Integrating circadian and gibberellin signaling in Arabidopsis: possible links between the circadian clock and the AtGID1 transcription

Whole-transcriptome analysis of differentially expressed genes in the mutant and normal capitula of Chrysanthemum morifolium

BACKGROUND

Chrysanthemum morifolium is one of the most economically important and popular floricultural crops in the family Asteraceae. Chrysanthemum flowers vary considerably in terms of colors and shapes. However, the molecular mechanism controlling the development of chrysanthemum floral colors and shapes remains an enigma. We analyzed a cut-flower chrysanthemum variety that produces normal capitula composed of ray florets with normally developed pistils and purple corollas and mutant capitula comprising ray florets with green corollas and vegetative buds instead of pistils.

RESULTS

We conducted a whole-transcriptome analysis of the differentially expressed genes (DEGs) in the mutant and normal capitula using third-generation and second-generation sequencing techniques. We identified the DEGs between the mutant and normal capitula to reveal important regulators underlying the differential development. Many transcription factors and genes related to the photoperiod and GA pathways, floral organ identity, and the anthocyanin biosynthesis pathway were differentially expressed between the normal and mutant capitula. A qualitative analysis of the pigments in the florets of normal and mutant capitula indicated anthocyanins were synthesized and accumulated in the florets of normal capitula, but not in the florets of mutant capitula. These results provide clues regarding the molecular basis of the replacement of Chrysanthemum morifolium ray florets with normally developed pistils and purple corollas with mutant ray florets with green corollas and vegetative buds. Additionally, the study findings will help to elucidate the molecular mechanisms underlying floral organ development and contribute to the development of techniques for studying the regulation of flower shape and color, which may enhance chrysanthemum breeding.

CONCLUSIONS

The whole-transcriptome analysis of DEGs in mutant and normal C. morifolium capitula described herein indicates the anthocyanin deficiency of the mutant capitula may be related to the mutation that replaces ray floret pistils with vegetative buds. Moreover, pistils may be required for the anthocyanin biosynthesis in the corollas of chrysanthemum ray florets.

Whole-transcriptome analysis of differentially expressed genes in the mutant and normal capitula of Chrysanthemum morifolium

BACKGROUND

Chrysanthemum morifolium is one of the most economically important and popular floricultural crops in the family Asteraceae. Chrysanthemum flowers vary considerably in terms of colors and shapes. However, the molecular mechanism controlling the development of chrysanthemum floral colors and shapes remains an enigma. We analyzed a cut-flower chrysanthemum variety that produces normal capitula composed of ray florets with normally developed pistils and purple corollas and mutant capitula comprising ray florets with green corollas and vegetative buds instead of pistils.

RESULTS

We conducted a whole-transcriptome analysis of the differentially expressed genes (DEGs) in the mutant and normal capitula using third-generation and second-generation sequencing techniques. We identified the DEGs between the mutant and normal capitula to reveal important regulators underlying the differential development. Many transcription factors and genes related to the photoperiod and GA pathways, floral organ identity, and the anthocyanin biosynthesis pathway were differentially expressed between the normal and mutant capitula. A qualitative analysis of the pigments in the florets of normal and mutant capitula indicated anthocyanins were synthesized and accumulated in the florets of normal capitula, but not in the florets of mutant capitula. These results provide clues regarding the molecular basis of the replacement of Chrysanthemum morifolium ray florets with normally developed pistils and purple corollas with mutant ray florets with green corollas and vegetative buds. Additionally, the study findings will help to elucidate the molecular mechanisms underlying floral organ development and contribute to the development of techniques for studying the regulation of flower shape and color, which may enhance chrysanthemum breeding.

CONCLUSIONS

The whole-transcriptome analysis of DEGs in mutant and normal C. morifolium capitula described herein indicates the anthocyanin deficiency of the mutant capitula may be related to the mutation that replaces ray floret pistils with vegetative buds. Moreover, pistils may be required for the anthocyanin biosynthesis in the corollas of chrysanthemum ray florets.

AthaMap web tools for the analysis of transcriptional and posttranscriptional regulation of gene expression in Arabidopsis thaliana

The AthaMap database provides a map of verified and predicted transcription factor (TF) and small RNA-binding sites for the A. thaliana genome. The database can be used for bioinformatic predictions of putative regulatory sites. Several online web tools are available that address specific questions. Starting with the identification of transcription factor-binding sites (TFBS) in any gene of interest, colocalizing TFBS can be identified as well as common TFBS in a set of user-provided genes. Furthermore, genes can be identified that are potentially targeted by specific transcription factors or small inhibitory RNAs. This chapter provides detailed information on how each AthaMap web tool can be used online. Examples on how this database is used to address questions in circadian and diurnal regulation are given. Furthermore, complementary databases and databases that go beyond questions addressed with AthaMap are discussed.