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Beukeboom, L. W.

Publications and source records attributed to Beukeboom, L. W..

3 recordsLinked to original sources

Wolbachia: The architect of microbial assemblies in response to environmental changes

Translocating organisms from their habitats to laboratories, a method common in microbial ecology and evolution experiments, alters their microbial communities. However, the impact of translocation on microbiomes is often overlooked, limiting our ability to assess how laboratory findings relate to field dynamics. Its also crucial to examine organism responses with symbionts, as they can stabilise communities or increase vulnerability to changes. This study investigates the effects of laboratory introduction on host-microbiome interactions in the parasitic wasp Asobara japonica and its endosymbiont Wolbachia. Results indicate that transferring Wolbachia-infected (asexual) and uninfected (sexual) wasps to a laboratory decreased A. japonicas bacterial diversity. Stochastic processes drive community changes, with distinct alterations in bacterial composition between reproductive modes. Over four generations, asexual wasps bacterial communities became more uniform, while sexual wasps showed greater diversity. Notably, bacterial changes appeared across generations rather than immediately. Additionally, Wolbachia abundance changed following laboratory introduction, affecting community structure and assembly. In conclusion, our research demonstrates how laboratory conditions affect host-associated microbial communities depending on symbiont presence. This, in turn, can affect their functions, host interactions, and overall community dynamics. Thus, our findings stress the importance of linking lab results to real-world implications, posing a broader challenge for researchers.

microbiology↗

Divergent evolution of genetic sex determination mechanisms along environmental gradients

Sex determination (SD) is a crucial developmental process, but its molecular underpinnings are very diverse, both between and within species. SD mechanisms have traditionally been categorized as either genetic (GSD) or environmental (ESD), depending on the type of cue that triggers sexual differentiation. However, mixed systems, with both genetic and environmental components, are more prevalent than previously thought. Here, we show theoretically that environmental effects on expression levels of genes within SD regulatory mechanisms can easily trigger within-species evolutionary divergence of SD mechanisms. This may lead to the stable coexistence of multiple SD mechanisms and to spatial variation in the occurrence of different SD mechanisms along environmental gradients. We applied the model to the SD system of the housefly, a global species with world-wide latitudinal clines in the frequencies of different SD systems, and found that it correctly predicted these clines if specific genes in the housefly SD system were assumed to have temperature-dependent expression levels. We conclude that environmental sensitivity of gene regulatory networks may play an important role in diversification of SD mechanisms.

evolutionary biology↗

A single QTL with large effect is associated with female functional virginity in an asexual parasitoid wasp

During the transition from sexual to asexual reproduction, a suite of reproduction-related sexual traits become superfluous, and may be selected against if costly. Female functional virginity refers to asexual females resisting to mate or not fertilizing eggs after mating. These traits appear to be among the first that evolve during the gradual transition from sexual to asexual reproduction. The genetic basis of female functional virginity remains elusive. Previously, we reported that female functional virginity segregates as a single recessive locus in the asexual parasitoid wasp Asobara japonica. Here, we investigate the genetic basis of this trait by quantitative trait loci (QTL) mapping and candidate gene analyses. Consistent with the segregation of phenotypes, a single QTL of large effect was found spanning over 4.23 Mb and comprising at least 131 protein-coding genes, of which 15 featured sex-biased expression in the related sexual Asobara tabida. We speculate that two of these 15 genes may be of particular interest: CD151 antigen and nuclear pore complex protein Nup50. Overall, our results are consistent with a single gene or a cluster of linked genes underlying rapid evolution of female functional virginity in the transition to asexuality. Once a mutation for rejection to mate has swept through a population, the region comprising the gene(s) does not get smaller due to lack of recombination in asexuals.

evolutionary biology↗