Hongbo Jia

Urination, a vital and conserved process of emptying urine from the urinary bladder in mammals, requires precise coordination between the bladder and external urethral sphincter (EUS) that is tightly controlled by a complex neural network. However, the specific subpopulation of neurons that accounts for such coordination remains unidentified, limiting the development of target-specific therapies for certain urination disorders, for example, detrusor–sphincter dyssynergia. Here, we find that cells expressing estrogen receptor 1 (ESR1 ⁺ ) in the pontine micturition center (PMC) initiate voiding when activated and suspend ongoing voiding when suppressed, each at 100% reliability. Transection of the pelvic nerve does not impair PMC ^ESR1+ neurons’ control of the EUS via the pudendal nerve, whereas transection of the pudendal nerve does not impair their control of the bladder via the pelvic nerve. Anatomically, PMC ^ESR1+ neurons consist of three distinct spinal-projection-based subpopulations: one targeting the sacral parasympathetic nucleus, one innervating the dorsal gray commissure, and a third that projects to both regions, thereby enforcing the coordination of bladder contraction and sphincter relaxation in a rigid temporal sequence. Thus, we identify a cell type in the brainstem that controls the bladder–urethra coordination for urination.

Urination, a vital and conserved process of emptying urine from the urinary bladder in mammals, requires precise coordination between the bladder and external urethral sphincter (EUS) that is tightly controlled by a complex neural network. However, the specific subpopulation of neurons that accounts for such coordination remains unidentified, limiting the development of target-specific therapies for certain urination disorders, e.g., detrusor-sphincter dyssynergia. Here, we find that cells expressing estrogen receptor 1 (ESR1+) in the pontine micturition center (PMC) initiate voiding when activated and suspend ongoing voiding when suppressed, each at 100% reliability. Transection of the pelvic nerve does not impair PMCESR1+ neurons’ control of the EUS via the pudendal nerve, whereas transection of the pudendal nerve does not impair their control of the bladder via the pelvic nerve. Anatomically, PMCESR1+ neurons consist of three distinct spinal-projection-based subpopulations: one targeting the sacral parasympathetic nucleus (SPN), one innervating the dorsal gray commissure (DGC), and a third that projects to both regions, thereby enforcing the coordination of bladder contraction and sphincter relaxation in a rigid temporal sequence. Thus, we identify a cell type in the brainstem that controls the bladder-urethra coordination for urination.

Observing the activity patterns of large neural populations throughout the brain is essential for understanding brain function. However, capturing neural interactions across widely distributed brain regions from both superficial and deep cortical layers remains challenging with existing microscopy technologies. Here, we introduce a state-of-the-art two-photon microscopy system, ULTRA, capable of single-cell resolution imaging across an ultra-large field of view (FOV) exceeding 50 mm², enabling deep and wide field in vivo imaging. To demonstrate its capabilities, we conducted a series of experiments under multiple imaging conditions, successfully visualizing brain structures and neuronal activities spanning a spatial range of over 7 mm from superficial layers to depths of up to 900 μm, while covering a volume of 45.24 mm ³ in the mouse brain. This versatile imaging platform overcomes traditional spatial constraints, providing a powerful tool for comprehensive exploration of neuronal circuitry over extensive spatial scales with cellular resolution.

SignificanceIn mesoscopic imaging research in neuroscience, achieving high spatial resolution optical imaging across the entire field of view (FOV) remains critical. This directly determines whether researchers can precisely analyze the large-scale dynamic activities of neural circuits at the single-cell or even subcellular level. Consistent optical quality throughout the entire imaging FOV is essential to accurately capture the spatiotemporal patterns of neural activity across brain regions, thereby providing a powerful tool for understanding the circuit mechanisms underlying cognition, behavior, and disease at cellular and subcellular resolution in vivo.AimThis study aims to develop a technology that extends the imaging FOV in a two-photon mesoscope while enhancing the optical quality across the entire FOV in vivo. The key point is to establish a robust method that can significantly extend the FOV beyond what the micro/mesoscope objective had been originally designed for, yet maintain the original resolution specifications. As such, the value of the method also extends beyond improving just one mesoscope, which we use as a demo in this study.ApproachThis study introduces an innovative approach that combines block scanning with adaptive optical (AO) correction through a bioinspired honeycomb-based cellular multipoint adaptive technology (CMAT) to achieve mesoscopic two-photon imaging. This system enables unprecedented large-FOV, high-resolution imaging by dividing an 8×8 mm2 imaging area into subregions, each pre-optimized with deformable mirror (DM) compensation while applying real-time dynamic wavefront correction during scanning. Furthermore, we have designed multiple user-defined sub-region scanning functions. Each sub-region automatically loads the aberration correction compensation values from the nearest reference point relative to its center, thereby ensuring optimal optical performance for every individual sub-region. The robustness of this technology has been systematically verified across multiple neural circuit observation scenarios using transgenic mouse models, demonstrating its capability for reliable single-cell resolution imaging across extensive brain regions.ResultsComprehensive evaluation using standard samples and transgenic mouse models demonstrated that the CMAT significantly enhances the imaging performance of the two-photon mesoscope. This technique extends the effective two-photon imaging FOV from 6×6 mm2 to 8×8 mm2 while markedly improving the optical quality in the peripheral regions. High resolution was maintained at ∼1 μm (lateral) and ∼10 μm (axial) in the central area, with edge regions achieving improved resolutions of ∼1.3 μm (lateral) and ∼14 μm (axial). Quantitative analysis confirmed that multipoint AO not only enhances image contrast and optical resolution but also substantially increases the signal-to-noise ratio (SNR) in Ca2+ imaging. This work delivers a pivotal technical advance for large-scale functional imaging of neural circuits.ConclusionCMAT significantly extends the effective FOV and enhances the optical quality of the two-photon mesoscope system.

