Analysis of cDNAs expressed during first cell division of petunia petal protoplast cultures using expressed sequence tags

A large-scale sequence analysis of randomly selected cDNA clones was perfor med to isolate numerous genes in petunia petal protoplast cultures, We have partially sequenced 1158 randomly selected genes of the cDNA library const ructed from 2-6 d cultured petal protoplasts. Three hundred and sixty-five different genes were identified, 25% of which showed significant similarity to existing sequences in the petunia, and an array of other organisms. In this report, 90 independent genes are analyzed in detail. A functional cate gorization of the database-matched expressed sequence tags (ESTs) showed th at defense- or stress-related genes, as well as genes involved in the prima ry metabolic pathways and in the transcriptional or translational apparatus are abundantly represented. In particular, ESTs were identified with appar ent homologies to the cyclin-dependent kinase, histone, actin-depolymerizin g factor, proteasome, and ubiquitin which are expected to be related to cel l division or to cell cycle control.