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Biology subjects

Uesaka, N.

Publications and source records attributed to Uesaka, N..

7 recordsLinked to original sources

Viral vectors with cluster of differentiation gene promoters to target specific cell types in the brain

Understanding brain function and developing targeted therapies for neurological disorders require precise access to specific cell types, but current methods are limited. Here, we report the development of cell-type specific adeno-associated virus (AAV) vectors utilizing promoters of cluster of differentiation genes (CD promoters) for targeted gene delivery in the brain. We newly identified CD promoters that induce gene expression selectively in specific cell types in the mouse brain. These AAVs enable in vivo calcium imaging and chemogenetic applications in specific cerebellar cells, revealing distinct and shared roles of two types of cerebellar interneurons. Notably, chemogenetic modulation of cerebellar molecular layer interneurons using a CD promoter rescued social behavior and motor deficits in a mouse model of autism spectrum disorder. Our findings demonstrate the utility of these AAVs in elucidating the functions of individual cell types in brain function and in developing novel, cell-type specific therapies for brain diseases.

neuroscience↗

Oligodendrocyte dependent synchronized activity orchestrates circuit maturation and brain functionalization

Synchronized spontaneous neural activity is a fundamental feature of developing central nervous systems and is thought to be essential for proper brain development. However, the mechanisms that regulate this synchronization and its long-term impact on brain function remain unclear. Here, we identify a previously unrecognized role of oligodendrocytes in orchestrating synchronized spontaneous activity during a critical developmental window, with lasting consequences for adult behavior. Using oligodendrocyte-specific genetic manipulation in the mouse cerebellum, we demonstrate that oligodendrocyte deficiency during early postnatal development, but not after weaning, disrupts the synchronization of Purkinje cell activity both during development and in adulthood. The early disruption produced persistent deficits in cerebellar-dependent behaviors, including anxiety, sociality, and motor function. Optogenetic re-synchronization in adulthood restored motor and social functions but not anxiety-like behavior, demonstrating that reduced Purkinje cell synchrony specifically drives the motor and social impairments. Our findings establish a causal link between developmental oligodendrocyte-regulated neural synchrony and the emergence of complex brain functions, which depend on the proper developmental trajectory necessary for driving brain function.

neuroscience↗

Innate liking and disgust reactions elicited by intraoral capsaicin in male mice

Liking and disgust are the primary positive and negative emotions, respectively, and are crucial for nutrient intake and toxin avoidance. These emotions are induced by multimodal stimuli such as taste, olfactory, and somatosensory inputs, and their dysregulation is evident in various psychiatric disorders. To understand the biological basis of liking and disgust, it is crucial to establish an animal model that allows for quantitative estimation of liking and disgust in response to multimodal stimuli. The only readout shared by many species, including humans, for liking and disgust, has been taste reactivity. However, readouts of non-taste stimuli-induced emotions remain unestablished. Here, we show that intraoral administration of capsaicin, a chemosomatosensory stimulus, elicits orofacial and bodily reactions in male mice similar to those observed in taste reactivity. Capsaicin induced liking reactions at low concentrations and disgust reactions at high concentrations. Capsaicin-induced disgust reactions consisted of various reactions, including gape and forelimb flail, with the proportion of each reaction among the disgust reactions being similar to that induced by bitter and sour stimuli. These findings indicate that orofacial and bodily reactions, defined as taste reactivity, are elicited not only by taste stimuli, but also by intraoral chemosomatosensory stimuli. Understanding the biological basis of capsaicin-induced orofacial and bodily reactions will advance our understanding of the fundamental mechanisms underlying liking and disgust across sensory modalities.

animal behavior and cognition↗

Automatic quantification of disgust taste reactivity in mice using machine learning

