The following are brief descriptions of the CNS glial cell types:. Astrocytes: these cells have numerous projections and anchor neurons to their blood supply.
They also regulate the local environment by removing excess ions and recycling neurotransmitters. Oligodendrocytes: responsible for creating the myelin sheath — this thin layer coats nerve cells, allowing them to send signals quickly and efficiently. Ependymal cells: lining the spinal cord and the brain's ventricles fluid-filled spaces , these create and secrete cerebrospinal fluid CSF and keep it circulating using their whip-like cilia.
Radial glia: act as scaffolding for new nerve cells during the creation of the embryo's nervous system. The cranial nerves are 12 pairs of nerves that arise directly from the brain and pass through holes in the skull rather than traveling along the spinal cord. These nerves collect and send information between the brain and parts of the body — mostly the neck and head.
Of these 12 pairs, the olfactory and optic nerves arise from the forebrain and are considered part of the central nervous system:. Olfactory nerves cranial nerve I : transmit information about odors from the upper section of the nasal cavity to the olfactory bulbs on the base of the brain. Optic nerves cranial nerve II : carry visual information from the retina to the primary visual nuclei of the brain. Each optic nerve consists of around 1. Trauma: depending on the site of the injury, symptoms can vary widely from paralysis to mood disorders. Infections: some micro-organisms and viruses can invade the CNS; these include fungi, such as cryptococcal meningitis; protozoa, including malaria; bacteria, as is the case with leprosy, or viruses.
Degeneration: in some cases, the spinal cord or brain can degenerate. One example is Parkinson's disease which involves the gradual degeneration of dopamine-producing cells in the basal ganglia. Structural defects: the most common examples are birth defects; including anencephaly, where parts of the skull, brain, and scalp are missing at birth. Tumors: both cancerous and noncancerous tumors can impact parts of the central nervous system.
Both types can cause damage and yield an array of symptoms depending on where they develop. Autoimmune disorders: in some cases, an individual's immune system can mount an attack on healthy cells. For instance, acute disseminated encephalomyelitis is characterized by an immune response against the brain and spinal cord, attacking myelin the nerves' insulation and, therefore, destroying white matter. Stroke: a stroke is an interruption of blood supply to the brain; the resulting lack of oxygen causes tissue to die in the affected area.
The term peripheral nervous system PNS refers to any part of the nervous system that lies outside of the brain and spinal cord. The CNS is separate from the peripheral nervous system, although the two systems are interconnected. The nerve axons of the CNS — the slender projections of nerve cells that carry impulses — are much shorter. PNS nerve axons can be up to 1 meter long for instance, the nerve that activates the big toe whereas, within the CNS, they are rarely longer than a few millimeters.
Much of the PNS has the ability to regenerate; if a nerve in your finger is severed, it can regrow. The CNS, however, does not have this ability. The components of the central nervous system are further split into a myriad of parts. Below, we will describe some of these sections in a little more detail. Article last updated by Tim Newman on Fri 22 December All references are available in the References tab. Cantalupo, C. Asymmetric Broca's area in great apes: A region of the ape brain is uncannily similar to one linked with speech in humans.
Driesen, N. The influence of sex, age, and handedness on corpus callosum morphology: A meta-analysis. Herculano-Houzel, S. The human brain in numbers: a linearly scaled-up primate brain. Vilensky, J. The neglected cranial nerve: nervus terminalis cranial nerve N. MLA Newman, Tim. MediLexicon, Intl. APA Newman, T. MNT is the registered trade mark of Healthline Media.
Scroll to Accept. Get the MNT newsletter. The examiner also looks for atrophy or tremor of the tongue. The strength of the tongue is tested by asking the patient to protrude it and to move it from side to side against a tongue depressor Figure 3. The functions of these fiber bundles are considered in later course sessions. For now, it is sufficient to learn the difference between the cerebral and cerebellar peduncles and their locations in the brainstem.
You have already been introduced to these peduncles; now use Figure 2. The internal organization of the brainstem is considerably more complicated than that of the spinal cord. However, two factors work in your favor as you study its features. First, important general principles of organization of the spinal cord also hold true for the brainstem. Second, much of the complexity of the brainstem is contributed by cell groups and axon tracts that will not be considered in this course. In the following discussion, the general plan of organization of the brainstem is presented first.
Next, the prominent internal features that characterize each subdivision are identified. An understanding of the functions and locations of these nuclei is essential for diagnosing and treating neurological injury, dysfunction and disease, as well as mental illness and a spectrum of dysfunctions manifest in human behavior. However, the brainstem changes continuously along its length—the subdivision into three parts is somewhat arbitrary.
As a compromise between examining three sections one for each subdivision and hundreds, seven sections of the brainstem are shown to serve as representatives Figure 2. Once you understand the organization of these seven levels and the way various pathways traverse them, you should be able to identify the location of any section through the brainstem and the important pathways represented in it.
