Analysis of the translationally controlled tumour protein in the nematodes Ostertagia ostertagi and Caenorhabditis elegans suggests a pivotal role in egg production.

The translationally controlled tumour protein (TCTP) is a conserved protein which has been described for a wide range of eukaryotic organisms including protozoa, yeasts, plants, nematodes and mammals. Several parasitic organisms have been shown to actively secrete TCTP during host infection as part of their immuno-evasive strategy. In this study, we have studied TCTP in Ostertagia ostertagi, a parasitic nematode of cattle, and in the free-living nematode Caenorhabditis elegans. An analysis of the transcription and expression patterns showed that TCTP was present in the eggs of both species. This localisation is consistent for some other Strongylida such as Teladorsagia circumcincta, Cooperia oncophora and Haemonchus contortus. TCTP was also detected at low levels in excretory-secretory material from adult O. ostertagi worms. The role of TCTP in nematode biology was also investigated by RNA interference in C. elegans. Knock-down of C. elegans tctp (tct-1) transcription reduced the numbers of eggs laid by the hermaphrodite in the F(0) and F(1) generations by 90% and 72%, respectively, indicating a pivotal role of TCTP in reproduction.