Biology subjects

Robin, A.

Publications and source records attributed to Robin, A..

5 recordsLinked to original sources

bioRxiv2026

Contrasting biotic and abiotic drivers of Glomeromycotina and Mucoromycotina mycorrhizal associations in a durum wheat field

Mucoromycotina fine root endophyte (M-FRE), although commonly present in cultivated crops, represent a largely overlooked symbiosis, and their diversity and ecological functions under natural field conditions remain poorly understood. The co-occurrence of M-FRE and Glomeromycotina arbuscular mycorrhizal fungi (G-AMF) was assessed in field-grown durum wheat (Triticum turgidum subsp. durum (Desf.) Husn.), testing the effects of combined water and nitrogen limitation on root colonization and fungal community diversity in roots, rhizosphere, and extra-radical hyphae. The M-FRE colonization was reduced under combined water and nitrogen stress but was unaffected by wheat genotype. In contrast, G-AMF colonization varied among genotypes and was insensitive to this combined stress. While G-AMF colonization correlated with root traits, M-FRE abundance was rather determined by soil properties and the applied stress. Remarkably, under stress, M-FRE but not G-AMF colonization correlated with nitrogen and phosphorus uptake in plant shoots. Partial 18S metabarcoding detected 74 G-AMF taxa and 12 M-FRE taxa, some shared across compartments, revealing active growth of M-FRE extra-radical hyphae. Stress had contrasting effects on diversity: G-AMF alpha diversity remained stable, whereas M-FRE diversity declined, with stress driving distinct community structures for both groups. These results indicate that M-FRE and G-AMF are shaped by divergent drivers, highlighting functional differences between these morphologically similar symbioses.

ecology↗

bioRxiv2025

Draft genome of Trichoderma gamsii strain T035 a promising beneficial fungus in agriculture

AO_SCPLOWBSTRACTC_SCPLOWTrichoderma gamsii is a filamentous fungus widely recognized for its beneficial roles in agriculture, particularly for its ability to suppress plant pathogens and enhance crop health. However, genomic resources for this species remain scarce, limiting functional and applied studies. Here, we report the high-quality genome of T. gamsii strain T035, a promising biocontrol strain with significant antagonistic activity against several pathogens in vitro. The assembly consisted of 16 sequences, including near 7 chromosome-scale sequences, with an N50 value of 7.2 Mbp and a total assembly length of 38.8 Mbp. This genome represents the most complete T. gamsii assembly to date and will provide a valuable resource to facilitate the exploration of molecular mechanisms underlying biocontrol and support the development of sustainable plant protection strategies.

genomics↗

bioRxiv2025

Reading about sensations recruits the posterior insula: An intracranial EEG study

When we read, how do words and sentences become concepts? Contrary to theoretical perspectives that conceptualize meaning and concepts as symbolic and abstract, embodied approaches propose that semantic access relies on mental simulations of bodily experiences□associated with the word’s meaning (e.g., simulating the act of running when we read the word ‘run’ or feeling pain when reading the word ‘burn’). If this view of cognition underpins conceptual processing, then sensory and motor cortices should play an early role during language comprehension. To test this idea, we recorded intracranial neural activity (High-Frequency Activity, 50–150 Hz) in epileptic patients while they read short sentences from different semantic categories: abstract-, action- and sensation-related. We hypothesized that reading sensation-related sentences (e.g., “he burns me”) would preferentially involve the posterior insula — a key region for processing affective and painful sensations. Our results, revealed an early functional dissociation between the anterior and posterior insula: the anterior insula showed a non-selective response across all semantic categories, whereas the posterior insula presented an early selective response (around 170 ms) for the sensation-related ones. Furthermore, the intensity of this selective neural response in the posterior insula correlated with the intensity of subjective perceived pain. These results provide direct intracranial evidence suggesting that language is deeply rooted in body-environment interactions.

neuroscience↗

bioRxiv2024

A functional overlap between evidence accumulation, confidence, and changes of mind in the pre-supplementary motor area and insula

Evidence accumulation models have proven to be powerful tools to explain the temporal dynamics of decisions, as well as their metacognitive components such as confidence judgments and changes of mind. However, it is still unclear how and where in the brain evidence accumulation leads to these two metacognitive components. To better understand the functional overlap between evidence accumulation, confidence, and changes of mind, we recorded intracranial high-gamma activity in patients with focal epilepsy while they reported the motion direction of a random dot kinetogram with a computer mouse, and estimated their confidence level. We found an anatomical overlap between the neural correlates of evidence accumulation, confidence, and changes of mind in the pre-supplementary motor area, as well as in the orbitofrontal, inferior frontal, and insular cortices. Both mouse-tracking behaviour and electrophysiological results were reproduced with a post-decisional evidence accumulation model. After characterising the temporal dynamics of decision-making with mouse-tracking and intracranial electrophysiology, we conclude that confidence and changes of mind result from evidence accumulation instantiated before the decision in the pre-supplementary motor area, and after the decision in the insula.

neuroscience↗

bioRxiv2024

Cortical evidence accumulation for perceptual experience occurs irrespective of reports

Perceptual experience is a multi-faceted, dynamical process, tackled empirically through measures of stimulus detectability and confidence. To assess if stimulus detection and confidence can be explained by evidence accumulation, a form of sequential sampling of sensory evidence, we analyzed high-gamma activity from stereo-electroencephalographic data of 29 participants partaking in 3 pre-registered experiments. In an immediate-response experiment, individual channels and decoded multivariate latent variables in the visual, inferior frontal, and anterior insular cortices displayed functional markers of evidence accumulation. In two further experiments, this signal in the ventral visual cortex differentiated between (1) seen and unseen stimuli in delayed detection, (2) high and low intensity stimuli during passive viewing, and (3) levels of confidence when stimuli were seen. A computational model of leaky evidence accumulation successfully reproduced both behavioral and neural data. Overall, these results indicate that evidence accumulation explains key aspects of perceptual experience, encompassing both conscious access and monitoring.

neuroscience↗