Phylogenetic analysis of F-bZIP transcription factors indicates conservation of the zinc deficiency response across land plants

Abstract

Basic leucine zipper (bZIP) transcription factors control important developmental and physiological processes in plants. In Arabidopsis thaliana, the three gene F-bZIP subfamily has been associated with zinc deficiency and salt stress response. Benefiting from the present abundance of plant genomic data, we performed an evolutionary and structural characterization of plant F-bZIPs. We observed divergence during seed plant evolution, into two groups and inferred different selective pressures for each. Group 1 contains AtbZIP19 and AtbZIP23 and appears more conserved, whereas Group 2, containing AtbZIP24, is more prone to gene loss and expansion events. Transcriptomic and experimental data reinforced AtbZIP19/23 as pivotal regulators of the zinc deficiency response, mostly via the activation of genes from the ZIP metal transporter family, and revealed that they are the main regulatory switch of AtZIP4. A survey of AtZIP4 orthologs promoters across different plant taxa revealed an enrichment of the Zinc Deficiency Response Element (ZDRE) to which both AtbZIP19/23 bind. Overall, our results indicate that while the AtbZIP24 function in the regulation of the salt stress response may be the result of neo-functionalization, the AtbZIP19/23 function in the regulation of the zinc deficiency response may be conserved in land plants (Embryophytes).

Transcriptome profiles of soybean leaves and roots in response to zinc deficiency

“…Arabidopsis F‐group bZIP TF bZIP19 and bZIP23 have been shown to be essential for the Zn homeostasis regulation (Assunção et al , Inaba et al ). The F‐group bZIP TFs in other plants such as wheat and barley were also found to have a similar function in Zn‐deficiency response (Castro et al , Evens et al , Nazri et al ). There are also two members of F‐group bZIP TFs in soybean genome, GmbZIP121 ( Gm11g108100 ) and GmbZIP122 ( Gm12g033000 ) (Liao et al ).…”

“…The F-group bZIP TFs in other plants such as wheat and barley were also found to have a similar function in Zn-deficiency response (Castro et al 2017, Evens et al 2017, Nazri et al 2017. There are also two members of F-group bZIP TFs in soybean genome, GmbZIP121 (Gm11g108100) and GmbZIP122 (Gm12g033000) (Liao et al 2008).…”

Arabidopsis thaliana SPF1 and SPF2 are nuclear-located ULP2-like SUMO proteases that act downstream of SIZ1 in plant development

“…Phylogenetic analysis was performed using maximum likelihood (RaxML) with 1000 bootstrap iterations, as previously described (Castro et al , 2017). The final output of the tree was produced using the SeaView v4.4.0 software (Gouy et al , 2010).…”

Nach is a novel ancestral subfamily ofthe CNC-bZIP transcription factors selected during evolution from the marine bacteria to human

“…Immediately with accumulating analyses of the elaborate bZIP-mediated transcriptional networks within distinct eukaryotes, their evolutionary process had also been investigated in animals (17, 18), fungi (19) and plants (20). For example, the bZIP superfamily in Metazoan was thought to be evolved from a single ancestral eukaryotic gene, which had undergone multiple independent expansions and three major evolution periods.…”

“…By contrast, similar transcription factors of the bZIP uperfamily existing in animals appear to have originated throughout the eukaryotic evolution process before the dawn of the Metazoa. This is supported by the fact that some of the highly conserved bZIP family proteins also emerged in the protozoa, such as choanoflagellate (Monosiga brevicollis) and protist (Capsaspora owczarzaki) (17), in addition to the presence of orthologues in the Metazoa.Immediately with accumulating analyses of the elaborate bZIP-mediated transcriptional networks within distinct eukaryotes, their evolutionary process had also been investigated in animals (17, 18), fungi (19) and plants (20). For example, the bZIP superfamily in Metazoan was thought to be evolved from a single ancestral eukaryotic gene, which had undergone multiple independent expansions and three major evolution periods.…”