Biology subjects

Moyano, T.

Publications and source records attributed to Moyano, T..

5 recordsLinked to original sources

bioRxiv2025

Consistent drought regulation in grapevine is driven by directional transcription factor activity

Climate change is intensifying environmental stresses such as drought, threatening vineyard productivity and sustainability worldwide. Vitis vinifera cultivars, responsible for most wine and table grape production, are particularly sensitive to water deficit, whereas many rootstocks derive from different Vitis species or interspecific hybrids with higher stress tolerance. A key step toward mitigating the effects of severe drought is the identification of regulatory genes controlling drought responses, enabling the design of gene expression-based strategies or the generation of resilient cultivars through new breeding technologies. In this study, we performed a meta-transcriptomic analysis to identify genes consistently differentially expressed under drought in cultivated V. vinifera and two hybrid rootstocks (M4 and 101-14). Using more than twenty drought-control comparisons, we identified a core set of 4,617 drought-responsive genes that were consistently mis regulated across multiple experimental conditions. This core gene set was used to construct gene regulatory networks integrating genome-wide transcription factor (TF) binding motif analysis with random forest-based regulatory network generation employing machine learning techniques. We identified key TFs, including the Abscisic-Acid-(ABA) Responsive Element Binding Factor 2 (ABF2), MYB30A and an uncharacterized HMGbox domain protein, as central regulators within the network. Several top-ranking TFs, displaying up-or down-regulation under drought conditions, were primarily identified as positive regulators of their target genes, while lower-hierarchy TFs exhibited inverse expression relationships with their predicted targets. The network exhibited a hierarchical organization architecture among several TFs whose homologues in other species are linked to ABA signaling, with several TF families represented, each potentially operating at distinct regulatory tiers. Some TFs appear to act as central hubs orchestrating broad transcriptional programs, whereas others likely control more specialized branches of the drought response. Overall, these findings offer novel insights into the transcriptional control of drought tolerance in grapevine and provide key candidate regulators for breeding and biotechnological strategies aimed at improving stress resilience.

plant biology↗

bioRxiv2024

RSL4 regulatory network acts as an early driver of root hair growth at low temperature in Arabidopsis thaliana

The root hair (RH) cells can elongate to several hundred times their initial size, and are an ideal model system for investigating cell size control. Their development is influenced by both endogenous and external signals, which are combined to form an integrative response. Surprisingly, a low temperature condition of 10{degrees}C causes an increased RH growth in Arabidopsis and in several monocots, even when the development of the rest of the plant are halted. Previously, we demonstrated a strong correlation between the RH growth response and a significant decrease in nutrient availability in the medium under low temperature conditions. However, the molecular basis responsible for receiving and transmitting signals related to the availability of nutrients in the soil, and their relation to plant development, remain largely unknown. In this study, we have discovered two antagonic gene regulatory networks (GRNs) controlling RH early transcriptome responses to low temperature. One GNR enhances RH growth and it is commanded by the transcription factors (FTs) ROOT HAIR DEFECTIVE 6 (RHD6), HAIR DEFECTIVE 6-LIKE 2 and 4 (RSL2-RSL4) and a member of the homeodomain leucine zipper (HD-Zip I) group I 16 (AtHB16). On the other hand, a second GRN was identified as a negative regulator of RH growth at low temperature and it is composed by the trihelix TF GT2-LIKE1 (GTL1) and the associated DF1, a previously unidentified MYB-like TF (AT2G01060) and several members of HD-Zip I group (AtHB3, AtHB13, AtHB20, AtHB23). Functional analysis of both GRNs highlights a complex regulation of RH growth response to low temperature, and more importantly, these discoveries enhance our comprehension of how plants synchronize the RH growth in response to variations in temperature at the cellular level. Significance StatementRoot hair (RH) cells may expand hundreds of times, making them a useful cell size model. Integrated endogenous and exogenous cues affect their development. Even when plant development ceases, Arabidopsis and other monocots grow RH at 10{degrees}C. We previously established a strong correlation between growth response and a substantial medium nutrition reduction at low temperature. Receiving and transmitting soil nutrient signals and their impact on plant development are unknown molecularly. Our study identified two opposing gene regulatory networks (GRN) that govern early transcriptome responses linked to RH growth at low temperature. Functional analysis shows a complex regulation of the transcriptional cascade to influence the low-temperature RH growth. These results explain how cells coordinate RH formation in response to temperature.

