Biology subjects

Ke, Y.-H.

Publications and source records attributed to Ke, Y.-H..

4 recordsLinked to original sources

bioRxiv2026

Not all roads lead to selfing: mating-system stability in an invasive ectomycorrhizal fungus

Baker's rule predicts that selfing is a beneficial trait for colonizers, whose prediction in the kingdom Fungi is reinforced by recent work showing the invasive ectomycorrhizal basidiomycete Amanita phalloides with self-incompatibility (SI) system has evolved unisexual reproduction in its introduced range. Unlike in plants, the multiallelic SI system of basidiomycetes does not fully prevent selfing among the meiotic offspring of a single dikaryotic (diploid) parent. This distinction allows observation of an intermediate state of selection where selfing is preferred in a species with SI system during colonization before a change in self-incompatibility architecture. Here, we analyzed the genomes of 189 isolates of the ectomycorrhizal basidiomycete Suillus luteus collected from both its native European range and five independently introduced regions to test whether selfing rates increase and whether the SI system had degraded after introduction. Unlike the A. phalloides case, we found no evidence of unisexual reproduction or loss of the SI system in the introduced ranges of S. luteus. Rather, all introduced populations maintained outcrossing rates higher than random mating as in the native populations. However, selfing events were detected in three individuals from a single introduced population, representing the first documented case of selfed sporocarps of Boletales fungi. Our works in S. luteus demonstrates that although selfing is possible in this species, it is not favored during colonization, potentially due to inbreeding depression and higher population density, highlighting the complex interaction among the invasion biology, genetics, and the colonizing context.

evolutionary biology↗

bioRxiv2026

Global population structures and demographic history of Suillus luteus, a pine co-introduced ectomycorrhizal fungus associated with exotic forestry and invasion.

Human colonization since the 19th century has resulted in the global spread of pines across the Southern Hemisphere, well beyond their original northern boreal distribution. Such introductions moved not only the pines but also expanded the distribution of their symbiotic partners. Although the introduction of pines is documented through historical records, little is known about the introduction history of their ectomycorrhizal fungi, which are critical symbionts for the survival and invasion of pines. Using Suillus luteus as an example, population genomic analyses of 208 individuals across both native and introduced ranges showed that all introductions originated from Europe, likely mediated by human activities along with pine introductions. With the exception of North America, introduced populations were genetically differentiated from the Europe population, with varying magnitudes of population expansion in different introduced regions, often linked to forestry practices. Genetic variation within the native European population followed isolation by distance, but not in the introduced range, highlighting the disparity in the spatial genetic patterns of native versus exotic habitats. This study provides insight into the population genetics of a globally introduced ectomycorrhizal fungus whose introduction process is likely applicable to other pine-co-introduced ectomycorrhizal fungi.

evolutionary biology↗

bioRxiv2024

Biosynthetic Gene Cluster Diversity Across Native and Introduced Populations of an Ectomycorrhizal Fungus, Suillus luteus

Non-pathogenic fungi are being increasingly recognized for their involvement in biological invasions, where they have the potential to cause ecological and economical harm. One notable example is the ectomycorrhizal (EcM) fungus, Suillus luteus, which is commonly found co-invading with non-native pines that have escaped from commercial pine plantations across the Southern Hemisphere. In such invasions, selection pressures imposed by novel plants, soil microbes, and environmental conditions, as well as impoverished assemblages of co-invading EcM fungi, may exert particularly strong selective effects and contribute to driving evolutionary divergence in traits. We investigated the potential impact of this global co-introduction on biosynthetic gene cluster (BGC) diversity in native and introduced populations of S. luteus. We found that native populations demonstrated higher BGC diversity at both the gene and clan levels compared to introduced populations. Additionally, we identified a collection of unique BGCs as well as 24 highly conserved clans, including two featuring known pathways, within both native and introduced populations. Furthermore, our study confirmed the presence of three previously identified clades of S. luteus with distinct gene cluster family (GCF) diversity. Thus, our study concludes that the introduction of S. luteus has driven evolutionary changes in its BGCs, underscoring the broader implications of global co-introductions on fungal adaptation in new environments.

evolutionary biology↗

bioRxiv2019

Incipient local adaptation in a fungus: evolution of heavy metal tolerance through allelic and copy-number variation

Human-altered environments can shape the evolution of organisms. Fungi are no exception, though little is known about how they withstand anthropogenic pollution. Here, we document incipient polygenic local adaptation in the mycorrhizal fungus Suillus luteus driven by recent soil heavy metal contamination. Genome scans across individuals from recently polluted and nearby unpolluted soils in Belgium revealed no evidence of population structure but detected allelic divergence and gene copy number variation in genes involved in metal exclusion, storage, immobilization, and reactive oxygen species detoxification. Standing genetic variation included multiple alleles of small effects contributing to heavy metal tolerance, suggesting the existence of different strategies to withstand contamination. These variants were shared across the whole population but under selection in isolates exposed to pollution. Together, our results point to S. luteus undergoing the initial steps of adaptive divergence and contribute to understanding the processes underlying local adaptation under strong environmental selection.

evolutionary biology↗