Biology subjects

Campli, G.

Publications and source records attributed to Campli, G..

7 recordsLinked to original sources

bioRxiv2026

An evolvable and functionally partitioned network underlies developmental remodelling in teleosts

Comparative embryology has revealed that early animal development is based on highly conserved genetic programs. Beyond embryogenesis however, animals undergo remarkably diverse post-embryonic developmental transitions such as metamorphosis. Whether these transitions are also organised into conserved genetic programs remains largely unexplored. To identify conserved genetic programs underlying post-embryonic development, we examine metamorphic remodelling in five teleost fishes, spanning 200 million years of evolution. By integrating comparative co-expression networks, evolutionary genomics, phylogenetic modelling, and functional data in zebrafish, we uncovered a conserved post-embryonic developmental network. This conserved network comprises components involved in core cellular processes, and involved in development and physiology, both of which are under the control of thyroid hormone during metamorphosis. Despite evolutionary conservation at the coding sequence level, this network exhibits significant turnover in gene family copy number following the teleost-specific whole-genome duplication as well as lineage-specific expansions and contractions. The variation in gene copy numbers is associated with macroevolutionary variation in a number of ecological and morphological traits, including swimming performance, and trophic level. Cross-species tissue expression, zebrafish single-cell transcriptomics, and zebrafish perturbation phenotypes placed the implicated genes in biological contexts relevant to these traits. Together, our results provide evidence of an ancient, functionally partitioned post-embryonic developmental network that has diversified throughout teleost evolution. The heterochronic variation in network function, changes in endocrine activity, and gene-family turnover provide potential routes through which a shared developmental architecture contributed to the evolution of phenotypic diversity in teleosts.

evolutionary biology↗

bioRxiv2026

Gene family evolutionary dynamics reveal convergent genomic signatures in pancrustacean metamorphosis

Arthropod developmental modes are highly diverse, ranging from direct development with little morphological change between moults to metamorphic life-stage progressions characterised by profound transformations. Metamorphosis can be defined as a post-embryonic life-stage progression event leading to adulthood that is characterised by major morphological changes and modifications of the adaptive landscape. Within this framework, we compare four independent evolutionary life history transitions to metamorphic development across Pancrustacea. Using a phylogenomic dataset of 54 species spanning 26 orders, we investigated gene family evolutionary dynamics associated with the inferred origins of metamorphosis in Insecta, Copepoda, Eucarida, and Thecostraca. Compared with non-metamorphic sister lineages as well as descendent and ancestral nodes, transitions to metamorphic development were consistently associated with elevated gene family births and expansions. Although these expansions predominantly involved different gene families in each lineage, they repeatedly converged on shared biological functions, particularly those related to embryonic and post-embryonic development, morphogenesis, nervous system differentiation, and other processes relevant to the biology and evolution of metamorphosis. Evolutionary modelling further identified a subset of gene families exhibiting adaptive, lineage-specific expansions, including genes implicated in neural and sensory development, segmentation, and moulting. Together, these findings support a model in which independent transitions to metamorphic development repeatedly recruited different components of a shared developmental toolkit, achieving functional convergence through distinct genetic trajectories. This reframes the arthropod moulting programme as an evolutionarily flexible developmental substrate whose repeated modification has facilitated the emergence of complex multi-phasic life histories and contributed to the extraordinary diversification of Pancrustacea.

evolutionary biology↗

bioRxiv2026

Moulting in Pancrustacea is characterised by both deeplyconserved and recently evolved gene modules

Arthropods such as insects and crustaceans, which together form the monophyletic group Pancrustacea, possess a rigid chitinous exoskeleton that must be periodically shed through moulting to allow growth and morphological change. Although moulting is a deeply conserved developmental process across Arthropoda, our understanding of its molecular mechanisms is still largely derived from insect model species. Lineage-specific innovations and losses of moulting related genes raise fundamental questions on the extent of its conservation outside non-insect arthropods. Here, we investigate the evolutionary conservation of moulting gene expression across five representative pancrustacean species using publicly available transcriptomic datasets. Changes in gene expression during moulting are characterized by both deeply conserved and lineage-specific gene modules. Temporal gene expression analyses reveal that these lineage-specific signatures are not uniformly distributed across the moulting process: the middle transitional phase is more lineage-specific, thereby exhibiting an inverse hourglass pattern. This is likely due to life-history specific processes, development of the cuticle and specialized structures of the exoskeleton. Overall, this study provides evidence for both the evolutionary conservation and divergence of this key post-embryonic developmental process and highlights the modular architecture of the moulting programme.

