Plant & Animal Genome IX Conference Plant & Animal Genome IX Conference
Poster: Sequencing & EST
P01_25.html
Red chicory (Cichorium intybus L.) is characterized by a sporophytic incompatibility mechanism. This research deals with the optimization of a DD-cDNA-AFLP for the visualization of gene expression during flowering in C. intybus x C. endivia hybrids segregating for the incompatibility reaction. Both Eco-RI/Mse-I (regular DD) and Mse-I/Oligo-dT (ordered DD) primer combinations were adopted for achieving the mRNA fingerprinting of flower buds at different developmental stages of self-compatible and self-incompatible plants. The approach enabled to select parent-specific transcripts and to detect transcriptional changes potentially related to the incompatibility behavior. A subset of 20 polymorphic TDFs were sequenced and this information used for gene data banks queries. Sequence alignments of the ESTs mostly revealed genes of unknown function. However, four sequences varying between 105 and 150 bp in length showed significant homologies in BLAST databases. In particular, clones related to a putative pollen-specific ascorbate-oxidase protein precursor and to a pectinesterase-like protein were found. Another clone proved to be involved in nucleo-plasmatic transport pathways being similar to chromosome region maintenance (CRM1) and to putative exportin (XPO1) proteins. One of the ESTs was highly homologue to DnaJ multi-gene family which encodes chaperones responsible for proper protein folding and targeting, and which acts in mitochondrial as well as in nuclear import. On the whole, cDNA-AFLP retrieved useful information on gene expression level and on its changes, even though untranslated sequences at the 3' template ends can be yielded. Research is in progress and a number of polymorphic TDFs will be processed to develop additional ESTs.