Biology subjects

Barriere, P.

Publications and source records attributed to Barriere, P..

4 recordsLinked to original sources

bioRxiv2025

Genomic and morphometric evidence for Austronesian-mediated pig translocation in the Pacific

Human mediated translocation of non-native pig species (genus Sus) to the islands of Wallacea and Oceania has significantly altered local ecosystems. To investigate the timing and trajectory of these introductions, we conducted both genomic analyses of 576 pig nuclear genomes and a geometric morphometric analysis of 714 modern and ancient dental remains. Our analyses demonstrate that feral and domestic pigs in Wallacea and Oceania possess diverse ancestries resulting from the introduction of multiple, sequential pig populations followed by gene flow. Despite the variability in their genomic ancestry these pigs all possess a distinct tooth morphology, and a genetic link to the Chinese domestic pig populations that accompanied the dispersal of Austronesian language speakers [~]4,000-3,000 years ago via Taiwan and the Philippines.

evolutionary biology↗

bioRxiv2025

Affiliative behaviours regulate allostasis development and shape biobehavioural trajectories in horse

Social interactions shape both physiological and behavioural development of offspring and poor care/early caregiver loss are known to promote negative outcomes in adulthood in both animals and humans. How affiliative behaviours impact future development of offspring remains unknown. Here, we used Equus caballus (domestic horse) as a model to investigate this question. By coupling magnetic resonance imaging, longitudinal biobehavioural assessment and advanced multivariate statistical modelling we found that maternal presence during childhood promotes maturation of brain territories involved in both social behaviour (anterior cingulate, retrosplenial cortex) and physiological regulation (hypothalamus, amygdala). Additionally, we found that offsprings benefiting from prolonged maternal presence showed higher default mode network (DMN) connectivity, improved social competences, more efficient feeding behaviours, and metabolic profiles. The present study underscores the salient role of social interactions for the development of allostatic regulation in offspring.

neuroscience↗

bioRxiv2019

Spatio-temporal analysis of human preimplantation development reveals dynamics of epiblast and trophectoderm

Recent technological advances such as single-cell RNAseq1-3 and CRISPR-CAS9-mediated knock-out4 have allowed an unprecedented access into processes orchestrating human preimplantation development5. However, the sequence of events which occur during human preimplantation development are still unknown. In particular, timing of first human lineage specification, the process by which the morula cells acquire a specific fate, remains elusive. Here, we present a human preimplantation development model based on transcriptomic pseudotime modelling of scRNAseq biologically validated by spatial information and precise time-lapse staging. In contrast to mouse, we show that trophectoderm (TE) / inner cell mass (ICM) lineage specification in human is only detectable at the transcriptomic level at the blastocyst stage, just prior to expansion. We validated the expression profile of novel markers enabling precise staging of human preimplantation embryos, such as IFI16 which highlights establishment of epiblast (EPI) and NR2F2 which appears at the transition from specified to mature TE. Strikingly, mature TE cells arise from the polar side, just after specification, supporting a model of polar TE cells driving TE maturation. Altogether, our study unravels the first lineage specification event in the human embryo and provides a browsable resource for mapping spatio-temporal events underlying human lineage specification.

cell biology↗

bioRxiv2018

Development of a robust automated tool for the annotation of embryo morphokinetic parameters

Study QuestionIs it possible to automatically annotate human embryo development in time-lapse devices, with results comparable to manual annotation?\n\nSummary AnswerWe developed an automated tool for the annotation of embryo morphokinetic parameters having a high concordance with expert manual annotation in a large scale-study.\n\nWhat is Known AlreadyMorphokinetic parameters obtained with time-lapse devices are increasingly used for human embryo quality assessment. However, their annotation is timeconsuming and can be operator-dependent, highlighting the need of developing automated approaches.\n\nStudy Design, Size, DurationThis monocentric pilot study was conducted using 701 blastocysts originating from 584 couples undergoing IVF with embryo culture in a time-lapse device and on 4 mouse embryos.\n\nParticipants/Materials, Setting, MethodsAn automated annotation tool was developed based on grey level coefficient of variation and detection of the thickness of the zona pellucida. The timings of cellular events obtained with the automated tool were compared with those obtained manually by 2 expert embryologists. The same procedure was applied on 4 mouse preimplantation embryos obtained with a different device in a different setting.\n\nMain Results and the Role of ChanceAlthough some differences were found when embryos were considered individually, we found an overall excellent concordance between automated and manual annotation of human embryo morphokinetics from fertilization to expanded blastocyst stage (r2=0.94). Moreover, the automated annotation tool gave promising results across species (human, mice).\n\nLimitations, Reasons for CautionThese results should undergo multi-centric external evaluation in order to test the overall performance of the annotation tool.\n\nWider Implications of the FindingsOur system performs significantly better than the ones reported in the literature and on a bigger cohort, paving the way for high-throughput analysis of multicentric morphokinetic databases, providing new insights into the clinical value of morphokinetics as predictor of embryo quality and implantation.\n\nStudy Funding/Competing Interest(s)This study was partly funded by Finox Forward Grant 2016.\n\nTrial Registration NumberNA

developmental biology↗