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Lira, B. S.

Publications and source records attributed to Lira, B. S..

2 recordsLinked to original sources

SELF PRUNING 3C is a flowering repressor that modulates seed germination, root architecture and drought responses

Allelic variation in the CETS (CENTRORADIALIS, TERMINAL FLOWER 1, SELF PRUNING) gene family has been shown to control agronomically important traits in many crops. CETS genes encode phosphatidylethanolamine binding proteins (PEBPs) that have a central role in flowering time control as florigenic and anti-florigenic signals. The great expansion of CETS genes in many species suggests that the functions of this family go beyond flowering. Here, we characterize the tomato SELF PRUNING 3C (SP3C) gene, and show that besides acting as a flowering repressor it also regulates seed germination and modulates root architecture. We show that loss of SP3C function in CRISPR/Cas9-generated mutant lines accelerates seed germination and increases root length with lower root side branching. Higher SP3C expression in transgenic lines promotes the opposite effects and also improves tolerance to water stress in seedlings. These discoveries provide insights into the role of SP paralogs in agronomically relevant traits and support future exploration of the involvement of CETS genes in abiotic stress responses. HighlightThe SELF PRUNING 3C (SP3C) gene is a repressor of flowering in tomato and exhibits additional functions, acting as a repressor of seed germination and modulating root architecture.

molecular biology↗

Auxin-driven ecophysiological diversification of leaves in domesticated tomato

Heterobaric leaves have bundle sheath extensions (BSEs) that compartmentalise the parenchyma, whereas homobaric leaves do not. The presence of BSEs affects leaf hydraulics and photosynthetic rate. The tomato (Solanum lycopersicum) obscuravenosa (obv) mutant lacks BSEs. Here we identify the obv gene and the causative mutation, a non-synonymous amino acid change that disrupts a C2H2 zinc finger motif in a putative transcription factor. This mutation exists as a rare polymorphism in the natural range of wild tomatoes, but has increased in frequency in domesticated tomatoes, suggesting that the latter diversified into heterobaric and homobaric leaf types. The obv mutant displays reduced vein density, leaf hydraulic conductance and photosynthetic assimilation rate. We show that these and other effects on plant development, including changes in leaf insertion angle, leaf margin serration, minor vein density and fruit shape, are controlled by OBV via changes in auxin signalling. Loss of function of the transcriptional regulator AUXIN RESPONSE FACTOR (ARF4) also results in defective BSE development, revealing an additional component of a novel genetic module controlling aspects of leaf development important for ecological adaptation and subject to breeding selection. One sentence summarydistribution of tomato heterobaric and homobaric leaves is controlled by a single-nucleotide polymorphism in an auxin-related transcription factor

plant biology↗