THE INDETERMINATE GENE ENCODES A ZINC-FINGER PROTEIN AND REGULATES A LEAF-GENERATED SIGNAL REQUIRED FOR THE TRANSITION TO FLOWERING IN MAIZE

Flowering in plants is a consequence of the transition of the shoot ap ex from vegetative to reproductive growth in response to environmental and internal signals. The indeterminate 1 gene (id1) controls the tra nsition to flowering in maize. We show by cloning the id1 gene that it encodes a protein with zinc finger motifs, suggesting that the id1 ge ne product functions as a transcriptional regulator of the floral tran sition, id1 mRNA expression studies and analyses of transposon-induced chimeric plants indicate that id1 acts non-cell-autonomously to regul ate the production of a transmissible signal in the leaf that elicits the transformation of the shoot apex to reproductive development. Thes e results provide molecular and genetic data consistent with the flori gen hypothesis derived from classical plant physiology studies.