A schematic overview of the levels of the brainstem to be discussed is presented in Figure 4. At this stage, it is not important to study the details; we will come back to them. For now, three points should be taken from the figure:. In Figures 2. As usual, be sure to focus on the structures identified in the figure legends in bold font.
Our purpose here is to help you recognize the distinctive features of the embryological subdivisions of the brainstem, and to introduce you to some of the gray matter nuclei and white matter tracts; peduncles that you will study in more detail elsewhere in the course. We will return to these same sections frequently as the course progress these same section are fully annotated in Sylvius4 Online , including the next laboratory session when we will turn our attention squarely on the cranial nerve and neuromodulatory nuclei.
The Brainstem Cross Sectional Atlas in Sylvius4 contains 14 sections through the brainstem and four spinal cord sections featuring segmentation of well over neuroanatomical structures. This atlas should be used to fill-in the gaps between the seven sections illustrated in this chapter. As you work through these chapter figures and the associated legends, find the same structures one at a time in the Brainstem Cross Sectional Atlas in Sylvius4. The sections shown here are actually re-colorized versions of the same sections that are in Sylvius4. Since we are not yet studying the functional significance of many of these structures we will do so over the next few weeks , you should click on the structures identified in the figures, and when you do so, that structure becomes selected and a brief overview of that structure becomes available in the text window.
Tip —to increase the magnification of the image, grab the lower-right corner of the image window and pull the window to its maximum extent. With reference to Figures 2. Spend some time browsing the six medullary sections in Sylvius4 , and find each of the internal features described in the chart below.
Surface feature. Internal structure. Caudal medulla Figure 2. Gracile tract dorsal surface. Cuneate tract dorsal surface. Pyramidal decussation ventral surface. Middle to rostral medulla Figure 2. Medullary pyramids ventral surface. Inferior olive ventral-lateral surface.
Hypoglossal nerve XII ventral-lateral surface. As you did for the medulla, spend some time browsing the sections in Sylvius4 , and find each of the internal features described in the chart below. Middle of pons fig 2. Middle cerebellar peduncle ventral-lateral surface. Trigeminal nerve V ventral-lateral surface. Caudal pons fig 2. Abducens nerve VI ventral-medial surface. Facial nerve VII ventral-lateral surface. Vestibulocochlear nerve VIII ventral-lateral surface.
As you did for the medulla and pons, now spend some time browsing the sections in Sylvius4 , and find each of the internal features described in the chart below. Midbrain Figures 2. Cerebral peduncles ventral surface. Oculomotor nerve III ventral surface. Inferior colliculi dorsal surface. Superior colliculi dorsal surface. Examine slabs through human brainstem specimens. Click here to submit questions or comments about this site. Course Information. Contact Faculty. Head Cross Sections.
Anatomy Site. Histology Site. Embryology Site. Mnemonic note: the nerves with a roman numeral X in their name enter and exit at the medulla , those with a "V" except IV enter and exit the pons. Ventral surface of midbrain. Laboratory Guide, Chapter 3. Lab 3 Protocols Spinal Cord Learning objective : to recognize the principal features of the spinal cord, including the longitudinal organization of spinal segments and internal distinctions among levels.
Specimens: one spinal cord specimen available for demonstration purposes Activities: Open the Laboratory Guide to Figure 2. Identify the cervical and lumbosacral enlargements, and the thoracic and sacral regions. Identify dorsal and ventral roots. Differentiate the dura mater from arachnoid mater, and identify denticulate ligaments Identify the posterior and anterior spinal arteries, and draining veins Open the Laboratory Guide to Figure 2.
Do Challenge 3. Medulla oblongata Learning objective : to recognize the principal features of the medulla oblongata as seen from the surface, including the attachments of cranial nerves VI-X and XII and XI. Specimens : whole brains, mid-sagittal hemispheres, and brain or brainstem models Activities : Refer to Figure 2. Find each of the features listed in the chart and described in the text as you can on actual specimens of the human brainstem.
Some features may be best observed in whole brain specimens, but some may be appreciated just as easily in hemi-brains that were sectioned in the mid-sagittal plane.
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Pons Learning objective : to recognize the principal features of the pons as seen from the surface, including the attachments of cranial nerves V and VI-VIII. Some features may be best observed in whole brain specimens, but some may be appreciated best in hemi-brains that were sectioned in the mid-sagittal plane.
Do the brainstem Challenges Learning objective : to recognize the relation between major external features of the brainstem, including the cranial nerves, and internal gray matter and white matter structures in each embryological division. Find each of the features listed in the charts and described in the text as you can on actual specimens. Identify internal features of the brainstem that account for distinctive external features of each embryological subdivision; refer to the Brainstem Atlas in Sylvius4 Online for additional sections and annotations.
