PMID- 19319915 OWN - NLM STAT- MEDLINE DCOM- 20090608 LR - 20101118 IS - 1521-1878 (Electronic) IS - 0265-9247 (Linking) VI - 31 IP - 5 DP - 2009 May TI - How did parasitic worms evolve? PG - 496-9 LID - 10.1002/bies.200900010 [doi] AB - Nematodes are important parasites of humans and other animals. Nematode parasitism is thought to have evolved by free-living, facultatively developing, arrested larvae becoming associated with animals, ultimately becoming parasites. The formation of free-living arrested larvae of the nematode Caenorhabditis elegans is controlled by the environment, and involves dafachronic acid (DA) and transforming growth factor (TGF)-beta signalling. Recent data have shown that DA acid signalling plays a conserved role in controlling larval development in both free-living and parasitic species. In contrast, TGF-beta signalling does not seem to be conserved; this difference perhaps points to how nematode parasitism did evolve. FAU - Viney, Mark E AU - Viney ME AD - School of Biological Sciences, University of Bristol, Bristol, UK. LA - eng PT - Journal Article PL - United States TA - Bioessays JT - BioEssays : news and reviews in molecular, cellular and developmental biology JID - 8510851 RN - 0 (Cholestenes) RN - 0 (Transforming Growth Factor beta) RN - 0 (dafachronic acid) SB - IM MH - Animals MH - *Biological Evolution MH - Caenorhabditis elegans/growth & development/metabolism/physiology MH - Cholestenes/metabolism MH - Environment MH - Host-Parasite Interactions/*physiology MH - Humans MH - Nematoda/growth & development/metabolism/*physiology MH - Transforming Growth Factor beta/metabolism EDAT- 2009/03/26 09:00 MHDA- 2009/06/09 09:00 CRDT- 2009/03/26 09:00 PHST- 2009/03/26 09:00 [entrez] PHST- 2009/03/26 09:00 [pubmed] PHST- 2009/06/09 09:00 [medline] AID - 10.1002/bies.200900010 [doi] PST - ppublish SO - Bioessays. 2009 May;31(5):496-9. doi: 10.1002/bies.200900010.