Cereal endosperm tissues account for most of the world's calorific intake, yet the regulation of monocot seed development remains poorly understood. The maize endosperm originates with a series of free-nuclear divisions, followed by cellularisation and subsequent formation of a range of functional cellular domains. We describe the isolation and characterisation of a mutation that induces aberrant globular embryo and endosperm morphology, globby1-1 (glo1-1). Our data indicate that glo1-1 plays...