LEUNIG, a putative transcriptional corepressor that regulates AGAMOUS expression during flower development.
Regulation of homeotic gene expression is critical for proper developmental patterns in both animals and plants. LEUNIG is a key regulator of the Arabidopsis floral homeotic gene AGAMOUS. Mutations in LEUNIG cause ectopic AGAMOUS mRNA expression in the outer two whorls of a flower, leading to homeotic transformations of floral organ identity as well as loss of floral organs. We isolated the LEUNIG gene by using a map-based approach and showed that LEUNIG encodes a glutamine-rich protein with seven WD repeats and is similar in motif structure to a class of functionally related transcriptional corepressors including Tup1 from yeast and Groucho from Drosophila. The nuclear localization of LEUNIG-GFP is consistent with a role of LEUNIG as a transcriptional regulator. The detection of LEUNIG mRNA in all floral whorls at the time of their inception suggests that the restricted activity of LEUNIG in the outer two floral whorls must depend on interactions with other spatially restricted factors or on posttranslational regulation. Our finding suggests that both animals and plants use similar repressor proteins to regulate critical developmental processes.
Conner
J
J
Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA.
Liu
Z
Z
D026342:AGAMOUS Protein, Arabidopsis; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins; D001483:Base Sequence; D002467:Cell Nucleus / Q000378:metabolism; D003001:Cloning, Molecular; D018744:DNA, Plant; D004268:DNA-Binding Proteins / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000235:genetics; D012091:Repetitive Sequences, Nucleic Acid; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D026342:AGAMOUS Protein, Arabidopsis; D029681:Arabidopsis Proteins; D018744:DNA, Plant; D004268:DNA-Binding Proteins; C417768:LUG protein, Arabidopsis; D008164:Luminescent Proteins; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; D049452:Green Fluorescent Proteins