Cholinergic interneurons (CINs) are essential elements of striatal circuits and functions. Although acetylcholine signaling via muscarinic receptors (mAChRs) has been well studied, more recent data indicate that postsynaptic nicotinic receptors (nAChRs) located on striatal GABAergic interneurons (GINs) are equally critical. One example is that CIN stimulation induces large disynaptic inhibition of striatal projection neurons (SPNs) mediated by nAChR activation of GINs. Although these circuits are ideally positioned to modulate striatal output, the neurons involved are not definitively identified because of an incomplete mapping of CINs-GINs interconnections. Here, we show that CINs modulate four GINs populations via an intricate mechanism involving co-activation of presynaptic and postsynaptic mAChRs and nAChRs. Using optogenetics, we demonstrate the participation of tyrosine hydroxylase-expressing GINs in the disynaptic inhibition of SPNs via heterotypic electrical coupling with neurogliaform interneurons. Altogether, our results highlight the importance of CINs in regulating GINs microcircuits via complex synaptic/heterosynaptic mechanisms.

Voltage imaging has emerged as a powerful tool for recording membrane potential changes in living cells, offering a direct measurement of rapid neuronal events with high temporal precision. Since the brain is a three-dimensional circuit, it is essential to record signals across a volume. However, achieving effective three-dimensional voltage imaging over large neuronal populations remains challenging due to the need for high imaging speed, high signal-to-noise ratio, and extensive volume coverage. In this study, we demonstrate in vivo three-dimensional voltage imaging in larval zebrafish using oblique plane microscopy and QFDBD-QUAS-driven expression of the genetically encoded voltage indicator Ace-mNeon2-Kv2.1, achieving volumetric imaging rates of up to 200 volumes per second (VPS). This approach enables dye-free voltage imaging, simplifying experimental workflows and improving the reproducibility of in vivo voltage imaging experiments for investigating neuronal circuit dynamics in the living zebrafish animal model.

The neurotransmitter acetylcholine (ACh) is essential in both the central and peripheral nervous systems. Recent studies highlight the significance of interactions between ACh and various neuromodulators in regulating complex behaviors. The ability to simultaneously image ACh and other neuromodulators can provide valuable information regarding the mechanisms underlying these behaviors. Here we developed a series of red fluorescent G-protein-coupled receptor activation-based ACh sensors, with a wide detection range and expanded spectral profile. The high-affinity sensor rACh1h reliably detects ACh release in various brain regions, including the nucleus accumbens, amygdala, hippocampus and cortex. Moreover, rACh1h can be coexpressed with green fluorescent sensors to record ACh release together with other neurochemicals in various behavioral contexts using fiber photometry, mesoscopic imaging and two-photon imaging with high spatiotemporal resolution.

Basal Ganglia Advances is a collection highlighting research on the structure, function, and disorders of the basal ganglia. It features studies spanning neuroscience, clinical insights, and computational models, serving as a hub for advances in movement, cognition, and behavior.

Recent advances in the field of Voltage Imaging, with a special focus on new constructs and novel implementations.

Work related to place tuning, spatial navigation, orientation and direction. Mainly includes articles on connectivity in the hippocampus, retrosplenial cortex, and related areas.

Intron retention (IR) is the molecular phenomenon by which introns, historically thought to represent non-coding 'junk', remain unspliced within pre-mRNA transcripts, resulting in their incorporation into the mature mRNA molecule. While the role of IR is well established in species of plant, fungi, insects and viruses, it remains relatively understudied in mammalian biology. It was previously assumed that IR only played a limited role in downregulating a transcript's translation potential through downstream initiation of nuclear detention or nonsense mediated decay (NMD). However, recent studies highlight IR's significantly more complex and dynamic contribution to cellular physiology and disease. In particular, a role for IR is emerging in both health and neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), a rapidly progressive and invariably fatal disease that renders patients paralysed and unable to eat, speak or breathe. Significant technological advances now permit a comprehensive interrogation of previously unrecognized aspects of RNA metabolism in clinically relevant human cell types. In this review, we focus on the differential role(s) of nuclear and cytoplasmic intron retaining transcripts (nIRTs and cIRTs, respectively), as well as how IRTs may influence subcellular localization of ribonucleoprotein (RNP) complexes, loss of function of bound RNA binding proteins (RBPs) and liquid-liquid phase separation (LLPS) in physiology and disease. Additionally, we discuss the potential of IRTs as independent regulatory elements beyond their protein-coding functions and highlight how artificial intelligence is poised to accelerate discoveries in this area. In the context of IR's increasing appreciation, we also highlight its potential as a therapeutic target and explore current and future challenges in this burgeoning field.