Examine slabs through human brainstem specimens Learning objective : to recognize the principal features of the brainstem that are visible with the unaided eye, including major gray matter and white matter structures in each embryological division. Specimens: whole brain slabs or gross sections cut through the brainstem Activities: Repeat Challenges 2.
Find as many of the visible gray and white matter features listed in the chart and described in the text as you can on actual specimens of the human brainstem. Introduction The central nervous system interacts with the outside world through primary sensory neurons, which convey information from the body or its environment into the brain and spinal cord, and motor neurons, which activate striated muscles and modulate the activity of cardiac and smooth muscles and glands Figure 2.
Terminology and general principles The next few sections contain definitions and illustrations of some commonly used neuroanatomical terminology. Terms used to refer to gray matter Column Cortex plural: cortices; L. You will also encounter the following terms used to refer to general regions of the central nervous system: tectum L. The spinal cord Learning objective : to recognize the principal features of the spinal cord, including the longitudinal organization of spinal segments and internal distinctions among levels.
Specimens : one spinal cord specimen available for demonstration purposes Activities : Open the Laboratory Guide to Figure 2. Do Challenge 2. Internal anatomy of the spinal cord The following discussion of the internal anatomy of the spinal cord will introduce some of the general principles of organization that also hold true for the brainstem.
Challenge 3. Chart Dorsal horn. Lateral horn. Ventral horn. White matter. Gracile tract. Cuneate tract. Sylvius Self-Study Exercise—Medullary surface click here to launch Sylvius online To explore the surface of the medulla when the brain is not in hand, open Sylvius4 , enter the Brainstem Model in the Surface Anatomy group, and select Brainstem Model. Sylvius Self-Study Exercise—Pontine surface click here to launch Sylvius online To explore the surface of the pons when the brain is not in hand, open Sylvius4 , enter the Brainstem Model in the Surface Anatomy group, and select Brainstem Model.
So the trochlear nerve is unsual in these two respects: 1 it exits the CNS from the dorsal aspect; and 2 it supplies contralateral muscles. Sylvius Self-Study Exercise—Midbrain surface click here to launch Sylvius online To explore the surface of the midbrain when the brain is not in hand, open Sylvius4 , enter the Brainstem Model in the Surface Anatomy group, and select Brainstem Model. Sylvius Self-Study Exercise—Internal Brainstem Features click here to launch Sylvius online The Brainstem Cross Sectional Atlas in Sylvius4 contains 14 sections through the brainstem and four spinal cord sections featuring segmentation of well over neuroanatomical structures.
Challenge 2. Gracile tract dorsal surface pair of extended longitudinal bulges on either side of a deep midline furrow; technically, this bulge is called the tuberculum gracilis , which is formed by the underlying gracile tract continuation of the tract of the dorsal spinal cord. Cuneate tract dorsal surface pair of extended longitudinal bulges just lateral to the gracile tracts; technically, this bulge is called the tuberculum cuneatus , which is formed by the underlying cuneate tract continuation of the tract of the dorsal spinal cord.
Pyramidal decussation see Medullary pyramids below midline crossing of dense bundles of myelinated axons that run the longitudinal extent of the ventral brainstem accounts for the formation of the lateral and ventral anterior corticospinal tracts of the spinal cord. Medullary pyramids ventral surface pair of extended longitudinal bulges on either side of a deep midline furrow. Inferior olive ventral-lateral surface pair of elongated bulges just lateral to the pyramids; a shallow furrow separates the pyramid and olive on each side. Inferior olivary nucleus prominent nucleus of the ventral-lateral medulla just dorsal to the medullary pyramids note the highly convoluted bands of gray matter that account for the superficial, ventral-lateral bulge.
Hypoglossal nerve XII ventral-lateral surface exits through ventral-medial surface. Vestibulocochlear nerve VIII ventral-lateral surface enters through ventral-lateral surface at pontomedullary junction most lateral of the three that emerge from this junction. Vestibular nuclear complex explore the lateral tegmentum of the pons and locate nuclei of the vestibular nuclear complex you may not find any nerve VIII roots in these cross sections ; you will find the vestibular nuclei dorsal to the trigeminal nuclear complex and spinal trigeminal tract find the superior, lateral and medial vestibular nuclei section down into the medulla and locate the spinal vestibular nucleus so what about the cochlear division of nerve VIII?
It terminates in a superficial nucleus of the dorsal-lateral upper medulla called the cochlear nucleus. Hamburger, V. Cell death in the development of the lateral motor column of the chick embryo. History of the discovery of neuronal death in embryos. Hammerle, B. Helmbacher, F. Met signaling is required for recruitment of motor neurons to PEA3-positive motor pools.
