Biology subjects

Prat, S.

Publications and source records attributed to Prat, S..

10 recordsLinked to original sources

bioRxiv2026

Potato yield can be predicted by using drone-captured and environmental measurements early in the growing season

Accurate pre-harvest prediction of crop yield informs variety selection, optimizes management, and accelerates breeding. As potato is the worlds leading non-grain staple, here we evaluate a diverse panel of varieties in a three-year field trial across five European locations. Canopy development and environmental parameters are monitored throughout the growing season using drone-based imaging, in-field sensors and gene expression measurements, while tuber yield and quality traits are quantified at harvest. We show that these data enable the identification of climate-resilient, high-yielding genotypes and support the development of machine learning models that explain over 80% of yield variation in independent test sets. Strikingly, measurements collected within the first two months after planting achieve predictive performance comparable to models trained on full-season data. Model interrogation further shows that over 70% of yield variation can already be predicted based on a simple five-parameter linear equation. Our framework thus demonstrates the potential of integrative field phenotyping and data-driven modeling to improve variety selection across heterogeneous environments.

plant biology↗

bioRxiv2023

Linking the evolution of two prefrontal brain regions to social and foraging challenges in primates

The diversity of cognitive skills across primates remains both a fascinating and a controversial issue. Recent comparative studies provided conflicting results regarding the contribution of social vs ecological constraints to the evolution of cognition. Here, we used an interdisciplinary approach combining comparative cognitive neurosciences and behavioral ecology. Using brain imaging data from 16 primate species, we measured the size of two prefrontal brain regions, the frontal pole (FP) and the dorso-lateral prefrontal cortex (DLPFC), respectively involved in metacognition and working memory, and examined their relation to a combination of socio-ecological variables. The size of these prefrontal regions, as well as the whole brain, was best explained by three variables: body mass, daily traveled distance (an index of ecological constraints) and population density (an index of social constraints). The strong influence of ecological constraints on FP and DLPFC volumes suggests that both metacognition and working memory are critical for foraging in primates. Interestingly, FP volume was much more sensitive to social constraints than DLPFC volume, in line with laboratory studies showing an implication of FP in complex social interactions. Thus, our data highlights the relative weight of social vs ecological constraints on the evolution of specific prefrontal brain regions and their associated cognitive operations in primates. FundingThis work was supported by recurrent funding from CNRS to SB, SP and CG. It was also supported by the ANR-17-CE27-0005 (HOMTECH).

neuroscience↗

bioRxiv2022

A mini-TGA protein, lacking a functional DNA-binding domain, modulates gene expression through heterogeneous association with transcription factors

TGA transcription factors, which bind their target DNA through a conserved basic region leucine zipper (bZIP) domain, are vital regulators of gene expression in salicylic acid (SA)-mediated plant immunity. Here, we investigate the role of StTGA2.1, a potato TGA lacking the full bZIP, which we name a mini-TGA. Such truncated proteins have been widely assigned as loss-of-function mutants. We, however, confirm that StTGA2.1 overexpression compensates for SA-deficiency. To understand the underlying mechanisms, we show that StTGA2.1 can physically interact with StTGA2.2 and StTGA2.3, while its interaction with DNA was not detected. We investigate the changes in transcriptional regulation due to StTGA2.1 overexpression, identifying direct and indirect target genes. Using in planta transactivation assays, we confirm that StTGA2.1 interacts with StTGA2.3 to activate StPRX07, a member of class III peroxidases, which are known to play role in immune response. Finally, via structural modelling and molecular dynamics simulations, we hypothesise that the compact molecular architecture of StTGA2.1 distorts DNA conformation upon heterodimer binding to enable transcriptional activation. This study demonstrates how protein truncation can lead to novel functions and that such events should be studied carefully in other protein families.

plant biology↗

bioRxiv2021

Day length-dependent thermal COP1 dynamics integrate conflicting seasonal cues in the control of Arabidopsis elongation

