A mouse dispersed repeat sequence showing remarkable similarities to the long terminal repeats of retroviruses.

A mouse 1.3-kb EcoRI dispersed repeat sequence that shows homology by hybridisation to the long terminal repeat of intracisternal A-particle genes has been partially sequenced. One of the established sequence regions shows three major features reminiscent of the long terminal repeats of retroviruses. Firstly, a TATA box precedes a putative capping site (G) by 23 bp. Secondly, the TATA box is itself preceded by the sequence CCTAT. Thirdly, following the capping site, the signal sequence AATAA precedes by 20 bp a possible polyadenylation site (CA). Such a retroviral-like sequence may have been responsible for the initial amplification and dispersion of the mouse repeat family.