Biology subjects

Bobkov, Y.

Publications and source records attributed to Bobkov, Y..

3 recordsLinked to original sources

bioRxiv2026

Chemically mediated neural and behavioral responses in early benthic juvenile Caribbean spiny lobsters, Panulirus argus

Spiny lobsters use their chemical senses to acquire resources such as shelter and food, avoid predators, and interact with conspecifics. However, little is known about if and how these responses change over developmental stages. Here, we used early benthic juvenile stage Caribbean spiny lobsters, Panulirus argus, in calcium imaging studies to investigate physiological properties of olfactory receptor neurons in the olfactory organ, i.e., the antennules, and in behavioral studies to characterize chemically triggered responses. The basic structural organization of the antennules is similar in early benthic juvenile, older juvenile, and adult lobsters. Our calcium imaging studies show that the olfactory receptor neurons of both life stages have generally similar patterns of spontaneous activity, tuning characteristics, sensitivity, and kinetic parameters of responses to chemicals. Our behavioral studies show that early benthic juvenile spiny lobsters have similar behaviors to adults in that they produce currents following stimulation with food-related chemicals, navigate through the chemical plumes to locate the source of food-related chemicals, show alarm responses to conspecific hemolymph, and groom their antennules following stimulation with L-glutamate. Our findings suggest that features of the olfactory organ and its sensory neurons and the behavioral patterns are generally similar across developmental stages, making early benthic juvenile lobsters a favorable model for studying chemosensory transduction, coding mechanisms, and chemical-driven behaviors. The smaller scale of early benthic juvenile lobsters allows the use of compact, miniature benchtop laboratory setups, offering significant flexibility for medium-throughput basic and applied studies.

animal behavior and cognition↗

bioRxiv2022

Independent innexin radiation shaped signaling in ctenophores.

Innexins facilitate cell-cell communication by forming gap junctions or non-junctional hemichannels, which play important roles in metabolic, chemical, ionic, and electrical coupling. The lack of knowledge regarding the evolution and role of these channels in ctenophores (comb jellies), the likely sister group to the rest of animals, represents a substantial gap in our understanding of the evolution of intercellular communication in animals. Here we identify and phylogenetically characterize the complete set of innexins of four ctenophores: Mnemiopsis leidyi, Hormiphora californensis, Pleurobrachia bachei, and Beroe ovata. Our phylogenetic analyses suggest that ctenophore innexins diversified independently from those of other animals and were established early in the emergence of ctenophores. We identified a four-innexin genomic cluster, which was present in the last common ancestor of these four species and has been largely maintained in these lineages. Evidence from correlated spatial and temporal gene expression of the M. leidyi innexin cluster suggest that this cluster has been maintained due to constraints related to gene regulation. We describe basic electrophysiological properties of putative ctenophore hemichannels from muscle cells using intracellular recording techniques, showing substantial overlap with the properties of bilaterian innexin channels. Together, our results suggest that the last common ancestor of animals had gap junctional channels also capable of forming functional innexin hemichannels, and that innexin genes have independently evolved in major lineages throughout Metazoa.

evolutionary biology↗

bioRxiv2018

The radial expression of dorsal-ventral patterning genes in placozoans, Trichoplax adhaerens, argues for an oral-aboral axis

The placozoans are a morphologically simplistic group of marine animals found globally in tropical and subtropical environments. They consist of a single named species, Trichoplax adhaerens and have roughly six morphologically distinct cell types. With a sequenced genome, a limited number of cell-types and a simple flattened morphology, Trichoplax is an ideal model organism to understand cellular dynamics and tissue patterning in the first animals. Using new approaches for identification of gene expression patterns this research looks at the relationship of Chordin/TgfB signaling and the axial patterning system of Placozoa. Our results suggest that placozoans have an oral-aboral axis similar to cnidarians and that the parahoxozoan ancestor (common ancestor of Placozoa and Cnidaria) was likely radially symmetric.

developmental biology↗