Generation of expressed sequence tags for discovery of genes responsible for floral traits of Chrysanthemum morifolium by next-generation sequencing technology

Abstract

Background Chrysanthemum morifolium is one of the most economically valuable ornamental plants worldwide. Chrysanthemum is an allohexaploid plant with a large genome that is commercially propagated by vegetative reproduction. New cultivars with different floral traits, such as color, morphology, and scent, have been generated mainly by classical cross-breeding and mutation breeding. However, only limited genetic resources and their genome information are available for the generation of new floral traits.ResultsTo obtain useful information about molecular bases for floral traits of chrysanthemums, we read expressed sequence tags (ESTs) of chrysanthemums by high-throughput sequencing using the 454 pyrosequencing technology. We constructed normalized cDNA libraries, consisting of full-length, 3′-UTR, and 5′-UTR cDNAs derived from various tissues of chrysanthemums. These libraries produced a total number of 3,772,677 high-quality reads, which were assembled into 213,204 contigs. By comparing the data obtained with those of full genome-sequenced species, we confirmed that our chrysanthemum contig set contained the majority of all expressed genes, which was sufficient for further molecular analysis in chrysanthemums.ConclusionWe confirmed that our chrysanthemum EST set (contigs) contained a number of contigs that encoded transcription factors and enzymes involved in pigment and aroma compound metabolism that was comparable to that of other species. This information can serve as an informative resource for identifying genes involved in various biological processes in chrysanthemums. Moreover, the findings of our study will contribute to a better understanding of the floral characteristics of chrysanthemums including the myriad cultivars at the molecular level.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-017-4061-3) contains supplementary material, which is available to authorized users.

The Chrysanthemum nankingense Genome Provides Insights into the Evolution and Diversification of Chrysanthemum Flowers and Medicinal Traits

“…Our finding that there are seven CYC2-like genes in C. nankingense further supports this observation (Supplemental Figure 8). Moreover, multiple CCD4a gene copies are found in cultivated chrysanthemum genomes but not in the C. nankingense progenitor genome, which indicates that the CCD4a genes contribute to the white color formation in chrysanthemum petals (Ohmiya et al, 2006;Sasaki et al, 2017) and suggests that the evolution of this gene clade is linked to a recent polyploidy event in cultivated chrysanthemums.…”

Molecular mechanisms underlying the diverse array of petal colors in chrysanthemum flowers

“…The mechanism of chlorophyll accumulation in leaves has been well studied, whereas less attention has been paid to that in flowers. Recently, an expressed sequence tag database of chrysanthemum cultivar ‘Sei-Marine’ was constructed ( Sasaki et al 2017 ). Based on the database, Ohmiya et al (2017) generated a custom array and performed microarray analyses.…”

Investigation of Differences in Fertility among Progenies from Self-Pollinated Chrysanthemum

“…Unigene sequences were aligned by Blastx to protein databases such as NR (NCBI nonredundant protein), Swiss-Prot, KEGG (Kyoto Encyclopedia of Genes and Genomes) and COG (Cluster of Orthologous Groups) and aligned by Blastn to the nucleotide database NT ( E -value < 0.00001). In addition, we used Blast2 GO program [ 58 ] to obtain GO (Gene Ontology) [ 41 ] annotation of unigenes. GO has three ontologies describing molecular function, cellular component and biological process.…”