Disgust, a primary negative emotion, plays a vital role in protecting organisms from intoxication and infection. In rodents, this emotion has been quantified by measuring the specific reactions elicited by exposure to unpleasant tastes. These reactions were captured on video and manually analyzed, a process that required considerable time and effort. Here we developed a method to automatically count disgust reactions in mice by using machine learning. The disgust reactions were automatically tracked using DeepLabCut as the coordinates of the nose and both front and rear paws. The automated tracking data were split into test and training data, and the latter were combined with manually labeled data on whether a disgust reaction was present and, if so, which type of disgust reaction was present. Then, a random forest classifier was constructed, and the performance of the classifier was evaluated in the test dataset. The total number of disgust reactions estimated by the classifier highly correlated with those counted manually (Pearsons r = 0.98). The present method will decrease the time and effort required to analyze disgust reactions, thus facilitating the implementation of the taste reactivity test in large-scale screening and long-term experiments that necessitate quantifying a substantial number of disgust reactions.

bioinformatics↗

Whole-Brain Three-Dimensional Imaging of RNAs at Single-Cell Resolution

Whole-brain three-dimensional (3D) imaging is desirable to obtain a comprehensive and unbiased view of architecture and neural circuitry. However, current spatial analytic methods for brain RNAs are limited to thin sections or small samples. Here, we combined multiple new techniques to develop TRIC-DISCO, a new pipeline that allows imaging of RNA spatial distributions in whole adult mouse brains. First, we developed Tris-mediated retention of in situ hybridization signal during clearing (TRIC), which produces highly transparent tissue while maintaining the RNA signal intensities. We then combined TRIC with DISCO clearing (TRIC-DISCO) by controlling temperature during the in situ hybridization chain reaction (isHCR) to ensure uniform whole-brain staining. This pipeline eliminates the requirements for both strict RNase-free environments and workflow-compatible RNase inhibitors. Our TRIC-DISCO pipeline enables simple and robust, single-cell, whole-brain, 3D imaging of transcriptional signatures, cell-identity markers, and noncoding RNAs across the entire brain.

neuroscience↗

ATP activation of peritubular cells drives testicular sperm transport

Spermatogenesis, the complex developmental process of male germ cell proliferation, differentiation, and maturation, is the basis of male fertility and reproductive fitness. In the seminiferous tubules of the testes, spermatozoa are constantly generated from spermatogonial stem cells through a stereotyped sequence of mitotic and meiotic divisions. The basic physiological principles, however, that control both maturation and luminal transport of the still immotile spermatozoa within the seminiferous tubules remain poorly, if at all, defined. Here, we show that coordinated contractions of smooth muscle-like testicular peritubular cells provide the propulsive force for luminal sperm transport towards the rete testis and epididymis. Using a mouse model for in vivo imaging, we describe and quantify spontaneous tubular contractions and show a causal relationship between peritubular Ca2+ waves and peristaltic transport. Moreover, we identify P2 receptor-dependent purinergic signaling pathways as physiological triggers of tubular contractions both in vitro and in vivo. When challenged with extracellular ATP, transport of luminal content inside the seminiferous tubules displays stage-dependent directionality. We thus suggest that paracrine purinergic signaling coordinates peristaltic recurrent contractions of the mouse seminiferous tubules to propel immotile spermatozoa to the rete testis. Consequently, our findings could have substantial pharmaceutical implications for both infertility treatment and / or male contraception.

cell biology↗

AUTS2 Governs Cerebellar Development, Purkinje Cell Maturation, Motor Function and Social Communication

Autism susceptibility candidate 2 (AUTS2), a risk gene for autism spectrum disorders (ASDs), is implicated in telencephalon development. Because AUTS2 is also expressed in the cerebellum where defects have been linked to ASDs, we investigated AUTS2 functions in the cerebellum. AUTS2 is specifically localized in Purkinje cells (PCs) and Golgi cells during postnatal development. Auts2 conditional knockout (cKO) mice exhibited smaller and deformed cerebella containing immature-shaped PCs with reduced expression of Cacna1a. Auts2 cKO and knock-down experiments implicated AUTS2 participation in elimination and translocation of climbing fiber synapses, and restriction of parallel fiber synapse numbers. Auts2 cKO mice exhibited behavioral impairments in motor learning and vocal communications. Because Cacna1a is known to regulate synapse development in PCs, it suggests that AUTS2 is required for PC maturation to elicit normal development of PC synapses and thus the impairment of AUTS2 may cause cerebellar dysfunction related to psychiatric illnesses such as ASDs.

neuroscience↗