Synaptic plasticity is widely implicated in learning and brain-state regulation. Although correlations between synaptic modifications and diverse brain functions have been extensively reported, establishing causality requires tools that can directly and selectively perturb synapses in vivo. Recently, the chemogenetic actuator SYNCit-K (SynK) enabled causal induction of dendritic spine enlargement and synaptic potentiation. However, SynK relies on the coexpression of two independent components delivered by separate viral vectors, making it difficult to reliably achieve appropriate expression levels of both components within the same neuron. Here, using neocortical dissociated cultures from mouse embryos of undetermined sex, we sought to develop a unified, single-vector version of SynK (uniSynK) that enables robust and safe induction of dendritic spine enlargement. We first found that each SynK component induces distinct, concentration-dependent abnormalities in neuronal morphology when overexpressed, underscoring the need for precise control of their expression ratio. To address this challenge, we engineered a single construct in which the two components are linked by internal ribosome entry site (IRES) variants with graded translational efficiencies. Systematic screening of IRES variants identified an optimized configuration that preferentially drives each component within its respective concentration range that preserves normal spine morphology. The optimized uniSynK efficiently induces dendritic spine enlargement while exhibiting fewer off-target morphological abnormalities than observed in the multivector system when expression levels were not properly controlled. By simplifying experimental design, this single-vector, ratio-optimized synaptic chemogenetic tool provides a practical and broadly applicable platform that should facilitate causal interrogation of synaptic plasticity across neural circuits and behavior.

Synaptic plasticity is widely implicated in learning and brain-state regulation. Although correlations between synaptic modifications and diverse brain functions have been extensively reported, establishing causality requires tools that can directly and selectively perturb synapses in vivo. Recently, the chemogenetic actuator SYNCit-K (SynK) enabled causal induction of dendritic spine enlargement and synaptic potentiation. However, SynK relies on the coexpression of two independent components delivered by separate viral vectors, making it difficult to reliably achieve appropriate expression levels of both components within the same neuron. Here, using neocortical dissociated cultures from mouse embryos of undetermined sex, we sought to develop a unified, single-vector version of SynK (uniSynK) that enables robust and safe induction of dendritic spine enlargement. We first found that each SynK component induces distinct, concentration-dependent abnormalities in neuronal morphology when overexpressed, underscoring the need for precise control of their expression ratio. To address this challenge, we engineered a single construct in which the two components are linked by internal ribosome entry site (IRES) variants with graded translational efficiencies. Systematic screening of IRES variants identified an optimized configuration that preferentially drives each component within its respective concentration range that preserves normal spine morphology. The optimized uniSynK efficiently induces dendritic spine enlargement while exhibiting fewer off-target morphological abnormalities than observed in the multivector system when expression levels were not properly controlled. By simplifying experimental design, this single-vector, ratio-optimized synaptic chemogenetic tool provides a practical and broadly applicable platform that should facilitate causal interrogation of synaptic plasticity across neural circuits and behavior.

Single-cell RNA sequencing (scRNA-seq) is fundamentally reshaping the research paradigm of mosquito biology and host-pathogen interactions via its high-resolution transcriptomic profiling capability. This review first outlines the technical workflow and data analysis strategies of scRNA-seq, then highlights key applications of scRNA-seq in constructing mosquito cell atlases, deciphering post-blood-meal transcriptional remodeling, sexual dimorphism, and receptor coexpression patterns....

Background/aims To explore the roles of insulin-like growth factor 1 receptor (IGF1R) and thyroid-stimulating hormone receptor (TSHR) in extraocular muscle pathology.Methods Extraocular muscle specimens were obtained during rectus muscle myectomy surgeries performed for large-angle strabismus correction in patients with thyroid-associated orbitopathy (TAO) and during rectus muscle resection surgeries performed for congenital strabismus in normal controls. Immunohistochemistry was employed to detect and compare between-group IGF1R and TSHR expression; ImageJ software was used to assess the staining area and H&E staining was used to evaluate morphological differences in tissues. Intergroup comparisons were conducted using the Mann-Whitney U test.Results Histological examination of the extraocular muscle specimens revealed greater fibrosis in the TAO group (n=12) than in the control group (n=6). Immunohistochemistry (IHC) revealed significantly higher expression of both IGF1R and TSHR in the TAO group, particularly in elongated fibroblast-like cells and some myocytes, than in the control group, which exhibited minimal expression. Semiquantitative analysis confirmed significantly larger mean expression areas for IGF1R and TSHR in the TAO group than in the control group (p

Dengue mosquito olfactory neurons are known to show complex patterns of receptor expression, but the details of this complexity remain unclear. Here, the authors build a comprehensive molecular atlas ...

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Drosophila olfactory sensory neurons tend to express a single ligand-specific receptor, following a one-receptor-per-neuron rule expected to apply broadly across insects. Recent work challenges this view by showing that some neurons in the mosquito Aedes aegypti coexpress multiple receptors. However, the full extent and nature of coexpression in Ae. aegypti remains unclear. We sequenced the transcriptomes of 46,000 female antennal neurons to resolve all olfactory neuron subtypes and identify...

Everyone knows that linguistic forms often (seem to) have multiple meanings: Sentences may be ambiguous, words often exhibit polysemy, they may be homonymous, and grammatical markers can have a range of uses. But more recently, two additional terms have become widespread in comparative approaches: colexification (the possibility of using a word with different senses) and…

Previous RNA profiling studies revealed coexpression of overlapping sense/antisense (s/a) transcripts in pro- and eukaryotic organisms. Functional analyses in yeast have shown that certain s/a mRNA/mR...

Serine protease cascades regulate key innate immune responses. Their activation cleaves a series of inactive protease zymogens, which then activate...