Abstract
The synthesis of EPB, a cysteine proteinase responsible for the degradation of seed endosperm storage proteins in barley (Hordeum vulgare), is induced by gibberellins (GA) and repressed by abscisic acid (ABA). The EPB gene family consists of two very similar members, EPB-1 and EPB-2, with the former being more highly induced by GA. We have functionally characterized the cis-acting elements in the EPB-1 promoter and determined that a gibberellin response element (GARE), a pyrimidine box and an upstream element are necessary for GA induction. By comparison with the promoters of alpha-amylase genes, which are also induced by GA, we suggest that GARE is coupled with the upstream element and the pyrimidine box to form a GA response complex. In addition, we have shown that the 3'-untranslated/untranscribed region of the EPB-1 gene is required for a low background expression in the absence of GA. Constitutive expression of a transcription factor, GAMyb, in the absence of GA leads to the transactivation of EPB-1 expression in a dosage dependent manner with the highest level comparable to that in fully GA-induced tissue. Co-expression of a truncated version of GAMyb containing only the DNA binding domain blocks the GA-induction of EPB-1, further supporting the role of GAMyb in the regulation of gene expression. Although ABA is very effective in blocking the GA induction of EPB-1, it has no effect on the GAMyb-mediated expression of EPB-1. We suggest that ABA acts upstream of the formation of functional GAMyb which co-ordinates the hormonal regulation of a diverse group of genes in cereal aleurone layers, including those encoding EPB and alpha-amylases.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 6
Claim · model-written summary
The EPB-1 3-prime region was required for low background expression without GA.
- Taxon
- barley
.jpg?width=60)
Hordeum vulgaree1 - Gene
- EPB-1e0
- Outcome
- low background expressione0
- Qualifier
- 3'-untranslated/untranscribed regione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“the 3'-untranslated/untranscribed region of the EPB-1 gene is required for a low background expression in the absence of GA”
e1“in barley”
Claim · model-written summary
Constitutive GAMyb expression transactivated EPB-1 without GA in a dose-dependent manner.
- Taxon
- barleyHordeum vulgaree1
- Treatment
- Constitutive expression of a transcription factor, GAMybe0
- Gene
- GAMybe0
- Outcome
- EPB-1 expressione0
- Direction
- transactivatione0
- Qualifier
- in a dosage dependent mannere0
- Comparator
- fully GA-induced tissuee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Constitutive expression of a transcription factor, GAMyb, in the absence of GA leads to the transactivation of EPB-1 expression in a dosage dependent manner with the highest level comparable to that in fully GA-induced tissue”
e1“in barley”
Claim · model-written summary
A truncated GAMyb DNA-binding domain blocked GA induction of EPB-1.
- Taxon
- barleyHordeum vulgaree1
- Treatment
- Co-expression of a truncated version of GAMyb containing only the DNA binding domaine0
- Gene
- GAMybe0
- Outcome
- GA-induction of EPB-1e0
- Direction
- blockse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Co-expression of a truncated version of GAMyb containing only the DNA binding domain blocks the GA-induction of EPB-1”
e1“in barley”
Claim · model-written summary
ABA blocked GA induction of EPB-1.
- Taxon
- barleyHordeum vulgaree1
- Treatment
- ABAe0
- Gene
- EPB-1e0
- Outcome
- GA induction of EPB-1e0
- Direction
- blockinge0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“ABA is very effective in blocking the GA induction of EPB-1”
e1“in barley”
Claim · model-written summary
ABA had no effect on GAMyb-mediated EPB-1 expression.
- Taxon
- barleyHordeum vulgaree1
- Treatment
- ABAe0
- Gene
- GAMybe0
- Outcome
- GAMyb-mediated expression of EPB-1e0
- Direction
- no effecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Although ABA is very effective in blocking the GA induction of EPB-1, it has no effect on the GAMyb-mediated expression of EPB-1”
e1“barley (Hordeum vulgare)”
Claim · model-written summary
The authors suggest ABA acts upstream of functional GAMyb formation.
- Taxon
- barleyHordeum vulgaree1
- Treatment
- ABAe0
- Gene
- GAMybe0
- Outcome
- formation of functional GAMybe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“ABA acts upstream of the formation of functional GAMyb”
e1“in barley”
The same questions in other papers
(+)-abscisic acid · molecular: expression · Hordeum vulgare (barley)Results differ
8 papers in the same direction as this paper · 6 in the opposite direction
- positive
- no effect
- positive
11 papers more in this group
See all 15 papers →overexpression · molecular: expression · Hordeum vulgare (barley)Positive and negative results
1 in the opposite direction
- negative
Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.