T cells suddenly appeared in jawed fish ∼450 million years ago. Biological studies of fish T cells may provide helpful evidence to understand evolution of adaptive immune systems. To this end, using a Nile tilapia (Oreochromis niloticus) model, we revealed the regulatory mechanism of adaptive immunity mediated by ancestral T cells in jawed fish. Nile tilapia T cells as well as a tightly regulated mammalian/mechanistic target of rapamycin complex 1 (mTORC1) pathway participate in the cellular adaptive immune response during Streptococcus agalactiae infection. Blockade of mTORC1 signaling by rapamycin impairs T cell activation and Ag-induced proliferation in this early vertebrate. More critically, we show that signals from mTORC1 are indispensable for primordial effector T cells to eliminate infection by promoting the expression of proinflammatory cytokines, cytotoxic-related molecules, and proapoptotic genes. Mechanistically, teleost mTORC1 directs effector T cell function by coordinating multiple metabolic programs, including glycolysis, glutaminolysis, and lipogenesis through activating key transcription factors c-Myc, HIF-1a, and sterol regulatory element-binding proteins, and thus links immune signals to metabolic reprogramming in jawed fish. To our knowledge, these results represent the first description of the regulatory mechanism for T cell-mediated adaptive immunity in a fish species. From an evolutionary viewpoint, our study suggests that primordial T cells are armed with sophisticated regulatory strategies like those in modern T cells prior to the divergence of bony fish from the tetrapod lineage. Therefore, our findings fill in an important gap regarding evolution of the adaptive immune system.

Many insects metamorphose from antagonistic larvae into mutualistic adult pollinators, with reciprocal adaptation leading to specialized insect-plant associations.It remains unknown how such interactions are established at molecular level. Here we assembled high-quality genomes of a fig species, Ficus pumila var. pumila, and its specific pollinating wasp, Wiebesia pumilae. We combined multi-omics with validation experiments to reveal molecular mechanisms underlying this specialized interaction. In the plant, we identified the specific compound attracting pollinators and validated the function of several key genes regulating its biosynthesis. In the pollinator, we found a highly reduced number of odorant-binding protein (OBP) genes and an OBP mainly binding the attractant. During antagonistic interaction, we found similar chemical profiles and turnovers throughout the development of galled ovules and seeds, and a significant contraction of detoxification-related gene families in the pollinator. Our study detects some key genes bridging coevolved mutualists, establishing expectations for more diffuse insect-pollinator systems.

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A two-terminal artificial synaptic device based on functionalized polythiophene nanowires network is fabricated and successfully used to emulate important biological synaptic functions, including PPF, SRDP and STDP.

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