Biology subjects

Peres, L. E. P.

Publications and source records attributed to Peres, L. E. P..

8 recordsLinked to original sources

bioRxiv2026

SELF-PRUNING 5G interplays with age and gibberellin pathways downstream of SlCOL1 to orchestrate photoperiodic tomato flowering

Tomato (Solanum lycopersicum) is classified as a day-neutral plant, whereas its wild relatives exhibit delayed flowering under long day (LD) conditions due to higher activity of the SELF-PRUNING 5G (SP5G). In Arabidopsis thaliana, CONSTANS (CO) activates FLOWERING LOCUS T (FT), a homolog of SP5G, but whether and how CO integrates with SP5G in tomato flowering was unclear. Here, we demonstrate that SlCOL1 (the tomato CO homolog) delays flowering by directly activating SP5G in a PHYTOCHROME B1 (PHYB1)-dependent manner. Importantly, genetic and molecular analyses combining a photoperiod-responsive tomato line carrying the wild SP5G allele from S. pennellii, together with SlCOL1 and flowering-pathway mutants, revealed synergistic crosstalk among the photoperiodic SlCOL1-SP5G module, age-dependent pathway (mediated mainly by the microRNA156-SlSBP module), gibberellin (GA) pathway, and SINGLE FLOWER TRUSS (SFT) pathway. Mechanistically, we show that SP5G forms a complex with miR156-targeted SlSBP13 to directly regulate SFT expression, and that GA may interfere with SP5G activity. Together, these findings revealed a coordinated network that integrates multiple flowering signals to modulate both shared and pathway-specific targets. Our findings provide a significant advance in understanding the molecular regulation of tomato flowering and offer promising avenues for breeding strategies optimized for diverse environmental conditions and latitudes.

plant biology↗

bioRxiv2024

Modulating activity of the APC/C regulator SlSAMBA improves the sugar and antioxidant content of tomato fruits

The Anaphase-Promoting Complex/Cyclosome (APC/C) is an E3 ubiquitin ligase that plays a crucial role in ubiquitin-dependent proteolysis of key cell cycle regulators, which is completed by 26S proteasome. Previously, SAMBA, a plant-specific regulator of the APC/C, was identified in Arabidopsis as a critical factor controlling organ size through the regulation of cell proliferation. Here, by assessing its role in the crop tomato (Solanum lycopersicum), we confirm that SAMBA is a conserved APC/C regulator in plants. Two slsamba genome-edited lines were characterized showing delayed growth, reduced plant size and altered fruit morphology, which were linked to changes in cell division and expansion. Notably, untargeted metabolomics revealed altered flavonoid profiles, along with elevated Brix values in the fruits, indicating a sweeter taste. Accordingly, transcriptomics uncovered a change in temporal gene expression gradients during early fruit development, correlating with the alterations in sugar metabolism and revealing changes in cell wall biosynthesis genes. This study provides the first evidence of SAMBAs role in regulating fruit development, metabolic content, and, ultimately, quality. These important findings offer potential applications for improving the nutritional quality and overall performance of tomato.

plant biology↗

bioRxiv2024

SlAN1 is a limiting factor for the light-dependent anthocyanin accumulation in fruit tissues of purple tomato

Anthocyanins are specialized plant metabolites with significant dietary value due to their anti-inflammatory properties. Research indicates that dietary intake of these phenolic compounds contributes to preventing various chronic diseases. As the most consumed vegetable worldwide, tomato (Solanum lycopersicum) is an excellent candidate for anthocyanin-enrichment strategies. In tomato, activation of anthocyanin biosynthesis is light-dependent, but this mechanism has yet to be entirely characterized. We investigated the role of light in anthocyanin biosynthesis in fruits of the purple tomato, which is a near-isogenic line (NIL) derived from wild accessions into cv. Micro-Tom (MT). MT-Aft/atv/hp2 starts accumulating anthocyanin early during fruit development but is restricted to the peel (exocarp and epicarp). Manipulating light incidence in different fruit tissues determined that the absence of anthocyanin accumulation in the flesh results from the sun-blocking effect of the cyanic epicarp on the mesocarp, thus preventing light from penetrating deeper into the fruit. Transcriptional analyses of the fruit peel and flesh revealed that the bHLH transcription factor SlAN1 (Solyc09g065100) is the limiting factor for light-dependent anthocyanin accumulation in both tissues. This research enhances our comprehension of the genetic and environmental regulation of anthocyanin accumulation in fruit tissues, offering valuable insights into plant breeding for human nutrition. HighlightThe expression of the SlAN1 gene is activated in response to light signals, and it is the limiting factor for anthocyanin pigmentation in tomato fruit tissues.

