The Arabidopsis SERRATE gene encodes a zinc-finger protein required for normal shoot development

Organogenesis in plants depends upon the proper regulation of many genes, b ut how such necessary changes in gene expression are coordinated is largely unknown. The serrate (se) mutant of Arabidopsis displays defects in the in itiation and elaboration of cotyledons and post-embryonic lateral organs. C loning the SE gene revealed that it encodes a protein with a single, C2H2-t ype, zinc finger related to genes in other eukaryotes, Consistent with a ro le in organogenesis, the SE gene is transcribed in shoot meristems and in e merging organ primordia throughout development. Expression of the SE cDNA u nder the control of a heterologous promoter caused both accelerated and arr ested plant growth, and these phenotypes were due to overexpression and cc- suppression of the SE gene, respectively. Our analysis of the se mutant and the SE gene suggests a role for the SE gene product in regulating changes in gene expression via chromatin modification. Consistent with this propose d function, a synergistic double mutant phenotype was seen for plants mutan t at both the SE locus and the locus encoding the largest subunit of chroma tin assembly factor I.