Assessing the role of SlBBXs in tomato fruit cuticle biosynthesis and deposition

• Grant number: 24/13844-7
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: October 01, 2024
• End date: September 30, 2026
• Field of knowledge: Biological Sciences - Botany - Pant Physiology
• Principal Investigator: Luciano Freschi
• Grantee: Bruna Orsi
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 23/03330-3 - Light and stress signal transduction pathways: how to optimize multiple responses for improving crop yield and quality, AP.TEM

Abstract

The cuticle contributes in multiple ways to the adaptation of plants under different environmental conditions. In fleshy fruits, such as tomatoes (Solanum lycopersicum), the control of cuticle formation is highly relevant to both fruit physiology and agronomic/commercial aspects. Recently, studies carried out on A. thaliana plants and maize leaves have demonstrated a possible activation of genes involved in cuticle biosynthesis in response to phytochrome (PHY)-dependent light stimuli perception, with consequences for the cuticular wax biosynthesis and deposition in vegetative tissues. However, the role of light signaling in controlling cuticle formation in fleshy fruits remains elusive. Among the transcription factors involved in light signaling, the BBX proteins have received increasing attention recently due to their involvement in various developmental processes. Therefore, this project aims to characterize the possible roles played by selected SlBBXs on the regulation of tomato fruit cuticle biogenesis, structure and composition, and its impacts on fruit desiccation and postharvest shelf life. To investigate these interactions, we propose to: (1) characterize the involvement of SlBBX17/20/24/26/29 on cuticle formation via genetic approaches (mutants and transgenics), (2) identify cuticle formation-related genes regulated by the SlBBXs through gene expression profiling and other molecular biology approaches. The project will utilize tomato mutants and transgenic lines already available in our laboratory, whose ripe fruits will be used to comprehensively analyze cuticle composition and structure, postharvest water loss and resistance to pathogen attack. Moreover, immature green and breaker fruits will be used to assess the expression profile of key genes related to cuticle formation and deposition. By using these approaches, we expect to generate comprehensive knowledge about the role of SlBBX signaling on the cuticle formation in fleshy fruits, which may facilitate identifying new biotechnological alternatives to minimize the economic losses caused by losses due to excessive postharvest water loss and rotting during production and transport of these fruits.