As the summer approaches, plants experience enhanced light inputs and elevated temperatures, two environmental cues with an opposite morphogenic impact. How plants integrate this conflicting information throughout seasons remains unclear. Key components of the plant response to light and temperature include phytochrome B (phyB), PHYTOCROME INTERACTING FACTOR 4 (PIF4), EARLY FLOWERING 3 (ELF3) and CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1). Here, we used hypocotyl lengths of single and double mutant/over-expression lines to fit a mathematical model incorporating known interactions of these genes. The fitted model recapitulates day length-dependent thermoelongation of all lines studied, and correctly predicts temperature responsiveness of new genotypes. Whilst previous works pointed to a lightindependent thermal function of COP1, simulations of our model suggested that COP1 has a role in temperature-signaling only during daytime. Based on by this prediction, we show that COP1 overexpression increases thermal response in continuous white light, while it has little effect in darkness. Defective thermal response of cop1-4 mutants is epistatic to phyB-9 and elf3-8, indicating that COP1 activity is essential to the transduction of phyB and ELF3 thermosensory function. Our model accurately captures phyB, ELF3 and PIF4 dynamics, providing an excellent toolbox for identification of best allelic combinations towards optimized crops resilience to climate change at different geographical latitudes.

plant biology↗

bioRxiv2021

Hysteresis in PIF4 and ELF3 dynamics dominates warm daytime memory in Arabidopsis

Plants may experience large diurnal temperature fluctuations. Our knowledge of the molecular mechanisms of integration of these fluctuations and the resulting growth patterns is limited. Here we show that hypocotyl growth during the night responded not only to the current temperature but also to preceding daytime temperatures, revealing a memory of previous conditions. Daytime temperature affected the nuclear levels of PHYTOCHROME INTERACTING FACTOR 4 (PIF4) and LONG HYPOCOTYL 5 (HY5) during the next night. These jointly accounted for the observed growth kinetics, whereas memory of prior daytime temperature was impaired in the pif4 and hy5 mutants. PIF4 promoter activity largely accounted for the temperature dependent changes in PIF4 protein levels. Noteworthy, the decrease in PIF4 promoter activity triggered by cooling required a stronger temperature shift than the increase caused by warming. This hysteretic pattern required EARLY-FLOWERING 3 (ELF3). Warm temperatures promoted the formation of nuclear condensates of ELF3 in hypocotyl cells during the afternoon but not in the morning. These nuclear speckles showed poor sensitivity to subsequent cooling. We conclude that ELF3 achieves hysteresis and drives the PIF4 promoter into the same behaviour, enabling a memory of daytime temperature conditions.

plant biology↗

bioRxiv2021

A quantitative gibberellin signalling biosensor reveals a role for gibberellins in internode specification at the shoot apical meristem

Growth at the shoot apical meristem (SAM) is essential for shoot architecture construction. The phytohormones gibberellins (GA) play a pivotal role in coordinating plant growth, but their role in the SAM remains mostly unknown. Here, we developed a ratiometric GA signalling biosensor by engineering one of the DELLA proteins, to suppress its master regulatory function in GA transcriptional responses while preserving its degradation upon GA sensing. We demonstrate that this novel degradation-based biosensor accurately reports on cellular changes in GA levels and perception during development. We used this biosensor to map GA signalling activity in the SAM. We show that high GA signalling is found primarily in cells located between organ primordia that are the precursors of internodes. By gain- and loss-of-function approaches, we further demonstrate that GAs regulate cell division plane orientation to establish the typical cellular organisation of internodes, thus contributing to internode specification in the SAM.

plant biology↗

bioRxiv2020

Precise transcriptional control of cellular quiescence by BRAVO/WOX5 complex in Arabidopsis roots

Root growth and development are essential features for plant survival and the preservation of terrestrial ecosystems. In the Arabidopsis primary root apex, stem-cell specific transcription factors BRAVO and WOX5 co-localize at the Quiescent Center (QC) cells, where they repress cell division so that these cells can act as a reservoir to replenish surrounding stem cells, yet their molecular connection remains unknown. Here, by using empirical evidence and mathematical modeling, we establish the precise regulatory and molecular interactions between BRAVO and WOX5. We found that BRAVO and WOX5 regulate each other besides forming a transcription factor complex in the QC necessary to preserve overall root growth and architecture. Our results unveil the importance of transcriptional regulatory circuits at the quiescent and stem cells to the control of organ initiation and growth of plant tissues.

