There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
A fundamental problem in biology is to understand how fertilization initiates reproductive
development. Higher plant reproduction is unique because two fertilization events
are required for sexual reproduction. First, a sperm must fuse with the egg to form
an embryo. A second sperm must then fuse with the adjacent central cell nucleus that
replicates to form an endosperm, which is the support tissue required for embryo and/or
seedling development. Here, we report cloning of the Arabidopsis FERTILIZATION-INDEPENDENT
ENDOSPERM (FIE) gene. The FIE protein is a homolog of the WD motif-containing Polycomb
proteins from Drosophila and mammals. These proteins function as repressors of homeotic
genes. A female gametophyte with a loss-of-function allele of fie undergoes replication
of the central cell nucleus and initiates endosperm development without fertilization.
These results suggest that the FIE Polycomb protein functions to suppress a critical
aspect of early plant reproduction, namely, endosperm development, until fertilization
occurs.