terclim by ICS banner
IVES 9 IVES Conference Series 9 VviSOC1a and VviAG1 act antagonistically in the regulation of flower formation

VviSOC1a and VviAG1 act antagonistically in the regulation of flower formation

Abstract

The SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1) is a key floral activator that coordinates external and internal stimuli to ensure timely flowering. During early stages of flower formation, SOC1 represses floral organ identity genes such as AGAMOUS (AG) to prevent premature organ differentiation. In addition to floral organ specification, AG has been shown to regulate fleshy fruit expansion and ripening and, as such, is an important contributor to fruit quality traits. Currently, little is known about the function and gene regulatory network of the grapevine homologs VviSOC1a and VviAG1. As such, the aim of this study was to functionally characterise both genes by overexpressing them in tomato and performing phenotypic and gene expression studies. A dual luciferase (DL) assay involving putative target gene promoters was also conducted. Overexpression of VviSOC1a led to the development of leaf-like sepals, petals with increased chlorophyll content and plant sterility phenotypes. VviAG1-OE lines displayed hastened floral initiation, stamenoid petals, dwarfed fruit, as well as forming fleshy fruit sepals which gave the appearance of ripened pericarp tissue. The observed floral phenotypes were, in part, supported by the modulation of genes required for floral organ specification in tomato. VviSOC1a and VviAG1 displayed opposite expression trends, while also repressing each other’s expression in the DL assay. Collectively, the findings of this study supported a role for VviSOC1a in regulating floral organ specification, through the repression of the stamen and carpel identity gene VviAG1. An additional function for VviAG1 in berry development and ripening is also suggested.

Download the abstract

DOI:

Publication date: June 13, 2024

Issue: Open GPB 2024

Type: Poster

Authors

Jenna Jolliffe1,2, Claudio Moser2, Stefania Pilati2 and Justin Lashbrooke3*

1South African Grape and Wine Research Institute, Stellenbosch University, Stellenbosch, 7600, South Africa
2Research and Innovation Centre, Edmund Mach Foundation, San Michele all’Adige, 38098, Italy
3Department of Genetics, Stellenbosch University, Stellenbosch, 7600, South Africa

Contact the author*

Keywords

SOC1, AG1, Flower, transcription factor, development

Tags

IVES Conference Series | Open GPB | Open GPB 2024

Citation

Related articles…

Short-term canopy strategies to enhance grapevine adaptation to climate change

Context and purpose of the study – Viticulture faces significant challenges due to climate change, with increased frequency of extreme weather events impacting grapevine growth, grape quality, and wine production.

Read More

Two dimensions, one mission: unlocking grape composition by GC × GC

Aroma is one of the most important attributes that determine consumer’s perception of the sensory quality of wine and varietal typicity.

Read More

Effect of different canopy managements on microclimate and carbon allocation in Vitis vinifera cv Chardonnay

Climate change strongly affects the wine-growing sector which increasingly requires in situ adaptation strategies aimed at preserving the sustainability of production. Investigating microclimate becomes crucial in comprehending environmental pressures on plants. The microclimatic investigation conducted in the Orvieto PDO (central Italy) allowed us to highlight the climatic dynamics occurring in the last 25 years and the frequency and intensity of abiotic stresses. Two management strategies for the canopy were identified: early defoliation (ELR) and foliar application of Basalt Flour ® (FB) compared to the ordinary management (C) of the company (bud selection and topping). The effects on plant vigour indices (LAI), resource allocation in terms of carbon stored in the above-ground organs of the vine, and the microclimate of the canopy and the berry were evaluated. In particular, microclimate was evaluated through a network of sensors connected wirelessly (Wireless Sensor Network), dedicated to collecting information on temperature and humidity in the canopy and clusters.

Read More

The role of soil water holding capacity and plant water relations in zone/terroir expression

The spatial variability in soil type and depth and water holding capacity is very high in many viticultural regions of the world. Differences in rooting depths and water extraction profiles and their seasonal dynamics add additional variability and it is extremely difficult to deduct direct causal relationships between these factors and fruit

Read More

The use of fluorescence spectroscopy to develop a variability index and measure grape heterogeneity

AIM This work aims to investigate fluorescence spectroscopy as a tool to assess grape homogenates to discriminate between samples of varying maturities and to develop an index to objectively characterise the level of grape heterogeneity present in any given vineyard.

Read More