Transformation schistosomes

For transformation experiments in general, biochemical or physical methods such as microinjection, electroporation or lipofection are available. These methods have been successfully applied for a variety of organisms including protozoan parasites (Clayton, 1999 De Koning-Ward et al., 2000) and were consequently tested for their ability to generate transiently transformed schistosomes by different laboratories. 

Wippersteg, V., Kapp, K., Kunz, W., Jackstadt, P., Zahner, H. and Grevelding, C.G. (2002b) HSP 70-controlled GFP expression in transiently transformed schistosomes. Molecular and Biochemical Parasitology 120, 141-150. 

Wippersteg V, Ribeiro F, Liedtke S et al (2003) The uptake of Texas Red-BSA in the excretory system of schistosomes and its colocalisation with ER60 promoter-induced GFP in transiently transformed adult males. Int J Parasitol 33 1139-1143... 

When we started to elaborate the particle bombardment technique for S. mansoni, two questions were asked. First, is it generally possible to use the biolistic approach to genetically modify schistosomes Second, if yes, does the method allow the generation of reliable and reproducible results To approach these questions, we first designed test vectors for transformation experiments. These vectors... 

Due to the auto-fluorescence of mature females, other reporter genes should be envisaged for transformation experiments in this gender such as luciferase whose applicability for schistosomes had already been demonstrated... 

RNAi in larval schistosomes was only observed if dsRNA was administered at, or shortly after, the initiation of miracidial transformation. As the time between transformation initiation and the addition of dsRNA increased, the effectiveness of the treatment decreased by 24 h, dsRNA treatment was completely ineffective at reducing target transcript levels (Boyle et al., 2003). As noted earlier, both miracidial transformation and cercarial transformation involve complex outer tegumental membrane reorganizations it may be that the... 

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