plant biology↗

bioRxiv2019

The origin of the Gravettians: genomic evidence from a 36,000-year-old Eastern European

The Gravettian technocomplex was present in Europe from more than 30,000 years ago until the Last Glacial Maximum, but the source of this industry and the people who manufactured it remain unsettled. We use genome-wide analysis of a ~36,000-year-old Eastern European individual (BuranKaya3A) from Buran-Kaya III in Crimea, the earliest documented occurrence of the Gravettian, to investigate relationships between population structures of Upper Palaeolithic Europe and the origin and spread of the culture. We show BuranKaya3A to be genetically close to both contemporary occupants of the Eastern European plain and the producers of the classical Gravettian of Central Europe 6,000 years later. These results support an Eastern European origin of an Early Gravettian industry practiced by members of a distinct population, who contributed ancestry to individuals from much later Gravettian sites to the west.

genetics↗

bioRxiv2018

Pattern of severe injuries in Spanish children: boys and falls are alarmingly overrepresented

Background: Taking into account that injury is one of the main causes of child fatalities in developed countries, and that boys are more likely to suffer it than girls, we have explored a database of pediatric patients with severe injuries to determine whether sex and age influence the pattern of these fatalities, and the magnitude of this.\n\nMethod: Observational study of the demographic and clinical characteristics of 227 patients from a Spanish pediatric reference hospital, all of them admitted with a diagnosis of trauma.\n\nResult: Falls are the most frequent type of trauma (60.7%), followed by pedestrian traffic collisions (15%). Boys are over-represented in falls (72% vs 28% in girls) and pedestrian traffic injuries (61% vs 39 %). In boys, falls are mainly observed in public roads and during leisure activities (53.8%) whereas in girls at home (55.2%). In a logistic regression, sex and age are statistically significant predictors of severe trauma, boys (OR = 1.59) and the adolescent age group (OR = 3.7) showed the highest odds.\n\nConclusion: We have observed a clear gender-biased pattern of injury-related events: falls are the leading cause of injuries, with 2.5 boys for every girl. Falls mostly happened during outdoor leisure activities in boys and at home in girls. Pedestrian traffic injuries also show significant differences between sexes, emphasizing the role of cognitive and cultural factors in childrens behavior.

epidemiology↗

bioRxiv2018

Soil salinity inhibits plant shade avoidance

Global food production is set to keep increasing despite a predicted decrease in total arable land [1]. To achieve higher production, denser planting will be required on increasingly degraded soils. When grown in dense stands, crops elongate and raise their leaves in an effort to reach sunlight, a process termed shade-avoidance [2]. Shade is perceived by a reduction in the ratio of red (R) to (FR) light and results in the stabilisation of a class of transcription factors known as PHYTOCHROME INTERACTING FACTORs (PIFs) [3,4]. PIFs activate the expression of auxin biosynthesis genes [4,5] and enhance auxin sensitivity [6], which promotes cell wall loosening and drives elongation growth. Despite our molecular understanding of shade-induced growth, little is known about how this developmental programme is integrated with other environmental factors.\n\nHere we demonstrate that low levels of NaCl in soil strongly impair the ability of plants to respond to shade. This block is dependent upon abscisic acid (ABA) signalling and the canonical ABA signalling pathway. Low R:FR light enhances the expression of a positive regulator of the brassinosteroid (BR) signalling pathway, BRASSINOSTEROID SIGNALLING KINASE 5 (BSK5). We found that ABA inhibits BSK5 up-regulation and interferes with GSK3-like kinase inactivation by the BR pathway, thus leading to a suppression of PIF function. By demonstrating a link between the ABA and BR-signalling pathways this study provides an important step forward in our understanding of how environmental cues are integrated into plant development.

plant biology↗