evolutionary biology↗

bioRxiv2025

Evolutionary dynamics of the arthropod moulting machinery

Exoskeletons define arthropods, providing support for segmented bodies and appendages while protecting against environmental stress and predation. Although ubiquitous, this evolutionarily variable feature has enabled arthropods to occupy diverse lifestyles and ecological niches, contributing to their unrivalled diversity. Because the chitinous cuticle is rigid, exoskeletons must be periodically shed and replaced as animals grow. Arthropods therefore develop through discrete moults, with conserved phases that progress from pre-moult preparation to ecdysis and post-moult maturation. These are tightly regulated developmental transitions controlled by a molecular toolkit comprising neuropeptides, hormone-synthesising enzymes, receptors, and the early, fate, and late gene sets that activate and execute the moulting process. Although genetic studies in model species have identified many components, major knowledge gaps remain, especially in non-insect arthropods. Advances in genome sequencing now enable comparative genomic analyses across diverse, previously understudied arthropod lineages to begin to address these gaps. We present a comprehensive comparative genomic survey of arthropods, sampling all four subphyla: Chelicerata, Myriapoda, Crustacea, and Hexapoda. Orthology inference and gene copy-number analyses contrast stable and dynamic components of the moulting machinery across the phylum. Ancestral state reconstructions and phylogenetic reconciliations reveal gene duplication and loss dynamics and the evolutionary histories of key moulting gene families. The inclusion of newly generated myriapod genomes addresses a major taxonomic gap and enables inferences of gene repertoire changes in the Mandibulata ancestor. The broad taxonomic representation enables a phylum-wide assessment to systematically evaluate, refine, and revise current understanding of the evolutionary dynamics of the entire moulting genetic toolkit.

evolutionary biology↗

bioRxiv2025

Comparative chemosensory mechanisms underlying larval foraging and competitive advantage in Aedes albopictus and Aedes aegypti

The invasive Asian tiger mosquito, Aedes albopictus (Skuse), and yellow fever mosquito, Aedes aegypti (L.) are known to compete for resources during the larval stage, often resulting in the ecological displacement of Ae. aegypti by Ae. albopictus. The chemosensory system plays a pivotal role in larval foraging behavior and may contribute to the competitive advantage. Here, we employed comparative transcriptomics and functional characterization of odorant receptors (ORs) to investigate species-specific differences in larval olfaction. Notably, we uncovered functional variation within the conserved olfactory indole receptor clade, indicating distinct ecological adaptations across species and life stages. We also developed a novel approach to functionally characterize the larval sensory cone and mapped its receptor neuron projections to two key brain regions: the antennal lobe and the subesophageal ganglion. This study provides new insights into the molecular and neural basis of chemosensory-driven behavior in mosquito larvae and highlights the potential role of olfaction in shaping interspecies competition and ecological success.

neuroscience↗

bioRxiv2024

Evolution of venom production in marine predatory snails

Venom-secreting glands are highly specialised organs evolved throughout the entire animal kingdom to synthetise and secrete toxins for predation and defence. Venom is extensively studied for its toxin components and application potential; yet, how animals become venomous remains poorly understood. Venom systems therefore offer a unique opportunity to understand the molecular mechanisms underlying functional innovation. Here, we conducted a multi-species multi-tissue comparative transcriptomics analysis of 12 marine predatory gastropods, including species with venom glands and species with homologous non-venom producing glands, to examine how specialised functions evolve through gene expression changes. We found that while the venom gland specialised for the mass production of toxins, its homologous glands retained the ancestral digestive functions. The functional divergence and specialisation of the venom gland was achieved through a redistribution of its ancestral digestive functions to other organs, specifically the oesophagus. This entailed concerted expression changes and accelerated transcriptome evolution across the entire digestive system. The increase in venom gland secretory capacity was achieved through the modulation of an ancient secretory machinery, particularly genes involved in endoplasmic reticulum stress and unfolded protein response. This study shifts the focus from the well-explored evolution of toxins to the lesser-known evolution of the organ and mechanisms responsible for venom production. As such, it contributes to elucidating the molecular mechanisms underlying organ evolution at a fine evolutionary scale, highlighting the specific events that lead to functional divergence.

evolutionary biology↗

bioRxiv2022

Taxonbridge: an R package to create custom taxonomies based on the NCBI and GBIF taxonomies

SummaryBiological taxonomies establish conventions by which researchers can catalogue and systematically compare their work using nomenclature such as species binomial names and reference identifiers. The ideal taxonomy is unambiguous and exhaustive; however, no such single taxonomy exists, partly due to continuous changes and contributions made to existing taxonomies. The degree to which a taxonomy is useful furthermore depends on context provided by such variables as the taxonomic neighbourhood of a species (e.g., selecting arthropod or vertebrate species) or the geological time frame of the study (e.g., selecting extinct versus extant species). Collating the most relevant taxonomic information from multiple taxonomies is hampered by arbitrarily defined identifiers, ambiguity in scientific names, as well as duplicated and erroneous entries. The goal of taxonbridge is to provide tools for merging the Global Biodiversity Information Facility (GBIF) Backbone Taxonomy and the United States National Center for Biotechnology Information (NCBI) Taxonomy in order to create consistent, deduplicated and disambiguated custom taxonomies that reference both extant and extinct species. AvailabilityTaxonbridge is available as a package in the Comprehensive R Archive Network (CRAN) repository: https://CRAN.R-project.org/package=taxonbridge. Contactwernerpieter.veldsman@unil.ch

bioinformatics↗