Seed development requires coordinated expression of embryo and endosperm. a
nd has contributions from both sporophytic and male and female gametophytic
genes. Genetic and molecular analyses in recent years have started to illu
minate how products of these multiple genes interact to initiate seed devel
opment. Imprinting or differential expression of paternal and maternal gene
s seems to be involved in controlling seed development, presumably by contr
olling gene expression in developing endosperm. Epigenetic processes such a
s chromatin remodeling and DNA methylation affect imprinting of key seed-sp
ecific genes; however, the identity of many of these genes remains unknown.
The discovery of FIS genes has illuminated control of autonomous endosperm
development, a component of apomixis, which is an important developmental
and agronomic trait. FIS genes are targets of imprinting, and the genes the
y control in developing endosperm are also regulated by DNA methylation and
chromatin remodeling genes. These results define some exciting future area
s of research in seed development.