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Tanaka, Y.

Publications and source records attributed to Tanaka, Y..

3 recordsLinked to original sources

Reward revaluation biases hippocampal sequence content away from the preferred outcome

Internally generated sequences of place cell activity can depict spatial trajectories to reward locations, suggesting a role in model-based behavioral control. A largely separate literature emphasizes reward revaluation as the litmus test for such control, yet the content of hippocampal sequences under revaluation conditions is unknown. We report that the content of sharp wave-ripple hippocampal sequences is biased away from the preferred outcome following reward revaluation, challenging the idea that such sequences reflect recent experience or trajectories toward a goal.\n\nAcknowledgmentsWe thank Nancy Gibson, Martin Ryan and Jean Flanagan for animal care and MinChing Kuo, Julia Espinosa and Eric Carmichael for technical assistance. We thank Elyot Grant for developing the SWR detection method used for the main analyses in this paper. This work was supported by the University of Waterloo and Dartmouth College (start-up funds to MvdM), and the Netherlands Organization for Scientific Research (NWO, grant 863.10.013 to MvdM).\n\nAuthor contributionsAAC performed experiments and pre-processed the data. AAC, YT and MvdM wrote analysis code. AAC and MvdM performed data analysis. MvdM wrote the paper with comments from AAC and YT.\n\nConflict of InterestThe authors declare no competing financial interests.

neuroscience

Consortia of anti-nematode fungi and bacteria in the rhizosphere of soybean plants attacked by root-knot nematodes

Cyst and root-knot nematodes are major risk factors of agroecosystem management, often causing devastating impacts on crop production. The use of microbes that parasitize or prey on nematodes has been considered as a promising approach for suppressing phytopathogenic nematode populations. However, as effects and persistence of those biological control agents often vary substantially depending on regions, soil characteristics, and agricultural practices, more insights into microbial community processes are required to develop reproducible control of nematode populations. By performing high-throughput sequencing profiling of bacteria and fungi, we examined how root and soil microbiomes differ between benign and nematode-infected plant individuals in a soybean field in Japan. Results indicated that various taxonomic groups of bacteria and fungi occurred preferentially on the soybean individuals infected by root-knot nematodes. Based on a network analysis of potential microbe-microbe associations, we further found that several fungal taxa potentially preying on nematodes [Dactylellina (Orbiliales), Rhizophydium (Rhizophydiales), Clonostachys (Hypocreales), Pochonia (Hypocreales), and Purpureocillium (Hypocreales)] co-occurred in the soybean rhizosphere at a small spatial scale. Overall, this study suggests how \"consortia\" of anti-nematode microbes can derive from indigenous (resident) microbiomes, thereby providing basic information for managing anti-nematode microbial communities in agroecosystems.

microbiology

Establishment In Culture Of Expanded Potential Stem Cells

Mouse embryonic stem cells are derived from in vitro explantation of blastocyst epiblasts1,2 and contribute to both the somatic lineage and germline when returned to the blastocyst3 but are normally excluded from the trophoblast lineage and primitive endoderm4-6. Here, we report that cultures of expanded potential stem cells (EPSCs) can be established from individual blastomeres, by direct conversion of mouse embryonic stem cells (ESCs) and by genetically reprogramming somatic cells. Remarkably, a single EPSC contributes to the embryo proper and placenta trophoblasts in chimeras. Critically, culturing EPSCs in a trophoblast stem cell (TSC) culture condition permits direct establishment of TSC lines without genetic modification. Molecular analyses including single cell RNA-seq reveal that EPSCs share cardinal pluripotency features with ESCs but have an enriched blastomere transcriptomic signature and a dynamic DNA methylome. These proof-of-concept results open up the possibility of establishing cultures of similar stem cells in other mammalian species.

developmental biology