plant biology↗

bioRxiv2023

Woolly mutation with Get02 locus overcomes the polygenic nature of trichome-based pest resistance in tomato

Type-IV glandular trichomes, which only occur in the juvenile phase of tomato development, produce acylsugars (AS) that broadly protect against arthropod herbivory. Previously, we introgressed the capacity to retain type-IV trichomes in the adult phase from Solanum galapagense into the cv. Micro-Tom (MT). The resulting MT-Get line contained five loci associated with enhancing the density of type-IV trichomes in adult plants. We genetically dissected MT-Get and obtained a sub-line containing only the locus on chromosome 2 (MT- Get02). This genotype displayed about half the density of type-IV trichomes compared to the wild progenitor. However, when we stacked the gain-of-function allele of WOOLLY, which codes for a HD-ZIP IV transcription factor, MT-Get02/Wo exhibited double the number of type-IV trichomes compared to S. galapagense. This discovery corroborates previous reports positioning WOOLLY as a master regulator of trichome development. AS levels in MT-Get02/Wo were comparable to the wild progenitor, although the composition of AS types differed, especially regarding less AS with medium-length acyl chains. Agronomical parameters of MT-Get02/Wo, including yield, were comparable to MT. Pest resistance assays showed enhanced protection against whitefly, caterpillar, and the fungus Septoria lycopersici. However, resistance levels did not reach that of the wild progenitor, suggesting the specificity of particulars AS types in the pest resistance mechanism. Our findings in trichome-mediated resistance advance the development of robust, naturally resistant tomato varieties, harnessing the potential of natural genetic variation. Moreover, by manipulating only two loci, we achieved exceptional results for a highly complex, polygenic trait, such as herbivory resistance in tomato.

plant biology↗

bioRxiv2022

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↗

bioRxiv2020

Genetic factors outside the metabolic cluster for plastid-derived sesquiterpenes are required to pursuit arthropod-resistant tomatoes

To deal with arthropod pests the tomato wild relatives produce a variety of defense compounds in their glandular trichomes. In Solanum habrochaites LA1777, a functional cluster of genes on chromosome 8 controls plastid-derived sesquiterpene synthesis not found in cultivated tomatoes. The main genes at the cluster are Z-prenyltransferase (zFPS) that produces Z-Z-farnesyl diphosphate (Z,Z-FPP), and Santalene and Bergamotene Synthase (SBS) that uses Z,Z-FPP to produce -santalene, {beta}-bergamotene, and -bergamotene in type-VI glandular trichomes. Both LA1777 and cultivated tomatoes have type-VI trichomes, but the gland in cultivated tomato is much smaller containing low levels of monoterpenes and cytosolic-derived sesquiterpenes, which do not provide tomato with the same pest resistance as in LA1777. We successfully transferred the plastid-derived sesquiterpene pathway from LA1777 to type-VI trichomes of a cultivated tomato (cv. Micro-Tom, MT) by a back-crossing approach. The trichomes of the introgressed line named MT-Sesquiterpene synthase 2 (MT-Sst2) produced even higher levels of -santalene, {beta}-bergamotene, and -bergamotene than the type-VI glandular trichomes of LA1777. We also noticed that the type-VI trichome internal storage-cavity size increases in MT-Sst2, probably as an "inflated balloon" effect of the increased amount of sesquiterpenes. Surprisingly, the presence of high amounts of plastid-derived sesquiterpenes was not sufficient to confer resistance to various tomato pests in MT-Sst2. Since MT-Sst2 made the same sesquiterpenes as LA1777, this points to additional factors, outside the genomic region thought to be the metabolic cluster, necessary to obtain arthropod-resistant tomatoes. Our results also provide a better understanding of the morphology of S. habrochaites type-VI trichomes. One-sentence summaryCultivated tomatoes harboring the plastid-derived sesquiterpenes from S. habrochaites need additional genetic components necessary to convert them into effective insecticides.

