encodes a prolamin-box-binding transcription factor that controls embryo growth in barley and wheat.

Mutations at the locus in barley have multiple effects on grain development, including an increase in embryo size and a decrease in endosperm starch content. The gene underlying was identified by genetic mapping and mutations in this gene were identified in all four barley alleles. encodes a transcription factor called Prolamin Binding Factor (PBF). Its role in controlling embryo size was confirmed using wheat TILLING mutants. To understand how controls embryo development, we studied its spatial and temporal patterns of expression in developing grains. The gene is expressed in both the endosperm and the embryos, but the timing of expression in these organs differs. expression in wild-type embryos precedes the onset of embryo enlargement in mutants, suggesting that suppresses embryo growth. We predicted the down-stream target genes of in wheat and found them to be involved in a wide range of biological processes, including organ development and starch metabolism Our work suggests that may influence embryo size and endosperm starch synthesis via separate gene control networks.