A reverse genetics approach identifies novel mutants in light responses and anthocyanin metabolism in petunia

Abstract

Flower color and plant architecture are important commercially valuable features for ornamental petunias (Petunia x hybrida Vilm.). Photoperception and light signaling are the major environmental factors controlling anthocyanin and chlorophyll biosynthesis and shadeavoidance responses in higher plants. The genetic regulators of these processes were investigated in petunia by in silico analyses and the sequence information was used to devise a reverse genetics approach to probe mutant populations. Petunia orthologs of photoreceptor, light-signaling components and anthocyanin metabolism genes were identified and investigated for functional conservation by phylogenetic and protein motif analyses. The expression profiles of photoreceptor gene families and of transcription factors regulating anthocyanin biosynthesis were obtained by bioinformatic tools. Two mutant populations, generated by an alkalyting agent and by gamma irradiation, were screened using a phenotype-independent, sequence-based method by high-throughput PCR-based assay. The strategy allowed the identification of novel mutant alleles for anthocyanin biosynthesis (CHALCONE SYNTHASE ) and regulation (PH4), and for light signaling (CONSTANS ) genes.

Bacillus: A Biological Tool for Crop Improvement through Bio-Molecular Changes in Adverse Environments

“…In bacteria-treated plants, APX and SOD activities are decreased, while nitrate reductase (NR; EC 1.7.1.1), CAT and POD activities are enhanced (Jha and Subramanian, 2012 , 2015 ). Bacillus pumilus associated with the roots of salt-stressed rice plants reduces the activity of caspase (Jha and Subramanian, 2014 ), which is a protease that belongs to the cysteine endopeptidase family and is involved in programmed cell death in plants (Groten et al, 2006 ). The reduction of caspase activity decreases ROS formation and programmed cell death and reprograms the action of antioxidants to accomplish plant tolerance (Jha and Subramanian, 2014 ).…”

Effect of salt stress on ion concentration, proline content, antioxidant enzyme activities and gene expression in tomato cultivars

“…Oxidative stress defenses occur through enzymatic antioxidant mechanism including catalase (CAT), superoxide dismutase (SOD), peroxidase (POX) and enzymes of the ascorbate-glutathione cycle as ascorbate peroxydase (APX), monodehydroascorbate dehydrogenase (MDHAR), dehydroascorbate reductase (DHAR) (Foyer and Noctor 2011; Chawla et al 2013) and non-enzymatic antioxidants as phenolics, flavonoids (Munné-Bosch 2005; Gupta and Huang 2014; Rakhmankulova et al 2015; Talbi et al 2015). CAT is involved in scavenging of H 2 O 2 during salt stress and other abiotic stress conditions (Willekens et al 1997) and is considered as a major enzyme detoxifying H 2 O 2 in tomato fruits (Murshed et al 2014). Although APX performs the same general function as catalase, it catalyzes removal of H 2 O 2 by using ascorbate as a reductant.…”

iTRAQ-Based Protein Profiling Provides Insights into the Mechanism of Light-Induced Anthocyanin Biosynthesis in Chrysanthemum (Chrysanthemum × morifolium)

“…A study on petunia demonstrated that anthocyanin biosynthetic enzyme CHS, TF PH4, and signaltransducing protein CONSTANS are key proteins that affect the light-induced pigmentation of petunia flower; a consistent expression pattern between related genes and proteins was found [43]. Most recently, CHI, F3H, and 3GT were found as cor-DEGs-DEPs in eggplant (Solanum melongena) in response to light [39], indicating that they might play a broad and important role in the dark to light transition.…”