Authors

S Bachmaier¹; M K Gould¹; R Omelianczyk¹; A E Aristodemou¹; D N Tagoe³; A E Brennand¹; E Polatoglou¹; J Van Den Abbeele²; H P de Koning³; M Boshart¹;  ¹ Biocenter, Section Genetics, Ludwig-Maximilians-Universität München, Martinsried, Germany;  ² Department of Animal Health, Unit of Veterinary Protozoology, Institute of Tropical Medicine Antwerp (ITM), Antwerp, Belgium;  ³ Institute of Infection, Immunity and Inflammation, University of Glasgow

Discussion

By a recent whole genome RNAi library screen selecting for cells resistant to elevated cAMP levels, we identified several putative cAMP response proteins (CARPs) in T. brucei. The collection of CARPs verified by independent RNAi mediated knock down encompasses ten proteins that according to epistasis and interaction analyses represent components of a novel cAMP signaling network rather than a linear signaling pathway. CARP1, a protein unique to kinetoplastids, binds cAMP via three cAMP-binding like domains. Six of the verified CARPs are unique to kinetoplastids or trypanosomes. Phenotypic analysis of CARP knock down cell lines confirmed the previously described roles of cAMP signaling in normal growth and cell division in bloodstream forms. Furthermore, in procyclic forms one of the CARPs is directly involved in control of social motility, as evidenced by knockdown and knockout analyses.