Background: Although the overall brain organization is shared in vertebrates, there are significant differences within subregions among different groups, notably between Sarcopterygii (lobe-finned fish) and Actinopterygii (ray-finned fish). Recent comparative studies focusing on the ventricular morphology have revealed a large diversity of the hypothalamus. Here, we study the development of the inferior lobe (IL), a prominent structure forming a bump on the ventral surface of the teleost brain. Based on its position, IL has been thought to be part of the hypothalamus (therefore forebrain).
Results: Taking advantage of genetic lineage-tracing techniques in zebrafish, we reveal that cells originating from her5-expressing progenitors in the midbrain-hindbrain boundary (MHB) participate in the formation of a large part of the IL. 3D visualization demonstrated how IL develops in relation to the ventricular system. We found that IL is constituted by two developmental components: the periventricular zone of hypothalamic origin and the external zone of mesencephalic origin. The mesencephalic external zone grows progressively until adulthood by adding new cells throughout development.
Conclusion: Our results disprove a homology between the IL and the mammalian lateral hypothalamus. We suggest that the IL is likely to be involved in multimodal sensory integration rather than feeding motivation. The teleost brain is not a simpler version of the mammalian brain, and our study highlights the evolutionary plasticity of the brain which gives rise to novel structures.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6407210 | PMC |
| http://dx.doi.org/10.1186/s12915-019-0631-y | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Are oligodendrocytes bystanders or drivers of Parkinson's disease pathology?
PLoS Biol
January 2025
Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.
The major pathological feature of Parkinson 's disease (PD), the second most common neurodegenerative disease and most common movement disorder, is the predominant degeneration of dopaminergic neurons in the substantia nigra, a part of the midbrain. Despite decades of research, the molecular mechanisms of the origin of the disease remain unknown. While the disease was initially viewed as a purely neuronal disorder, results from single-cell transcriptomics have suggested that oligodendrocytes may play an important role in the early stages of Parkinson's.
View Article and Find Full Text PDFMesolimbic dopamine neurons drive infradian rhythms in sleep-wake and heightened activity state.
Sci Adv
January 2025
Douglas Mental Health University Institute, McGill University, Montreal, QC H4H 1R3, Canada.
Infradian mood and sleep-wake rhythms with periods of 48 hours and beyond have been observed in patients with bipolar disorder (BD), which even persist in the absence of exogenous timing cues, indicating an endogenous origin. Here, we show that mice exposed to methamphetamine in drinking water develop infradian locomotor rhythms with periods of 48 hours and beyond which extend to sleep length and manic state-associated behaviors in support of a model for cycling in BD. The cycling capacity is abrogated upon genetic disruption of dopamine (DA) production in DA neurons of the ventral tegmental area (VTA) or ablation of nucleus accumbens projecting DA neurons.
View Article and Find Full Text PDFIdentification of an early subset of cerebellar nuclei neurons in mice.
Elife
December 2024
Department of Human Anatomy and Cell Science, The Children's Hospital Research Institute of Manitoba (CHRIM), Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada.
Cerebellar nuclei (CN) neurons serve as the primary output of the cerebellum and originate from the cerebellar primordium at early stages of cerebellar development. These neurons are diverse, integrating information from the cerebellar cortex and relaying it to various brain regions. Employing various methodologies, we have characterized a specific subset of CN neurons that do not originate from the rhombic lip or ventricular zone of the cerebellar primordium.
View Article and Find Full Text PDFThe cation channel mechanisms of subthreshold inward depolarizing currents in the mice VTA dopaminergic neurons and their roles in the chronic-stress-induced depression-like behavior.
Elife
December 2024
Department of Pharmacology, Hebei Medical University, Shijiazhuang, China.
The slow-intrinsic-pacemaker dopaminergic (DA) neurons originating in the ventral tegmental area (VTA) are implicated in various mood- and emotion-related disorders, such as anxiety, fear, stress and depression. Abnormal activity of projection-specific VTA DA neurons is the key factor in the development of these disorders. Here, we describe the crucial role of the NALCN and TRPC6, non-selective cation channels in mediating the subthreshold inward depolarizing current and driving the firing of action potentials of VTA DA neurons in physiological conditions.
View Article and Find Full Text PDFFunctional Adaptation in the Brain Habenulo-Mesencephalic Pathway During Cannabinoid Withdrawal.
Cells
November 2024
Neuroscience Institute, Section of Cagliari, National Research Council of Italy, Cittadella Universitaria di Monserrato, I-09042 Cagliari, Italy.
The mesolimbic reward system originating from dopamine neurons in the ventral tegmental area (VTA) of the midbrain shows a profound reduction in function during cannabinoid withdrawal. This condition may underlie aversive states that lead to compulsive drug seeking and relapse. The lateral habenula (LHb) exerts negative control over the VTA via the GABA rostromedial tegmental nucleus (RMTg), representing a potential convergence point for drug-induced opponent processes.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!