Conservation and Diversification of Floral Homeotic MADS-box Genes in Eustoma grandiflorum

Abstract

The MADS-box gene family is one of the largest transcription factor gene families in plants and is necessary at various developmental stages. Many studies on flower development show that especially MIKC c -type MADSbox genes are essential for proper floral organ development. We identified and characterized MIKC c -type MADS-box genes expressed in Eustoma grandiflorum flowers. Twenty-three genes were identified and grouped into 10 clades, which were characterized by conserved specific motifs. Phylogenetic analysis indicated the diversification of AG/PLE, AP3/DEF, PI/GLO, and SEP clades and the occurrence of recent gene duplication events. The floral organ-specific expression patterns were partly diversified within the gene members of AP3/DEF and SEP clades, while they were conserved in AG/PLE and PI/GLO clades. These results suggest that genes with conserved expression as well as those with diversified expression contribute to specifying floral organ identity in E. grandiflorum.

Isolation and characterization of the C-class MADS-box gene involved in the formation of double flowers in Japanese gentian

“…AP3/DEF genes belonging to the euAP3 ( GsAP3a and GsAP3b ) and TM6 ( GsTM6 ) groups were isolated from Japanese gentian (Additional file 1 : Figure S2). Three euAP3 , one TM6 , and two PI/GLO genes were also identified from Eustoma grandiflorum in the family Gentianaceae [ 27 ]. Therefore, it seems that a TM6 gene encoding a B-class MADS-box protein is present in the family Gentianaceae, but not in the Solanaceae [ 35 ] or Asteraceae [ 49 ].…”

“…In this study, we could not find any paralogous genes belonging to the AG/FAR subgroup by degenerate PCR technology. In E. grandiflorum , which also belongs to the family Gentianaceae, three SHP / PLE subgroup genes ( EgPLE1 to EgPLE3 ) were identified, but no AG / FAR subgroup genes [ 27 ]. The AG/FAR subgroup of C-class MADS-box genes is responsible for male and female organ identity in several plant species.…”

“…However, there have been few studies on the floral morphogenesis in Japanese gentian at the molecular level. Floral homeotic MADS-box genes have been isolated and characterized from E. grandiflorum , which belongs to the family Gentianaceae [ 27 ]. Although Mishiba et al [ 28 ] isolated four MADS-box genes from G. triflora ( GtMADS1 – GtMADS4 ; Genbank accession numbers AB189429–AB189432), these genes have not been characterized in detail.…”

Thermal Control Suitable for Increasing Petals in <i>Eustoma grandiflorum</i> (Raf.) Shinn.

“…In double-flowered Eustoma, there is no homeotic conversion from stamens into petals, suggesting that it is not caused by a loss-of-function mutation in the class C gene, although the expression pattern of class C genes of Eustoma follow the ABC model of Arabidopsis (Ishimori and Kawabata, 2014). The fluctuation in the petal number due to temperature has been observed in other species, such as roses, carnations, and cyclamen (Garrod and Harris, 1974;Ma et al, 2015;.…”

Development of an SSR marker-based genetic linkage map and identification of a QTL associated with flowering time in <i>Eustoma</i>

“…Forms with spectacular flowers are grown worldwide and are commercially relevant as cut flowers. In response to the commercial success of E. grandiflorum, studies on traits, such as corolla color, floral morphology, and heat tolerance of the rosette, have been conducted (Ishimori and Kawabata 2014, Ohkawa et al 1991, Pergola et al 1992, Shimizu et al 2011. Approaches for genetic modification of E. grandiflorum have been explored, which are undeniably useful for functional analysis (Azuma et al 2016, Chanoca et al 2015, Nakano 2017, Nielsen et al 2002.…”