Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1993 Jan;36(1):9-20.
doi: 10.1007/BF02407302.

The evolution of long interspersed repeated DNA (L1, LINE 1) as revealed by the analysis of an ancient rodent L1 DNA family

Affiliations

The evolution of long interspersed repeated DNA (L1, LINE 1) as revealed by the analysis of an ancient rodent L1 DNA family

E Pascale et al. J Mol Evol. 1993 Jan.

Abstract

All modern mammals contain a distinctive, highly repeated (> or = 50,000 members) family of long interspersed repeated DNA called the L1 (LINE 1) family. While the modern L1 families were derived from a common ancestor that predated the mammalian radiation approximately 80 million years ago, most of the members of these families were generated within the last 5 million years. However, recently we demonstrated that modern murine (Old World rats and mice) genomes share an older long interspersed repeated DNA family that we called Lx. Here we report our analysis of the DNA sequence of Lx family members and the relationship of this family to the modern L1 families in mouse and rat. The extent of DNA sequence divergence between Lx members indicates that the Lx amplification occurred about 12 million years ago, around the time of the murine radiation. Parsimony analysis revealed that Lx elements were ancestral to both the modern rat and mouse L1 families. However, we found that few if any of the evolutionary intermediates between the Lx and the modern L1 families were extensively amplified. Because the modern L1 families have evolved under selective pressure, the evolutionary intermediates must have been capable of replication. Therefore, replication-competent L1 elements can reside in genomes without undergoing extensive amplification. We discuss the bearing of our findings on the evolution of L1 DNA elements and the mammalian genome.

PubMed Disclaimer

References

    1. Gene. 1986;42(1):119-23 - PubMed
    1. J Mol Evol. 1987;26(3):180-6 - PubMed
    1. Nucleic Acids Res. 1991 May 11;19(9):2497 - PubMed
    1. Mol Cell Biol. 1990 Dec;10(12):6718-29 - PubMed
    1. J Mol Evol. 1984;21(1):58-71 - PubMed

LinkOut - more resources