Generation of expressed sequence tags (ESTs) from banana fruit tissue

In the present investigation, a range of ESTs associated with developmental events during fruit ripening in Musa acuminata were generated. Out of the 26 recombinants obtained from normalized cDNA library, 17 inserts were sequenced. Sequence data were compared against the non-redundant combined databases using the program BLAST and functions were assigned to the ETS sequences generated. The generated sequences pertained to both housekeeping genes as well as genes involved in ripening metabolic pathways. Three sequences coding for ACC synthase, pectate lyase and polygalactouronase which are all known to be directly involved in fruit ripening were obtained. Scores of the ESTs generated were in the range of 42 to 519. From the analysis, it was found that ten ESTs out of 17 had significant homology. These ten ESTs can be used for further studies as a tool to isolate a particular gene from genomic DNA of any organism. ESTs generated in the present investigation will also help in identifying genes involved in ripening. The genes thus identified can be utilized in genetic engineering studies to enhance shelf life of fruits.