Seed maturation: genetic programmes and control signals.

Seed maturation is mainly governed by a few genes best studied in maize and Arabidopsis. The isolation of the LEC1 and FUS3 genes, besides the previously known VP1/AB/3 genes, and their identification as transcriptional regulators provides the first direct hints as to their molecular mode of action. With the identification of new effector genes, the investigation of the role of hormones with new methods such as immunomodulation and the increasingly recognised role of metabolites like sugars as important modulators of seed development, we increasingly understand the complexity and structure of the regulatory network underlying seed maturation.