plant biology↗

bioRxiv2020

Transcription factor TGA2 is essential for UV-B stress tolerance controlling oxidative stress in Arabidopsis

Plants possess a diversity of Reactive Oxygen Species (ROS)-processing enzymes involved in sensing and controlling ROS levels under basal and stressful conditions. There is little information on the transcriptional regulators that control the expression of these ROS-processing enzymes, particularly at the onset of the defense response to abiotic stress. Filling this gap, this paper reports a critical role for Arabidopsis TGA class II factors (TGA2, TGA5, and TGA6) in the tolerance response to UV-B light and photooxidative stress, by activating the expression of genes with antioxidative roles. We identified two clusters of genes responsive to UV-B and activated by TGA2/5/6 were identified using RNAseq and clustering analysis. The GSTU gene family, which encodes glutathione transferase enzymes from the Tau subclass, was overrepresented in these clusters. We corroborated the TGA2-mediated activation in response to UV-B for three model genes (GSTU7, GSTU8, and GSTU25) using RT-qPCR and ChIP analyses. Interestingly, using tga256 mutant and TGA2- and GSTU7-complemented mutant plants, we demonstrated that TGA2-mediated induction of GSTU genes is essential to control ROS levels and oxidative damage after UV-B and MeV treatments. This evidence positions TGA class II factors, particularly TGA2, as a key players in the redox signaling network of Arabidopsis plants. HighlightArabidopsis TGA2 transcription factor is part of the redox-signaling network controlling ROS levels and oxidative damage in tolerance response to UV-B and photooxidative stress, via activation of antioxidant GSTU genes.

plant biology↗

bioRxiv2019

Differences in berry primary and secondary metabolisms identified by transcriptomic and metabolic profiling of two table grape color somatic variants

Anthocyanins are flavonoids responsible for the color of berries in skin-pigmented grapevine (Vitis vinifera L.). Due to the widely adopted vegetative propagation of this species, somatic mutations occurring in meristematic cell layers can be fixed and passed into the rest of the plant when cloned. In this study we focused on the transcriptomic and metabolic differences between two color somatic variants. Using microscopic, metabolic and mRNA profiling analyses we compared the table grape cultivar (cv.) Red Globe (RG, with purplish berry skin) and cv. Chimenti Globe (CG, with a contrasting reddish berry skin color). As expected, significant differences were found in the composition of flavonoids and other phenylpropanoids, but also in their upstream precursors shikimate and phenylalanine. Among primary metabolites, sugar phosphates related with sucrose biosynthesis were less accumulated in cv. CG. The red-skinned cv. CG only contained di-hydroxylated anthocyanins (i.e. peonidin and cyanidin) while the tri-hydroxylated derivatives malvidin, delphinidin and petunidin were absent, in correlation to the reddish cv. CG skin coloration. Transcriptomic analysis showed alteration in flavonoid metabolism and terpenoid pathways and in primary metabolism such as sugar content. Eleven flavonoid 35-hydroxylase gene copies were down-regulated in cv. CG. This family of cytochrome P450 oxidoreductases are key in the biosynthesis of tri-hydroxylated anthocyanins. Many transcription factors appeared down-regulated in cv. CG in correlation to the metabolic and transcriptomic changes observed. The use of molecular markers and its confirmation with our RNA-seq data showed the exclusive presence of the null MYBA2 white allele (i.e. homozygous in both L1 and L2 layers) in the two somatic variants. Therefore, the differences in MYBA1 expression seem sufficient for the skin pigmentation differences and the changes in MYBA target gene expression in cv. Chimenti Globe.

plant biology↗

bioRxiv2018

Loop Assembly: a simple and open system for recursive fabrication of DNA circuits

High efficiency methods for DNA assembly are based on sequence overlap between fragments or Type IIS restriction endonuclease cleavage and ligation. These have enabled routine assembly of synthetic DNAs of increased size and complexity. However, these techniques require customisation, elaborate vector sets and serial manipulations for the different stages of assembly. We present Loop assembly, based on a recursive approach to DNA fabrication. Alternate use of two Type IIS restriction endonucleases and corresponding vector sets allows efficient and parallel assembly of large DNA circuits. Plasmids containing standard Level 0 parts can be assembled into circuits containing 1, 4, 16 or more genes by looping between the two vector sets. The vectors also contain modular sites for hybrid assembly using sequence overlap methods. Loop assembly provides a simple generalised solution for DNA construction with standardised parts. The cloning system is provided under an OpenMTA license for unrestricted sharing and open access.

synthetic biology↗