Brain stimulation therapies have been increasingly applied to treat patients with drug-resistant epilepsy or other neuropsychiatric disorders, but identifying effective stimulation targets appropriate for individual patients remains challenging. Using intracranial electrophysiological recordings, we found that fast ripple (FR) activity was tightly correlated with the severity of consciousness impairment during seizures in patients with drug-resistant, consciousness-staged epilepsy. Epileptic network analysis based on FR coincidence across brain regions revealed hubs of ictal FR activity, defined as highly connected nodes, specific to individual patients. A small, exploratory study on eight patients with drug-resistant epilepsy showed that stimulating these hubs reduced FRs, ameliorated consciousness impairments, and reduced seizures during a poststimulation time window of up to 11 days. Moreover, FR hub stimulation showed a lower risk of evoking seizures than stimulating seizure onset zones, a now approved treatment option. These results suggest a potentially safe and effective strategy to alleviate epileptic seizures by stimulating patient-specific FR network hubs.

Previous studies based on layer specificity suggest that ascending signals from the thalamus to the sensory neocortex preserve spatially organized information, but it remains unknown whether sensory information descending from sensory neocortex to the thalamus also maintains such spatial organization pattern. By focusing on projection specificity, we mapped the tone response properties of two groups of cortical neurons in the primary auditory cortex (A1), based on the relationship between their specific connections to other regions and their function in ascending (thalamocortical recipient [TR] neurons) or descending (corticothalamic [CT] neurons) auditory information. A clear tonotopic gradient was observed among TR neurons, but not CT neurons. Additionally, CT neurons exhibited markedly higher heterogeneity in their frequency tuning and had broader bandwidth than TR neurons. These results reveal that the information flow descending from A1 to the thalamus via CT neurons is not arranged tonotopically, suggesting that the descending information flow possibly contributes to higher-order feedback processing of diverse auditory inputs.

Previous studies based on layer specificity suggest that ascending signals from the thalamus to the sensory neocortex preserve spatially organized information, but it remains unknown whether sensory information descending from sensory neocortex to the thalamus also maintains such spatial organization pattern. By focusing on projection specificity, we mapped the tone response properties of two groups of cortical neurons in the primary auditory cortex (A1), based on the relationship between their specific connections to other regions and their function in ascending (thalamocortical recipient, TR neurons) or descending (corticothalamic, CT neurons) auditory information. A clear tonotopic gradient was observed among TR neurons, but not CT neurons. Additionally, CT neurons exhibited markedly higher heterogeneity in their frequency tuning and had broader bandwidth than TR neurons. These results reveal that the information flow descending from A1 to the thalamus via CT neurons is not arrange tonotopically, suggesting that the descending information flow possibly contributes to higher-order feedback processing of diverse auditory inputs.

SUMMARY: The postmitotic nature, exceptional longevity, and elaborate cytoarchitecture of neurons exert extraordinary demands on proteostasis and autophagy regulation. Amphisomes are organelles of the autophagy pathway that result from the fusion of autophagosomes with late endosomes. Previous work suggests that neuronal amphisomes also serve as signalling platforms, though their physiological relevance in vivo remains largely unexplored. Here, we demonstrate dynamic trafficking of amphisomes within the long-range, highly branched axons of locus coeruleus norepinephrine ( LC-NE ) neurons. Using in vivo photoconversion, we show that amphisomes originating in distal axons can traverse the entire axonal length to reach the soma. Two-photon imaging of LC-NE projections to the prefrontal cortex revealed that velocity and directionality of trafficking are tightly regulated by LC activity states, behavioural context, and autocrine norepinephrine signalling. Activation of Gi-coupled receptor signalling unifies directionality of transport, enhances somatic cargo delivery, whereas prolonged distal immobilization correlates with increased norepinephrine release, consistent with a signalling function. Together, these findings establish LC amphisomes as dual-function organelles that integrate degradative transport with activity-dependent signalling in vivo . Highlights: - Amphisomes are present within the distal axons of locus coeruleus norepinephrine neurons - Distally generated amphisomes traverse the entire axonal length to reach the soma in vivo - Velocity and directionality of trafficking are regulated by LC activity, behavioural context, and autocrine norepinephrine signalling - Prolonged distal amphisome pausing correlates with increased norepinephrine release