Cloning, analysis and functional annotation of expressed sequence tags from the Earthworm Eisenia fetida

Background: Eisenia fetida, commonly known as red wiggler or compost worm, belongs to the Lumbricidae family of the Annelida phylum. Little is known about its genome sequence although it has been extensively used as a test organism in terrestrial ecotoxicology. In order to understand its gene expression response to environmental contaminants, we cloned 4032 cDNAs or expressed sequence tags (ESTs) from two E. fetida libraries enriched with genes responsive to ten ordnance related compounds using suppressive subtractive hybridization-PCR. Results: A total of 3144 good quality ESTs (GenBank dbEST accession number EH669363– EH672369 and EL515444–EL515580) were obtained from the raw clone sequences after cleaning. Clustering analysis yielded 2231 unique sequences including 448 contigs (from 1361 ESTs) and 1783 singletons. Comparative genomic analysis showed that 743 or 33% of the unique sequences shared high similarity with existing genes in the GenBank nr database. Provisional functio...

• Type: Journal
• Year: 2007
• Where: BMCBI
• Authors: Mehdi Pirooznia, Ping Gong, Xin Guan, Laura S. Inouye, Kuan Yang, Edward J. Perkins, Youping Deng
• Keywords: BMCBI 2007, ESTs, Fourth Annual MCBIOS, Unique Sequences