A maize zinc-finger protein binds the prolamin box in zein gene promoters and interacts with the basic leucine zipper transcriptional activator Opaque2

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 94; no. 14; pp. 7685 - 7690
• Main Authors: Vicente-Carbajosa, J. (University of California at San Diego, La Jolla, CA.), Moose, S.P, Parsons, R.L, Schmidt, R.J
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences of the United States of America 08.07.1997; National Acad Sciences; National Academy of Sciences; The National Academy of Sciences of the USA
• Subjects: ADN; Amino Acid Sequence; ARN MENSAJERO; ARN MESSAGER; Basic leucine zipper transcription factors; BINDING; BINDING PROTEINS; BINDING SITES; Biological Sciences; Biology; Cereals; CLONACION; CLONAGE; CLONING; COMPLEMENTARY DNA; Corn; DNA; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; Endosperm; FACTEUR DE TRANSCRIPTION; FACTORES DE TRANSCRIPCION; GENBANK/U82230; Gene expression; Genes; Leucine Zippers; MESSENGER RNA; MOLECULAR SEQUENCE DATA; NUCLEOTIDE SEQUENCE; Plant Proteins - genetics; Plant Proteins - metabolism; PROLAMINAS; PROLAMINE; PROLAMINES; Promoter Regions, Genetic - genetics; PROTEINAS AGLUTINANTES; PROTEINE DE LIAISON; Proteins; RNA; SECUENCIA NUCLEOTIDICA; Seeds; Sequence Alignment; SEQUENCE NUCLEOTIDIQUE; TRANSCRIPTION FACTORS; Transcription Factors - genetics; Transcription Factors - metabolism; ZEA MAYS; Zea mays - genetics; Zinc Fingers
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.94.14.7685

The prolamin box (P-box) is a highly conserved 7-bp sequence element (5'-TGTAAAG-3') found in the promoters of many cereal seed storage protein genes. Nuclear factors from maize endosperm specifically interact with the P-box present in maize prolamin genes (zeins). The presence of the P-box in all zein gene promoters suggests that interactions between endosperm DNA binding proteins and the P-box may play an important role in the coordinate activation of zein gene expression during endosperm development. We have cloned an endosperm-specific maize cDNA, named prolamin-box binding factor (PBF), that encodes a member of the recently described Dof class of plant Cys2-Cys2 zinc-finger DNA binding proteins. When tested in gel shift assays, PBF exhibits the same sequence-specific binding to the P-box as factors present in maize endosperm nuclei. Additionally, PBF interacts in vitro with the basic leucine zipper protein Opaque2, a known transcriptional activator of zein gene expression whose target site lies 20 bp downstream of the P-box in the 22-kDa zein gene promoter. The isolation of the PBF gene provides an essential tool to further investigate the functional role of the highly conserved P-box in regulating cereal storage protein gene expression