POUCHKINA-STANTCHEVA, N.; TUNNACLIFFE, A.; Institute of Biotechnology, University of Cambridge, Cambridge, CB2 1QT, UK; Institute of Biotechnology, University of Cambridge, Cambridge, CB2 1QT, UK: Molecular studies of anhydrobiosis in bdelloid rotifers

Bdelloid rotifers are renowned for their ability to survive extreme desiccation. Generally, onset of anhydrobiosis in Bdelloidea is characterised by reduced metabolism, arrested development and adjustments of morphology. However, very little is known about the molecular events underlying their ability to withstand extreme desiccation and currently only a few Bdelloidea genes are characterised at the molecular level. In order to identify genes involved in rotifer anhydrobiosis two Adineta ricciae cDNA populations at two different stages were produced (control animals and animals that were dehydrated for 6 hrs). cDNA generated after 6 hrs of dehydration was then subtracted against control non-dehydrated cDNA in order to reveal genes that are differentially expressed upon desiccation. In total 78 sequences were analysed, of which 51 were found to be non-redundant. Some of the genes identified appeared to be sensors and biomarkers of stress responses and included transcriptional regulators, stress inducible genes involved in targeted protein degradation, structural ribosomal proteins, and genes implicated in cell death and general metabolism. However, the majority of sequences analysed have no significant similarity to known proteins and are likely to represent novel dehydration-inducible rotifer genes. The set of genes induced by dehydration will be confirmed by Northern analysis and quantitative PCR studies; further assessment of their importance in desiccation tolerance will be obtained after functional knockdown by RNAi.