Isolation and characterization of an AP2/ERF-RAV transcription factor BnaRAV-1-HY15 in Brassica napus L. HuYou15

Abstract

Transcriptional regulation is thought to be important for stress tolerance and response of transcription factors. RAV subfamily transcription factor contains an AP2- and B3-DNA binding domain, which belongs to the AP2/ERF family. It encodes transcriptional regulators with a variety of functions involved in the developmental and physiological processes in plants. Here, a RAV-like gene, BnaRAV-1-HY15, was isolated from Brassica napus L. cv HuYou15. Sequence homology analysis revealed that the BnaRAV-1-HY15 factor belongs to the RAV subfamily of the AP2/ERF family, and it shares high identity with the AtRAV2 of Arabidopsis. Sequence and three-dimensional structural analyses revealed that BnaRAV-1-HY15 contains two distinct DNA-binding domains, one AP2 domain together with one B3 domain. The AP2 domain composed of 54 amino acids and present in N-terminal region. In addition to AP2 domain, 117 amino acids show significant sequence similarity to the B3 domain present in C-terminal region. Semi-quantitative RT-PCR analysis indicated that the BnaRAV-1-HY15 gene is induced by cold, NaCl and PEG treatments. Under ABA stress, the expression of BnaRAV-1-HY15 gene was not detected. The gene expression was also not traceable from the tissues of pod, bud, petal, leaf, stem and root of normally grown B. napus L. HuYou15 plant at the period of flowering and seed development.

Genome-Wide Analysis of the RAV Family in Soybean and Functional Identification of GmRAV-03 Involvement in Salt and Drought Stresses and Exogenous ABA Treatment

“…Two Arabidopsis RAV genes ( AtRAV1L and AtRAV2 ) are transcriptionally down-regulated by drought and salt stress (Fu et al, 2014). However, Brassica napus BnaRAV-1-HY15 expression is actually induced by NaCl and PEG treatments, even though it shares high identity with the AtRAV2 of Arabidopsis (Zhuang et al, 2011). These studies emphasize that the functions of RAV genes in different species appear to be divergent.…”

Genome-wide transcriptomic analysis of cotton under drought stress reveal significant down-regulation of genes and pathways involved in fibre elongation and up-regulation of defense responsive genes

“…Recently, it has been shown that the expression of GhERF2, GhERF3 and GhERF6 increased rapidly under drought, cold and salt stresses and also in the presence of ABA and ethylene in cotton (Jin et al 2010). In Brassica napus, BnaRAV-1-HY15 was induced by ABA (Zhuang et al 2011). Wheat transgenic plants overexpressing cotton GhDREB gene that has high homology with AtRAP2.1 were shown to provide enhanced tolerance to drought, salt and freezing stresses (Gao et al 2009).…”

Functions and Application of the AP2/ERF Transcription Factor Family in Crop ImprovementF

“…RAV subfamily, related to ABI3/VP1 transcription factors, might be also involved in stress responses. B. napus RAV‐1‐HY15 is induced by cold, NaCl, and PEG treatments (Zhuang et al 2011). Overexpression of the CARAV1 gene in transgenic Arabidopsis plants induced some PR genes and enhanced resistance against infection by Pseudomonas syringae and osmotic stresses by high salinity and dehydration (Sohn et al 2006).…”