Biology subjects

Minambres, E.

Publications and source records attributed to Minambres, E..

3 recordsLinked to original sources

bioRxiv2026

Fungal volatiles affect lateral root formation and increase plant tolerance to osmotic stress

Symbiotic fungi communicate with plants via volatile organic compounds (VOCs), even before physical contact. While fungal VOCs are known to promote plant development under control conditions, their effects under abiotic stress remain poorly characterized. Here, we exposed Arabidopsis thaliana seedlings to VOCs from the ectomycorrhizal fungi Laccaria bicolor and Hebeloma cylindrosporum, and the endophyte Serendipita indica, under osmotic stress. Time-course transcriptional analysis revealed a rapid, transient induction of auxin transport genes within 3 days of VOC exposure, with minimal early cytokinin modulation. Using auxin- (aux1-7, axr1-3) and cytokinin-resistant (cre1, arr1-4) mutants, we show that this early response bypasses classic auxin/cytokinin antagonism, promoting lateral root proliferation by day 10 under both control and stress conditions. Transcriptomic profiling indicated that fungal VOCs modulate glucosinolate and leucine metabolism and regulate potassium (HAK5) and iron (IRT1) transporters. Genetic and phenotypic analyses of hak5-2 and akt1-2 mutants, together with nitric oxide signaling components, revealed that potassium transport and nitric oxide-dependent IRT1 regulation are essential for translating VOC perception into developmental responses. These findings underscore the multifaceted mechanisms by which fungal VOCs coordinate plant development and abiotic stress tolerance.

plant biology↗

bioRxiv2025

Fungal VOCs regulate the expression of WOX5 at the root meristem of plants under osmotic stress in Arabidopsis and Populus tremuloides seedlings

Communication between plants and fungi occurs even before direct physical contact via various chemical signaling pathways, among them, volatile organic compounds (VOCs). Fungal VOCs, including those emitted by ectomycorrhizal and symbiotic endophytic fungi, significantly influence plant development and root architecture. However, the molecular signaling mechanisms underlying its regulation remain unknown. The quiescent center (QC), located within the primary root meristem, serves as a reservoir of stem cells that generate daughter cells and constituting a key regulatory site for architectural modulation. These daughter cells either divide or differentiate to form the transition zone, maintaining a crucial balance for root meristem homeostasis. WOX5, a homeobox transcription factor expressed predominantly in the QC, regulates surrounding stem cells by repressing their differentiation, thereby preserving the stem cell niche and is essential for root meristem integrity. In this study, we aimed to analyze the effects of fungal VOCs emitted by Laccaria bicolor, Hebeloma cylindrosporum, and Serendipita indica on the root architecture and meristem regulation in Arabidopsis thaliana and Populus tremuloides. Our results demonstrate the impact of these fungal VOCs on the root architecture of both species and underline the importance of WOX5 regulation mediated by fungal VOCs for maintaining root meristem homeostasis.

plant biology↗

bioRxiv2018

The telomeric Cdc13-Stn1-Ten1 complex regulates RNA polymerase II transcription

Specialized telomeric proteins have an essential role in maintaining genome stability through chromosome end protection and telomere length regulation. In the yeast Saccharomyces cerevisiae, the evolutionary conserved CST complex, composed of the Cdc13, Stn1 and Ten1 proteins, largely contributes to these functions. Here, we report the existence of genetic interactions between TEN1 and several genes coding for transcription regulators. Molecular assays confirmed this novel function of Ten1 and further established that it regulates the occupancies of RNA polymerase II and the Spt5 elongation factor within transcribed genes. Since Ten1, but also Cdc13 and Stn1, were found to physically associate with Spt5, we propose that Spt5 represents the target of CST in transcription regulation. Moreover, CST physically associates with Hmo1, previously shown to mediate the architecture of S phase-transcribed genes. The fact that, genome-wide, the promoters of genes down-regulated in the ten1-31 mutant are prefentially bound by Hmo1, leads us to propose a potential role for CST in synchronizing transcription with replication fork progression following head-on collisions.

molecular biology↗