Cloning and Characterization of a Gibberellin-Induced RNase Expressed in Barley Aleurone Cells1
AUTOR(ES)
Rogers, Sally W.
FONTE
American Society of Plant Physiologists
RESUMO
We cloned a cDNA for a gibberellin-induced ribonuclease (RNase) expressed in barley (Hordeum vulgare) aleurone and the gene for a second barley RNase expressed in leaf tissue. The protein encoded by the cDNA is unique among RNases described to date in that it contains a novel 23-amino acid insert between the C2 and C3 conserved sequences. Expression of the recombinant protein in tobacco (Nicotiana tabacum) suspension-cultured protoplasts gave an active RNase of the expected size, confirming the enzymatic activity of the protein. Analyses of hormone regulation of expression of mRNA for the aleurone RNase revealed that, like the pattern for α-amylase, mRNA levels increased in the presence of gibberellic acid, and its antagonist abscisic acid prevented this effect. Quantitative studies at early times demonstrated that cycloheximide treatment of aleurone layers increased mRNA levels 4-fold, whereas a combination of gibberellin plus cycloheximide treatment was required to increase α-amylase mRNA levels to the same extent. These results are consistent with loss of repression as an initial effect of gibberellic acid on transcription of those genes, although the regulatory pathways for the two genes may differ.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=32031Documentos Relacionados
- Gibberellin-induced Fertility in the Fern Ceratopteris thalictroides (L.) Brongn. 1
- Interaction of a gibberellin-induced factor with the upstream region of an alpha-amylase gene in rice aleurone tissue.
- A Novel Gibberellin-Induced Gene from Rice and Its Potential Regulatory Role in Stem Growth1
- Repressing a Repressor: Gibberellin-Induced Rapid Reduction of the RGA Protein in Arabidopsis
- Sugar-Dependent Gibberellin-Induced Chalcone Synthase Gene Expression in Petunia Corollas.
