Characterization of a pollen-specific and desiccation-associated AP2/ERF type transcription factor gene from castor bean (Ricinus communis L.)

Submitted: 2 July 2012
Accepted: 18 April 2013
Published: 10 September 2013
Abstract Views: 3315
PDF: 630
HTML: 94
Publisher's note
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.

Authors

DREB transcription factors (TF) belong to the superfamily of AP2/ERF and their involvement in protein-protein interactions and DNA binding has been proposed. AP2/ERF proteins have important functions in the transcriptional regulation of a variety of biological processes related to growth and development, as well as various responses to environmental stimuli, regulating expression of plant biotic and abiotic stress-responsive genes. In this study an AP2/ERF TF gene (named RcDREB1) was isolated from castor bean (Ricinus communis L.) and its expression was analyzed in developing seeds, leaves, ovules, stems and petals of plants cultivated under field conditions. Transcripts were only observed in pollen grains, peaking during anthesis. The RcDREB1 deduced amino acid sequence was compared to other AP2/ERF TF proteins and presented 38-78% identity. Phylogenetic analysis classified it as a member of the CBF/DREB subfamily, rooting with the subgroup A-5. The RcDREB1 promoter was fused to the gus reporter gene and used to transform tobacco. Transgenic plants were exposed to various abiotic stress treatments (low and high tempera- tures, drought, salinity and exogenous ABA) and no detectable GUS expression was observed, suggesting that the RcDREB1 promoter is not active under tested conditions. In silico analyses revealed the presence of three copies of the regulatory late pollen-specific element (AGAAA) in the RcDREB1 5 ́-region. Interestingly, GUS expression was only observed in pollen grains, starting when the flower opened and initiating the senescence process; at this point, desiccated mature pollen grains are released from anthers. In addition, dehydrated developing pollen grains also expressed the gus gene. This is the first study on a DREB gene presenting pollen-specific expression.

Dimensions

Altmetric

PlumX Metrics

Downloads

Download data is not yet available.

Citations

Supporting Agencies

CAPES, CNPq

How to Cite

Cipriano, T. de M., Morais, A. T., & Aragão F. J. L. (2013). Characterization of a pollen-specific and desiccation-associated AP2/ERF type transcription factor gene from castor bean (Ricinus communis L.). International Journal of Plant Biology, 4(1), e1. https://doi.org/10.4081/pb.2013.e1