Regulation of leaf initiation by the terminal ear 1 gene of maize

Abstract

Higher plants elaborate much of their architecture post-embryonically through development initiated at the tips of shoots¹,². During vegetative growth, leaf primordia arise at predictable sites to give characteristic leaf arrangements, or phyllotaxies³,⁴. How these sites are determined is a long-standing question⁵,⁶ that bears on the nature of pattern-formation mechanisms in plants. Fate-mapping studies in several species indicate that each leaf primordium becomes organized from a group of 100–200 cells on the flank of the shoot apex⁷. Although molecular studies indicate that the regulated expression of specific homeobox genes plays some part in this determination process^8,9,10,11, mechanisms that regulate the timing and position of leaf initiation are less well understood. Here we describe a gene from maize, terminal ear 1. Patterns of expression of this gene in the shoot and phenotypes of mutants indicate a role for terminal ear 1 in regulating leaf initiation. The te1 gene product contains conserved RNA-binding motifs, indicating that it may function through an RNA-binding activity.