Comparative analysis of the expressed genome of the infective juvenile entomopathogenic nematode, Heterorhabditis bacteriophora

• Published in: Molecular and biochemical parasitology 2006-02, Vol.145 (2), p.239-244
• Main Authors: Sandhu, Sukhinder K., Jagdale, Ganpati B., Hogenhout, Saskia A., Grewal, Parwinder S.
• Format: Article
• Language: English
• Subjects: 3-Phosphoinositide-Dependent Protein Kinases; Aging - genetics; Animals; Caenorhabditis elegans - genetics; cDNA libraries; Dauer juveniles; DNA, Complementary; DNA, Helminth - chemistry; DNA, Helminth - genetics; Entomopathogenic nematodes; ESTs; Expressed Sequence Tags; gene annotation; genes; genome; Genome, Helminth; genomics; GPS11 strain; Heat-Shock Proteins - genetics; Heterorhabditis bacteriophora; Membrane Proteins - genetics; Molecular Sequence Data; Nematoda; nematode larvae; nucleotide sequences; Peptide Hydrolases - genetics; Protein Kinases - genetics; Protein-Serine-Threonine Kinases - genetics; Proto-Oncogene Proteins c-akt - genetics; Receptors, G-Protein-Coupled - genetics; RGS Proteins - genetics; Rhabditida - genetics; Ribonuclease III - genetics; Sequence Analysis, DNA; sequence homology; Sequence Homology, Nucleic Acid; Superoxide Dismutase - genetics; Transforming Growth Factor beta - genetics; Transposases - genetics
• ISSN: 0166-6851; 1872-9428
• DOI: 10.1016/j.molbiopara.2006.01.002

We report the first cDNA-sequencing project of the entomopathogenic nematode, Heterorhabditis bacteriophora. A total of 1246 expressed sequence tags (ESTs) were generated by random sequencing of clones from a cDNA library of the infective juvenile stage. The ESTs were annotated resulting in 1072 useful ESTs that were categorized into functional categories according to Kyoto Encyclopedia of Genes and Genomes. Approximately 459 of 1072 ESTs (43%) had significant similarities to annotated sequences in GenBank. Of these, 417 had significant similarities to the free-living nematode Caenorhanditis elegans proteins. Most ESTs (18%) belonged to the genetic information processing category followed by metabolism (15% ESTs) and environmental information processing (15%) pathways. Several interesting ESTs were found that may have roles in the infectivity and survival of infective juveniles. These included proteases, dauer pathway genes ( akt-1, pdk-1 & daf-7) and aging and stress resistance genes such as superoxide dismutase ( sod-4), heat shock genes ( hsp-4 & hsp-6), and eat genes, and signaling proteins like G-protein coupled receptors, regulators of G-protein signaling ( rgs), and serine/threonine kinases. Other interesting ESTs include systemic RNAi defective protein ( sid-1), ribonuclease III family members ( rnh-2 & rnc) and transposase gene (Tc3A). About 67% of the ESTs did not find matches in any of the searched databases suggesting potentially novel genes in this enomopathogenic nematode.