THE ARABIDOPSIS-THALIANA CDNA SEQUENCING PROJECTS

Nearly 30 000 Arabidopsis thaliana EST (Expressed Sequence Tags) have been produced by a French and an American consortium. Despite redundan cy these sequences tag about half the expected Arabidopsis genes. Appr oximately 40% of the non-redundant EST can be assigned a putative func tion by simple homology search. This programme allowed the identificat ion of a large number of genes which would have been very difficult to isolate by other classical techniques. It considerably stimulated man y areas of plant biology by the rapid discovery a large number of gene s, by revealing multigene families and by allowing the analysis of dif ferential expression of the different members. Finally this programme facilitated construction of physical maps of the chromosomes and opene d the way for complete sequencing of the Arabidopsis genome and compar ative mapping of the major plant crops. (C) 1997 Federation of Europea n Biochemical Societies.