Identification and Expression Profiling of the Auxin Response Factors in Dendrobium officinale under Abiotic Stresses

Abstract

Auxin response factor (ARF) proteins play roles in plant responses to diverse environmental stresses by binding specifically to the auxin response element in the promoters of target genes. Using our latest public Dendrobium transcriptomes, a comprehensive characterization and analysis of 14 DnARF genes were performed. Three selected DnARFs, including DnARF1, DnARF4, and DnARF6, were confirmed to be nuclear proteins according to their transient expression in epidermal cells of Nicotiana benthamiana leaves. Furthermore, the transcription activation abilities of DnARF1, DnARF4, and DnARF6 were tested in a yeast system. Our data showed that DnARF6 is a transcriptional activator in Dendrobium officinale. To uncover the basic information of DnARF gene responses to abiotic stresses, we analyzed their expression patterns under various hormones and abiotic treatments. Based on our data, several hormones and significant stress responsive DnARF genes have been identified. Since auxin and ARF genes have been identified in many plant species, our data is imperative to reveal the function of ARF mediated auxin signaling in the adaptation to the challenging Dendrobium environment.

Transcriptome analysis of the induction of somatic embryogenesis in Coffea canephora and the participation of ARF and Aux/IAA genes

“…Several studies have allowed the identification of the role of some of the 23 ARFs and 29 Aux/IAAs in the presence of auxins at different stages of plant development, using mutants of loss or gain of function in A. thaliana (Liscum & Reed, 2002). To mention a few, ARF5 is critical for the formation of the embryonary axis and the embryogenic root, and the development of the flowers, as well as part of the vascular tissue; ARF6 acts in the maturation of the flowers and, in tomato, ARF9 regulates cell division (Li et al, 2015; Li et al, 2016; Weijers & Wagner, 2016; Chen et al, 2017). Regarding Aux/IAA proteins, studies in A. thaliana have shown that mutations in the Aux/IAA7 gene produce short hypocotyl phenotypes and deformities in the leaves; mutations in the Aux/IAA12 gene cause root abnormalities (Liscum & Reed, 2002).…”

Identification and Expression Profiling of the Auxin Response Factors in Capsicum annuum L. under Abiotic Stress and Hormone Treatments

“…Phytohormones are involved in the responses of various plants to environmental stimuli and stress by altering the expression levels of many ARF genes [ 6 , 51 ]. However, evaluation of pepper’s adaptability to its environment is very limited.…”

Peer Review #2 of "Transcriptome analysis of the induction of somatic embryogenesis in Coffea canephora and the participation of ARF and Aux/IAA genes (v0.1)"

“…Several studies have allowed the identification of the role of some of the 23 ARFs and 29 Aux/IAAs in the presence of auxins at different stages of plant development, using mutants of loss or gain of function in A. thaliana (Liscum & Reed 2002). To mention a few, ARF5 is critical for the formation of the embryonary axis and the embryogenic root, and the development of the flowers, as well as part of the vascular tissue; ARF6 acts in the maturation of the flowers and, in tomato, ARF9 regulates cell division (Li et al, 2015;Weijers & Wagner 2016;Chen et al, 2017). Regarding Aux/IAA proteins, studies in A. thaliana have shown that mutations in the Aux/IAA7 gene produce short hypocotyl phenotypes and deformities in the leaves; mutations in the Aux/IAA12 gene cause root abnormalities (Liscum & Reed 2002).…”