Members of a new family of DNA-binding proteins bind to a conserved cis-element in the promoters of alpha-Amy2 genes.
The promoters of wheat, barley and wild oat alpha-Amy2 genes contain a number of conserved cis-acting elements that bind nuclear protein, we report here the isolation of two cDNAs encoding proteins (ABF1 and ABF2) that bind specifically to one of these elements, Box 2 (ATTGACTTGACCGTCATCGG). The two proteins are unrelated to each other except for a conserved region of 56-58 amino acids that consists of 25 highly conserved amino acids followed by a putative zinc finger motif, C-X4-5-C-X22-23-H-X1-H. ABF1 contains two such conserved regions, whereas ABF2 possesses only one but also contains a potential leucine zipper motif, suggesting that it could form homo- or heterodimers. ABF1 and ABF2 expressed in Escherichia coli bound specifically to Box 2 probes in gel retardation experiments; this binding was abolished by the transition-metal-chelating agent, 1,10-o-phenanthroline and by EDTA. We propose that ABF1 and ABF2 are representatives of two classes of a new family of plant sequence-specific DNA-binding proteins.
Rushton
P J
PJ
IACR-Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol, Long Ashton, UK.
Macdonald
H
H
Huttly
A K
AK
Lazarus
C M
CM
Hooley
R
R
D000595:Amino Acid Sequence; D018554:Avena / Q000201:enzymology / Q000235:genetics*; D001483:Base Sequence; D015152:Blotting, Northern; D017124:Conserved Sequence; D018744:DNA, Plant / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D015723:Gene Library; D008969:Molecular Sequence Data; D005810:Multigene Family; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011994:Recombinant Proteins / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D012641:Selection, Genetic; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D000516:alpha-Amylases / Q000235:genetics*
C061886:ABF1 protein, S cerevisiae; C072843:ABF2 protein, S cerevisiae; D018744:DNA, Plant; D004268:DNA-Binding Proteins; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D000516:alpha-Amylases