Pre-mRNA splicing in higher plants

Most plant mRNAs are synthesized as precursors containing one or more inter vening sequences (introns) that are removed during the process of splicing. The basic mechanism of spliceosome assembly and intron excision is similar in all eukaryotes, However, the recognition of introns in plants has some unique features, which distinguishes it from the reactions in vertebrates a nd yeast, Recent progress has occurred in characterizing the splicing signa ls in plant pre-mRNAs, in identifying the mutants affected in splicing and in discovering new examples of alternatively spliced mRNAs, In combination with information provided by the Arabidopsis genome-sequencing project, the se studies are contributing to a better understanding of the splicing proce ss and its role in the regulation of gene expression in plants.