Title: Transcript Analysis of Sedentary Parastic Female Reniform Nematodes (Rotylenchulus reniformis) Identifies Candidate Parasitism Genes and Targets for RNA-Interference Authors
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: November 20, 2009
Publication Date: January 9, 2010
Citation: Wubben, M., Callahan, F.E., Scheffler, B.E. 2010. Transcript analysis of sedentary parastic female reniform nematodes (Rotylenchulus reniformis) identifies candidate parasitism genes and targets for RNA-interference. Proceedings Plant and Animal Genome Conference. CD-ROM. Technical Abstract: The reniform nematode (RN) (Rotylenchulus reniformis) is a semi-endoparasitic nematode with a host range that spans 30 plant families; however, RN infection is particularly detrimental to Upland cotton (Gossypium hirsutum). We present here an initial survey of cDNA sequences isolated from the RN female parasitic life-stage. 2,784 clones were bi-directionally sequenced, of which 1,995 remained after screening for low quality, vector, ribosomal, and mitochondrial sequences. These 1,995 expressed sequence tags (ESTs) were condensed to 136 contigs and 517 singletons for a total of 653 RN unigenes. 27% and 38% of unigenes showed significant (E = 1e-03) alignments following BLASTn and BLASTx analyses, respectively. At least one Gene Ontogeny (GO) identity was assigned to 239 unigenes, while InterProScan detected positive hits for 339 unigenes. 31 unigenes were predicted to encode serine-type proteinase inhibitor (PI) proteins. Six of these 31 PI proteins failed to show significant homology to PIs from Caenorhabditis elegans, but tended to show homology to anti-blood coagulant proteins from ticks and mosquitoes and/or to venom proteins from snakes or poison arrow tree frogs. Putative ‘parasitism genes’ were also identified and included a cellulase gene and a homolog of the Heterodera glycines esophageal gland cDNA G22C12; in addition, 78 unigenes of unknown function were predicted to be secreted outside of the cell by SignalP 3.0. Furthermore, RN orthologues of C. elegans genes having lethal RNAi phenotypes were identified. This work represents the first analysis of the RN transcriptome and that of a semi-endoparasitic nematode in general.