Assessing the role of SlBBXs in shade avoidance and biotic stress

• Grant number: 24/12977-3
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: January 01, 2025
• End date: May 31, 2026
• Field of knowledge: Biological Sciences - Botany - Pant Physiology
• Principal Investigator: Maria Magdalena Rossi
• Grantee: Juliene dos Reis Moreira
• 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
• Associated scholarship(s): 25/08851-7 - Growth vs Defense: Unraveling the Molecular Players in Tomato Trade-Off Mechanisms, BE.EP.PD

Abstract

Among the plethora of environmental stimuli to which plants are exposed, biotic interactions, such as with pathogens,herbivores, or beneficial microorganisms, trigger the modulation of complex signaling cascades mediated by several plant hormones. Particularly, jasmonic acid (JA) is a core component in the response network to wounding, herbivory and necrotrophic pathogens. In the absence of stimuli, JASMONIC ZIM-DOMAIN PROTEINS (JAZs) occur in the nucleus, creating a repressive complex together with NINJA and TOPLESS, which inhibits JA response by attenuating the activity of the MYC2 transcription fator. When triggered, JA is synthesized and translocated to the nucleus, where it interacts with the SKP/CULLIN/F-BOX - CORONATINE INSENSITIVE 1 (SCF-COI1) E3 UBIQUITIN LIGASE complex that induces the ubiquitination and,consequently, degradation of JAZ proteins, alleviating the repression over MYC2 and thus, triggering the expression of JA responsive genes. It is well described a negative crosstalk between growth and defense; which, classically, was explained as a matter of resource allocation. This hypothesis has been challenged recently by the characterization of molecular mechanisms that control the trade-off between defense and growth in which several critical points between light and JA signaling pathways have been identified in Arabidopsis thaliana model species. Interestingly, recent evidence indicates a role for the BBX protein family in the interplay between light and JA signal transduction. Thus, the role of BBXs as a hub controlling the growth-defense trade-off is promising, yet poorly explored up todate. In this context, the project aims to investigate the role of SlBBX proteins in growth-defense crosstalk in tomato crop.