I graduated from Sorbonne University (France) in Molecular and Cellular Biology, and I started my PhD at the Villefranche-sur-Mer marine station, where my research focused on the develoment and evolution of the nervous system in sea urchins, and on the roles of intercellular signaling pathways in this process. As part of my PhD, I spent one year at the Shimoda Marine Research Center (Japan). I am now trying to understand how morphological diversity emerged from gene regulatory networks, using echinoderms and other cool animals like accorn worms. I am broadly fascinated by developmental biology, evolution, and zoological studies of weird animals in general.
Christopher Lowe, Postdoctoral Faculty Sponsor
Integrating Complex Life Cycles in Comparative Developmental Biology.
Annual review of genetics
The goal of comparative developmental biology is identifying mechanistic differences in embryonic development between different taxa and how these evolutionary changes have led to morphological and organizational differences in adult body plans. Much of this work has focused on direct-developing species in which the adult forms straight from the embryo and embryonic modifications have direct effects on the adult. However, most animal lineages are defined by indirect development, in which the embryo gives rise to a larval body plan and the adult forms by transformation of the larva. Historically, much of our understanding of complex life cycles is viewed through the lenses of ecology and zoology. In this review, we discuss the importance of establishing developmental rather than morphological or ecological criteria for defining developmental mode and explicitly considering the evolutionary implications of incorporating complex life cycles into broad developmental comparisons of embryos across metazoans. Expected final online publication date for the Annual Review of Genetics, Volume 57 is November 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
View details for DOI 10.1146/annurev-genet-071719-020641
View details for PubMedID 37585618
Neural anatomy of echinoid early juveniles and comparison of nervous system organization in echinoderms.
The Journal of comparative neurology
The echinoderms are a phylum of marine deuterostomes characterized by the pentaradial (five fold) symmetry of their adult bodies. Due to this unusual body plan, adult echinoderms have long been excluded from comparative analyses aimed at understanding the origin and evolution of deuterostome nervous systems. Here, we investigated the neural anatomy of early juveniles of members of three of the five echinoderm classes: the echinoid Paracentrotus lividus, the asteroid Patiria miniata, and the holothuroid Parastichopus parvimensis. Using whole mount immunohistochemistry and confocal microscopy, we found that the nervous system of echinoid early juveniles is composed of three main structures: a basiepidermal nerve plexus, five radial nerve cords connected by a circumoral nerve ring, and peripheral nerves innervating the appendages. Our whole mount preparations further allowed us to obtain thorough descriptions of these structures and of several innervation patterns, in particular at the level of the appendages. Detailed comparisons of the echinoid juvenile nervous system with those of asteroid and holothuroid juveniles moreover supported a general conservation of the main neural structures in all three species. Our results sustain the hypotheses of previous work for the existence of two neural units in echinoderms: one consisting of the basiepidermal nerve plexus to process sensory stimuli locally, and one composed of the radial nerve cords and the peripheral nerves constituting a centralized control system. This study provides the basis of more in-depth comparisons of the echinoderm adult nervous system with those of other animals, in particular hemichordates and chordates, to address the long-standing controversies about deuterostome nervous system evolution.
View details for DOI 10.1002/cne.25012
View details for PubMedID 32841380