highlighted in blue. Amino acid motifs noted with lines indicate the conserved residues in each protein domain, abbreviations below mean:
||DU or DUT=dUTPase
||TAV or IBMP=transactivator/viroplasmin or inclusion body matrix protein
||PBS=primer binding site
||ATF=aphid transmission factor
||VAP=virion associated protein