L1Resources

This web portal is dedicated to putatively active LINE-1 elements.

What are LINE-1s?

LINE-1 (Long Interspersed Nucleotide Element 1, L1) are the only autonomous retrotransposons in the group
of non-LTR retrotransposons. They comprise about 18%-20% of mammalian genomes.
Click here for background information and literature on LINE-1 elements.

L1Base

L1Base is a dedicated database containing putatively active LINE-1 (L1) insertions residing in human and rodent genomes: a) intact in the two ORFs, full length L1s (FLI-L1s) and b) L1s with intact ORF2 but disrupted ORF1 (ORF2-L1s). In addition, due to their regulatory potential, the full length (>6000bp) non-intact L1s (FLnI-L1s) were also included in the database.

DAS access point

The putatively active L1s can be explored by accessing and searching the dedicated database, the L1Base. L1Base is as well available through our DAS server at http://l1das.molgen.mpg.de:8080/das. Refer to instructions on how to link the DAS server to Ensembl or consult biodas.org for appropriate software .

L1Xplorer

A web interface to the tool for identification and functional annotation of full length L1 insertions,
L1Xplorer, has been linked to the site.

Publications involving L1Base

• L1Base: from functional annotation to prediction of active LINE-1 elements
  Nucl. Acids Res. 2004 33: D498-D500; doi:10.1093/nar/gki044

• Exonization of active mouse L1s: a driver of transcriptome evolution?
  BMC Genomics 2007,8:392; doi:10.1186/1471-2164-8-392
  Exonization examples