Powerful effect of an atypical bifactorial endosperm box from wheat HMWG-Dx5 promoter in maize endosperm.
The proximal region of the high-molecular-weight glutenin promoter of the Dx5 gene (PrHMWG-Dx5) carries an atypical bifactorial endosperm box containing two cis-acting elements, namely a G-box like motif followed by a prolamin-box motif (Pb1). Transient expression assays in maize endosperm indicate that a promoter fragment containing at least the G-box like element is necessary and sufficient for maximal expression of the HMWG-Dx5 promoter. In transformed maize, we have shown that a 89 bp sequence bearing the bifactorial endosperm box behaves like a functional cis-acting unit. Its repetition in tandem confers a strong specific additive effect specifically in endosperm tissue. In contrast, the fusion of the activation sequences 1 (as-1) and 2 (as-2) of the cauliflower mosaic virus (CaMV) 35S promoter with HMWG-Dx5 derived promoter sequences deregulates its activity in transformed maize. By gel mobility shift assays we have demonstrated that the G-box like motif may alternatively bind two protein groups which have the same DNA-binding affinities as the transcription factors of either the Opaque2 (O2) family and/or the ASF-1 family.
Norre
Frédéric
F
MERISTEM Therapeutics, Clermont-Ferrand, France. fnorre@meristem-therapeutics.com
Peyrot
Corinne
C
Garcia
Christian
C
Rancé
Iann
I
Drevet
Joel
J
Theisen
Manfred
M
Gruber
Véronique
V
D001483:Base Sequence; D001665:Binding Sites; D001667:Binding, Competitive; D024202:Electrophoretic Mobility Shift Assay; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000235:genetics; D005966:Glucuronidase / Q000235:genetics / Q000378:metabolism; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism; D009841:Oligonucleotides / Q000378:metabolism; D030821:Plants, Genetically Modified; D010957:Plasmids / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012639:Seeds / Q000235:genetics / Q000378:metabolism; D014908:Triticum / Q000235:genetics*; D003313:Zea mays / Q000235:genetics*
D009687:Nuclear Proteins; D009841:Oligonucleotides; D011993:Recombinant Fusion Proteins; D008156:Luciferases; D005966:Glucuronidase