Biology subjects

Brejon Lamartiniere, E.

Publications and source records attributed to Brejon Lamartiniere, E..

3 recordsLinked to original sources

bioRxiv2025

Predicting porcini: a decade of sporocarp monitoring reveals the meteorological triggers of Boletus edulis fruiting in central European beech forests

Despite recent molecular and genomic advances, the reproductive biology of ectomycorrhizal fungi (EMF) remains poorly understood. In particular, the meteorological cues triggering sporocarp formation remain largely unknown, limiting our ability to induce fruiting in the laboratory. To address this knowledge gap, we analysed a decade-long (2015-2024) dataset of daily, near-exhaustive sporocarp observations from an intensively monitored population of Boletus edulis in a central European beech forest near Bielefeld, Germany. Using generalised linear mixed-effect models, we estimated the lagged effects of temperature and precipitation on sporocarp formation and identified the conditions associated with peak fruiting. Although sporocarps formed across a broad range of conditions, peak fruiting was associated with a mean temperature of approximately 13{degrees}C averaged over the preceding 20 days and increased linearly with precipitation accumulated over a 26-day window. Under projected warmer and drier autumn conditions, B. edulis sporocarp formation in European beech forests is likely to decline.

ecology↗

bioRxiv2024

A haplotype-resolved chromosomal reference genome for the porcini mushroom Boletus edulis

Haplotype-resolved chromosomal reference genomes are increasingly available for many fungi, offering insights into the evolution of pathogenic and symbiotic lifestyles. However, these resources remain scarce for ectomycorrhizal fungi (EMF), which play crucial roles in forest ecosystems. Here, we used a combination of chromatin conformation capture (Hi-C) and PacBio sequencing to construct a haplotype-resolved chromosomal genome assembly for Boletus edulis, an emerging model for EMF research and a prized edible fungus. Our new reference assembly, "BolEdBiel_h2", derives from a sporocarp sampled in Bielefeld, Germany. The genome assembly spans 41.8 Mb, with a scaffold N50 of 4.1 Mb, and includes 11 chromosome-level scaffolds, achieving near telomere-to-telomere coverage across multiple chromosomes. We annotated 15,406 genes, with a Benchmarking Universal Single-Copy Orthologs (BUSCO) score of 96.2%. Key genomic features such as mating loci, CAZymes, and effector proteins, were mapped across the assembly. As a first application of this new genomic resource, we mapped whole genome resequencing data from 49 genets to investigate the population structure and genetic diversity of the European lineage of B. edulis. We identified five distinct genetic clusters and found that high-latitude populations from Iceland and Fennoscandia exhibited greater nucleotide diversity than populations from the United Kingdom and central Europe. Additionally, we discovered a 0.4 Mb inversion on chromosome three and identified several regions of locally elevated nucleotide diversity, which may represent candidates for ecological adaptation. This genomic resource will facilitate a deeper understanding of this ecologically and commercially important wild fungus.

evolutionary biology↗

bioRxiv2023

From populations to pan-genomes: investigating the role of ecology and genomic architecture in maintaining species boundaries in the porcini mushroom, Boletus edulis

Hybridization among diverged species is common across all domains of eukaryotic life, but appears to be particularly common in fungi. However, some fungi exhibit a greater tendency for hybridization than others and it is unclear what mechanisms facilitate or prevent hybridization. Here, we generated 253 whole genome sequences and 22 reference genomes within the globally distributed ectomycorrhizal species complex Boletus edulis Bull. and use a multi-faceted genomic approach to identify patterns of ongoing hybridization and determine whether hybridization is mediated by changes in genome structure, ecology, or both. We found that hybridization is common among species of B. edulis despite 2.1 million years of divergence. However, not all lineages that hybridize today exhibit patterns of introgression, indicating the presence of strong reproductive boundaries among some species. Using a pan-genomic approach we find that genome structural variation is abundant within B. edulis, but that the presence of ongoing introgression does not correlate with genome structural similarity or overall gene content. Instead, we find that the composition of ecologically relevant gene families more accurately predicts the presence of introgression among lineages and B. edulis as a group may specialize on chitin decomposition. Altogether, we show that ecological preferences are likely the primary driver of reproductive barriers in B. edulis.

evolutionary biology↗