Cloning and Characterization of a cDNA Encoding Sucrose Synthase Associated with Flower Opening through Early Senescence in Carnation (Dianthus caryophyllus L.)

Abstract

Flower opening in carnations (Dianthus caryophyllus L.) is the result of the enlargement of petal cells, which requires sugar metabolism. A cDNA encoding sucrose synthase (DcSUS1) was isolated from carnation petals as a candidate gene acting in the initial step of sugar metabolism in petal cells. DcSUS1 transcripts were detected abundantly in floral tissues of flowering carnation plants; the transcripts accumulated most in the petals and style followed by the ovary, whereas only small accumulation were found in stems, leaves, and calyces. Moreover, nearly constant accumulation of DcSUS1 transcripts was found in the petals during flower opening, fully open, and early senescence periods, whereas decreasing accumulation was detected in petals when senescence progressed. These findings suggested the involvement of DcSUS1 expression in petal cell growth during the opening of carnation flowers.

2,4-Pyridinedicarboxylic Acid Prolongs the Vase Life of Cut Flowers of Spray Carnations

“…The flower-opening process in carnation was separated into 6 stages (Os 1 to Os 6) as described by Harada et al (2010), and the flower senescence process into 4 stages (Ss 1 to Ss 4) as described previously (Morita et al, 2011). Os 6 is the stage at which their outermost petals had just reached right angles to the stems (just fully-open stage).…”

Gibberellin is not Associated with the Enhancing Effect of 2,4-Pyridinedicarboxylic Acid on Flower Opening of ‘Light Pink Barbara’ Carnation

“…We selected DcXTH2 and DcEXPA2 for this analysis since they were associated with petal growth during flower opening (Harada et al, 2011). DcXTH2 is expressed abundantly in petals and its expression is higher at Os3 than at any other stages of the flower opening process.…”

“…After arrival, they were put in plastic containers with their cut end in tap water under continuous light from white fluorescent lamps (14 μmol·m −2 ·s −1 ) at 23°C. The flower opening process was separated into 6 opening stages (Os) and senescence process into 4 senescence stages (Ss) according to Harada et al (2010) and Morita et al (2011), respectively. Ten outermost petals per flower were sampled at the respective stages, and stored at −80°C for extraction of RNA.…”

“…In addition, we analyzed the expression of cell expansion-related genes as markers of the flower opening process. These genes encode proteins involved in cell wall expansion, such as xyloglucan endotransglucosylase/hydrolase (XTH) and expansin, both of which are expressed abundantly in opening flowers of carnation (Harada et al, 2011). Through these analyses, we examined the possibility of the involvement of GA with PDCA action in carnation.…”

Identification and Characterization of Plasma Membrane Intrinsic Protein (PIP) Aquaporin Genes in Petals of Opening Carnation Flowers

“…In order to develop techniques for fine control of flower opening, we need to understand the flower opening process at the molecular level, which includes the identification of the enzymes and proteins functioning in the process. For this purpose, we have been studying the molecular mechanism of flower opening using cut carnations (Dianthus caryophyllus L.) flowers as a model ornamental (Harada et al, 2010Morita et al, 2011). We cloned and characterized several genes expressed during flower opening (Harada et al, 2010Morita et al, 2011).…”