1
|
Kebschull JM, Casoni F, Consalez GG, Goldowitz D, Hawkes R, Ruigrok TJH, Schilling K, Wingate R, Wu J, Yeung J, Uusisaari MY. Cerebellum Lecture: the Cerebellar Nuclei-Core of the Cerebellum. CEREBELLUM (LONDON, ENGLAND) 2024; 23:620-677. [PMID: 36781689 PMCID: PMC10951048 DOI: 10.1007/s12311-022-01506-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/10/2022] [Indexed: 02/15/2023]
Abstract
The cerebellum is a key player in many brain functions and a major topic of neuroscience research. However, the cerebellar nuclei (CN), the main output structures of the cerebellum, are often overlooked. This neglect is because research on the cerebellum typically focuses on the cortex and tends to treat the CN as relatively simple output nuclei conveying an inverted signal from the cerebellar cortex to the rest of the brain. In this review, by adopting a nucleocentric perspective we aim to rectify this impression. First, we describe CN anatomy and modularity and comprehensively integrate CN architecture with its highly organized but complex afferent and efferent connectivity. This is followed by a novel classification of the specific neuronal classes the CN comprise and speculate on the implications of CN structure and physiology for our understanding of adult cerebellar function. Based on this thorough review of the adult literature we provide a comprehensive overview of CN embryonic development and, by comparing cerebellar structures in various chordate clades, propose an interpretation of CN evolution. Despite their critical importance in cerebellar function, from a clinical perspective intriguingly few, if any, neurological disorders appear to primarily affect the CN. To highlight this curious anomaly, and encourage future nucleocentric interpretations, we build on our review to provide a brief overview of the various syndromes in which the CN are currently implicated. Finally, we summarize the specific perspectives that a nucleocentric view of the cerebellum brings, move major outstanding issues in CN biology to the limelight, and provide a roadmap to the key questions that need to be answered in order to create a comprehensive integrated model of CN structure, function, development, and evolution.
Collapse
Affiliation(s)
- Justus M Kebschull
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21205, USA.
| | - Filippo Casoni
- Division of Neuroscience, San Raffaele Scientific Institute, and San Raffaele University, Milan, Italy
| | - G Giacomo Consalez
- Division of Neuroscience, San Raffaele Scientific Institute, and San Raffaele University, Milan, Italy
| | - Daniel Goldowitz
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, Canada
| | - Richard Hawkes
- Department of Cell Biology & Anatomy and Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, T2N 4N1, Canada
| | - Tom J H Ruigrok
- Department of Neuroscience, Erasmus MC, Rotterdam, the Netherlands
| | - Karl Schilling
- Department of Anatomy, Anatomy & Cell Biology, Rheinische Friedrich-Wilhelms-Universität, 53115, Bonn, Federal Republic of Germany
| | - Richard Wingate
- MRC Centre for Neurodevelopmental Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Joshua Wu
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, Canada
| | - Joanna Yeung
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, Canada
| | - Marylka Yoe Uusisaari
- Neuronal Rhythms in Movement Unit, Okinawa Institute of Science and Technology, 1919-1 Tancha, Onna-Son, Kunigami-Gun, Okinawa, 904-0495, Japan.
| |
Collapse
|
2
|
Wang T, Numata N, Ji Q, Mizuno Y, Viet NM, Luo Y, Chao Y, Panezai SK, Sugihara I. Single axonal characterization of trigeminocerebellar projection patterns in the mouse. J Comp Neurol 2024; 532:e25581. [PMID: 38289187 DOI: 10.1002/cne.25581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 12/23/2023] [Accepted: 12/30/2023] [Indexed: 02/01/2024]
Abstract
The cerebellar projection from the trigeminal nuclear complex is one of the major populations of the cerebellar inputs. Although this projection is essential in cerebellar functional processing and organization, its morphological organization has not been systematically clarified. The present study addressed this issue by lobule-specific retrograde neuronal labeling and single axonal reconstruction with anterograde labeling. The cerebellar projection arose mainly from the interpolaris subdivision of the spinal trigeminal nucleus (Sp5I) and the principal trigeminal sensory nucleus (Pr5). Although crus II, paramedian lobule, lobule IX, and simple lobule were the major targets, paraflocculus, and other lobules received some projections. Reconstructed single trigeminocerebellar axons showed 77.8 mossy fiber terminals on average often in multiple lobules but no nuclear collaterals. More terminals were located in zebrin-negative or lightly-positive compartments than in zebrin-positive compartments. While Pr5 axons predominantly projected to ipsilateral crus II, Sp5I axons projected either predominantly to crus II and paramedian lobule often bilaterally, or predominantly to lobule IX always ipsilaterally. Lobule IX-predominant-type Sp5I neurons specifically expressed Gpr26. Gpr26-tagged neuronal labeling produced a peculiar mossy fiber distribution, which was dense in the dorsolateral lobule IX and extending transversely to the dorsal median apex in lobule IX. The projection to the cerebellar nuclei was observed in collaterals of ascending Sp5I axons that project to the diencephalon. In sum, multiple populations of trigeminocerebellar projections showed divergent projections to cerebellar lobules. The projection was generally complementary with the pontine projection and partly matched with the reported orofacial receptive field arrangement.
Collapse
Affiliation(s)
- Tianzhuo Wang
- Department of Systems Neurophysiology, Tokyo Medical and Dental University Graduate School of Medical and Dental Sciences, Bunkyo-ku, Tokyo, Japan
| | - Naoyuki Numata
- Department of Systems Neurophysiology, Tokyo Medical and Dental University Graduate School of Medical and Dental Sciences, Bunkyo-ku, Tokyo, Japan
| | - Qing Ji
- Department of Systems Neurophysiology, Tokyo Medical and Dental University Graduate School of Medical and Dental Sciences, Bunkyo-ku, Tokyo, Japan
| | - Yuma Mizuno
- Department of Systems Neurophysiology, Tokyo Medical and Dental University Graduate School of Medical and Dental Sciences, Bunkyo-ku, Tokyo, Japan
| | - Nguyen-Minh Viet
- Department of Systems Neurophysiology, Tokyo Medical and Dental University Graduate School of Medical and Dental Sciences, Bunkyo-ku, Tokyo, Japan
- F. M. Kirby Neurobiology Center of Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Yuanjun Luo
- Department of Systems Neurophysiology, Tokyo Medical and Dental University Graduate School of Medical and Dental Sciences, Bunkyo-ku, Tokyo, Japan
| | - Yuhan Chao
- Department of Systems Neurophysiology, Tokyo Medical and Dental University Graduate School of Medical and Dental Sciences, Bunkyo-ku, Tokyo, Japan
| | - Saddam Khan Panezai
- Department of Systems Neurophysiology, Tokyo Medical and Dental University Graduate School of Medical and Dental Sciences, Bunkyo-ku, Tokyo, Japan
| | - Izumi Sugihara
- Department of Systems Neurophysiology, Tokyo Medical and Dental University Graduate School of Medical and Dental Sciences, Bunkyo-ku, Tokyo, Japan
- Center for Brain Integration Research, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan
| |
Collapse
|