Identification of Differentially Expressed Genes during Lace Plant Leaf Development

Abstract

Premise of research.The lace plant is an excellent and unique model for studying developmentally regulated programmed cell death (PCD) in plants. Perforations form in highly predictable and easily accessible and distinguishable areas in lace plant leaves. However, little is known about the genes involved in regulation of this PCD or leaf development. In this study, for the first time, a general gene expression profile for lace plant leaf development was investigated.Methodology.A cDNA-amplified fragment length polymorphism involving 64 primer combinations was used for a half-genome analysis of 4666 transcripts. Two hundred and thirty differentially expressed transcript-derived fragments (TDFs) were sequenced. A partial expressed sequence tag (EST) database for window-stage (in which PCD is occurring) leaves was also established. Through a reverse transcription polymerase chain reaction, the possible role of ubiquitin in lace plant PCD was investigated.Pivotal results.Seventy-nine TDFs were successfully annotated. The isolated TDFs and ESTs encoded genes involved in processes such as photosynthesis, biosynthesis pathways, gene regulation, stress responses, defense against pathogens, and PCD, among others. Indirect evidence through ubiquitin transcript levels suggests involvement of proteasome machinery in lace plant development and PCD. This study provides a foundation for selective studies on regulation of lace plant leaf development and PCD.