14-3-3 Proteins Are Involved in BR-Induced Ray Petal Elongation in Gerbera hybrida

Abstract

14-3-3 proteins play a major role in the regulation of primary metabolism, protein transport, ion channel activity, signal transduction and biotic/abiotic stress responses. However, their involvement in petal growth and development is largely unknown. Here, we identified and characterized the expression patterns of seven genes of the 14-3-3 family in gerbera. While none of the genes showed any tissue or developmental specificity of spatiotemporal expression, all seven predicted proteins have the nine α-helices typical of 14-3-3 proteins. Following treatment with brassinolide, an endogenous brassinosteroid, the Gh14-3-3 genes displayed various response patterns; for example, Gh14-3-3b and Gh14-3-3f reached their highest expression level at early (2 h) and late (24 h) timepoints, respectively. Further study revealed that overexpression of Gh14-3-3b or Gh14-3-3f promoted cell elongation, leading to an increase in ray petal length. By contrast, silencing of Gh14-3-3b or Gh14-3-3f inhibited petal elongation, which was eliminated partly by brassinolide. Correspondingly, the expression of petal elongation-related and brassinosteroid signaling-related genes was modified in transgenic petals. Taken together, our research suggests that Gh14-3-3b and Gh14-3-3f are positive regulators of brassinosteroid-induced ray petal elongation and thus provides novel insights into the molecular mechanism of petal growth and development.

A regulatory GhBPE-GhPRGL module maintains ray petal length in Gerbera hybrida

“…The transient transformation of ray petals was conducted as described in other recent studies (Han et al, 2017 ; Huang et al, 2020 ; Lin et al, 2021 ). The full CDSs of GhPRGL and GhBPE were cloned into the pCanG vector to generate the overexpression (OE) vectors pCanG-GhPRGL and pCanG-GhBPE, respectively, while the virus-induced gene silencing (VIGS) vectors pTRV2-GhPRGL and pTRV2-GhBPE were similarly introduced into pTRV2.…”

Phenotypic Variation in Flower Color and Morphology in the Gerbera (Gerbera hybrida) F1 Hybrid Population and Their Association with EST-SSR Markers

“…For outer corolla lips, 'LSB' was split, 'GMZ' was ligulate, and among the hybrid offspring, 71 were ligulate, and 69 were split (Figure 2K and Table S3). For the ray floret color, 'LSB' was white, 'GMZ' was red-purple, and the hybrid offspring could be categorized into eight colors: white (1), yellow-green (1), yellow (8), yellow-orange (6), orange (9), orange-red (6), red (69), and red-purple (41), with red and red-purple accounting for the majority (78.57%) (Figure 2L and Table S3).…”

“…The flowers display a broad spectrum of colors, including white, yellow, orange, pink, red, and purple, and exhibit various unique morphologies, such as the patterning of the ray, disk florets, and a distinctive petal trait known as “split ray floret”. This diversity positions gerbera as an ideal model for studying flower color and morphology [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ]. However, research on the color and split ray floret traits of gerbera is currently limited, which restricts the directional breeding of this species.…”

Stigma/Style Cell-Cycle Inhibitor 1, a Regulator of Cell Proliferation, Interacts With a Specific 14-3-3 Protein and Is Degraded During Cell Division

“…14-3-3 proteins can form homo and heterodimers ( Jones et al, 1995 ; Chaudhri et al, 2003 ), and it has been suggested that each type of dimer could undertake diverse functions ( Paul et al, 2012 ). There is certain specificity in 14-3-3 dimerization and not all homodimers and possible heterodimers are formed ( Pallucca et al, 2014 ; Lin et al, 2021 ). The 14-3-3 dimer can interact with two different sites of a single protein or simultaneously interact with two distinct proteins ( Yaffe, 2002 ; Chevalier et al, 2009 ).…”