Isolation of potato genes involved in response to water stress by RNA fingerprinting

We studied by cDNA-AFLP the differential expression of potato cells upon PEG-mediated osmotic stress of different intensity (5-20% PEG) and duration (15min, 1h, 24h). 17 cDNA clones were isolated and confirmed their differential expression upon stress by semiquantitative RT-PCR and Northern analysis. After sequencing, 6 clones showed high homology with genes already known to be involved in cellular response to stress (PAL, Peroxidase, ?8 desaturase, Glycin rich protein, RER protein, 1? Elongation factor). Sequence analysis of the remaining 10 cDNA clones showed that the genes have no already assigned functions and show no homology with plant gene sequences present in data bases, 5 clones are homologous to anonymous EST sequences.