plant biology↗

bioRxiv2020

The Lanata trichome mutation increases stomatal conductance and reduces leaf temperature in tomato

Background and aimsTrichomes are epidermal structures with an enormous variety of ecological functions and economic applications. Glandular trichomes produce a rich repertoire of secondary metabolites, whereas non-glandular trichomes create a physical barrier against biotic and abiotic stressors. Intense research is underway to understand trichome development and function and enable breeding of more resilient crops. However, little is known on how enhanced trichome density would impinge on leaf photosynthesis, gas exchange and energy balance. MethodsPrevious work has compared multiple species differing in trichome density, instead here we analyzed monogenic trichome mutants in a single tomato genetic background (cv. Micro-Tom). We determined growth parameters, leaf spectral properties, gas exchange and leaf temperature in the hairs absent (h), Lanata (Ln) and Woolly (Wo) trichome mutants. Key resultsShoot dry mass, leaf area, leaf spectral properties and cuticular conductance were not affected by the mutations. However, the Ln mutant showed increased carbon assimilation (A) possibly associated with higher stomatal conductance (gs), since there were no differences in stomatal density or stomatal index between genotypes. Leaf temperature was furthermore reduced in Ln in the early hours of the afternoon. ConclusionsWe show that a single monogenic mutation can increase glandular trichome density, a desirable trait for crop breeding, whilst concomitantly improving leaf gas exchange and reducing leaf temperature. HIGHLIGHTA monogenic mutation in tomato increases trichome density and optimizes gas exchange and leaf temperature

plant biology↗

bioRxiv2017

Bundle sheath extensions in tomato affect leaf phenotypic plasticity in response to irradiance

Coordination between structural and physiological traits is key to plants responses to environmental fluctuations. In heterobaric leaves, bundle sheath extensions (BSEs) increase photosynthetic performance (light-saturated rates of photosynthesis, Amax) and water transport capacity (leaf hydraulic conductance, Kleaf). However, it is not clear how BSEs affect these and other leaf developmental and physiological parameters in response to environmental conditions. The obscuravenosa (obv) mutation, found in many commercial tomato varieties, leads to absence of BSEs. We examined structural and physiological traits of tomato heterobaric and homobaric (obv) near-isogenic lines (NILs) grown at two different irradiance levels. Kleaf, minor vein density and stomatal pore area index decreased with shading in heterobaric but not in homobaric leaves, which show similarly lower values in both conditions. Homobaric plants, on the other hand, showed increased Amax, leaf intercellular air spaces and mesophyll surface area exposed to intercellular airspace (Smes) in comparison with heterobaric plants when both were grown in the shade. BSEs further affected carbon isotope discrimination, a proxy for long-term water-use efficiency. BSEs confer plasticity in traits related to leaf structure and function in response to irradiance levels and might act as a hub integrating leaf structure, photosynthetic function and water supply and demand.\n\nSummary statementThe presence of bundle sheath extension (BSEs) defines leaves as heterobaric, as opposed to homobaric leaves that lack them. Multiple functions have been proposed for BSEs, but their impact on different environmental conditions is still unclear. Here, we compared a tomato (Solanum lycopersicum) homobaric mutant lacking BSEs with its corresponding heterobaric wild-type, grown under two irradiance conditions. We show that the presence of BSEs differentially alters various physiological and anatomical parameters in response to growth irradiance. We propose that BSEs could act as hubs coordinating leaf plasticity in response to environmental factors.\n\nArticle typeResearch article

plant biology↗