Identification of novel mRNAs in immature seeds of Arabidopsis thaliana.

Although most of the major discernible morphogenetic events in plants occur after germination, the overall architectural pattern of the mature plant is established during early events of embryogenesis. So far, few genes that are expressed specifically during embryogenesis have been identified. This is due primarily to technical difficulties associated with the mass ratios of the embryo and the surrounding maternal tissue and to the lack of molecular and cellular markers to direct screening efforts. We have developed a series of molecular approaches to study the early events of embryogenesis. These include 'virtual subtraction' of a cDNA library with high specific-activity cDNA probes generated from both seed and non-seed tissue, PCR amplification of gene family members from an immature seed cDNA library using primers specific to conserved domains, differential display analysis of mRNA populations and high throughput expressed sequence tag (EST) analysis. These techniques have led to the identification and isolation of several novel seed-specific cDNAs.