Neuron 39, — Henderson, C. Role of neurotrophic factors in neuronal development. GDNF: a potent survival factor for motoneurons present in peripheral nerve and muscle. Hirsch, M. Forced expression of Phox2 homeodomain transcription factors induces a branchio-visceromotor axonal phenotype. Hollyday, M. An autoradiographic study of the formation of the lateral motor column in the chick embryo. Localization of motor neuron pools supplying identified muscles in normal and supernumerary legs of chick embryo. Location of motor pools innervating chick wing. Huber, A. Distinct roles for secreted semaphorin signaling in spinal motor axon guidance.
Neuron 48, — Huettl, R. Npn-1 contributes to axon-axon interactions that differentially control sensory and motor innervation of the limb. Iulianella, A. Cux2 Cutl2 integrates neural progenitor development with cell-cycle progression during spinal cord neurogenesis. Ivanhoe, C. Spasticity: the misunderstood part of the upper motor neuron syndrome. Jacobson, M. Developmental Neurobiology. Google Scholar. Jacobson, S. Neuroanatomy for the Neuroscientist. Jessell, T. Neuronal specification in the spinal cord: inductive signals and transcriptional codes.
Jung, H. Global control of motor neuron topography mediated by the repressive actions of a single hox gene. Neuron 67, — Evolving hox activity profiles govern diversity in locomotor systems. Cell 29, — Kania, A. Concocting cholinergy. Spinal motor neuron migration and the significance of topographic organization in the nervous system. Topographic motor projections in the limb imposed by LIM homeodomain protein regulation of ephrin-A:EphA interactions.
Neuron 38, — Coordinate roles for LIM homeobox genes in directing the dorsoventral trajectory of motor axons in the vertebrate limb. Kanning, K. Motor neuron diversity in development and disease. Kao, T. Ephrin-mediated cis-attenuation of Eph receptor signaling is essential for spinal motor axon guidance.
Neuron 71, 76— Eph and ephrin signaling: lessons learned from spinal motor neurons. Cell Dev. Kessel, M. Homeotic transformations of murine vertebrae and concomitant alteration of Hox codes induced by retinoic acid. Cell 67, 89— Kobayashi, N. Elucidation of target muscle and detailed development of dorsal motor neurons in chick embryo spinal cord.
Kramer, E. Neuron 50, 35— Lacombe, J. Genetic and functional modularity of Hox activities in the specification of limb-innervating motor neurons. Ladle, D. Assembly of motor circuits in the spinal cord: driven to function by genetic and experience-dependent mechanisms. Neuron 56, — Lamballe, F. Pool-specific regulation of motor neuron survival by neurotrophic support. Lance-Jones, C. Motoneurone projection patterns in the chick hind limb following early partial reversals of the spinal cord.
Hoxd10 induction and regionalization in the developing lumbosacral spinal cord.
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Landmesser, L. The distribution of motoneurones supplying chick hind limb muscles. The acquisition of motoneuron subtype identity and motor circuit formation. Laumonnerie, C. Netrin 1 and Dcc signalling are required for confinement of central axons within the central nervous system.
Lee, R. Bistability in spinal motoneurons in vivo : systematic variations in persistent inward currents. Lee, S. Analysis of embryonic motoneuron gene regulation: derepression of general activators function in concert with enhancer factors. Olig2 and Ngn2 function in opposition to modulate gene expression in motor neuron progenitor cells. Synchronization of neurogenesis and motor neuron specification by direct coupling of bHLH and homeodomain transcription factors. A regulatory network to segregate the identity of neuronal subtypes.
Cell 14, — Retinoid signaling and neurogenin2 function are coupled for the specification of spinal motor neurons through a chromatin modifier CBP. Neuron 62, — Lei, Q. Wnt signaling inhibitors regulate the transcriptional response to morphogenetic Shh-Gli signaling in the neural tube. Cell 11, — Li, M. Essential function of LIF receptor in motor neurons. Lieberam, I. Neuron 47, — Lin, J. Functionally related motor neuron pool and muscle sensory afferent subtypes defined by coordinate ETS gene expression. Cell 95, — Liu, J. Assigning the positional identity of spinal motor neurons: rostrocaudal patterning of Hox-c expression by FGFs, Gdf11, and retinoids.
Neuron 32, — Livet, J. ETS gene Pea3 controls the central position and terminal arborization of specific motor neuron pools. Lu, Q. Cell , 75— Luria, V. Specification of motor axon trajectory by ephrin-B:EphB signaling: symmetrical control of axonal patterning in the developing limb.
Neuron 60, — Machado, C. Reconstruction of phrenic neuron identity in embryonic stem cell-derived motor neurons. Maier, A. Development and regeneration of muscle spindles in mammals and birds. Marti, E. Requirement of 19K form of Sonic hedgehog for induction of distinct ventral cell types in CNS explants. Distribution of Sonic hedgehog peptides in the developing chick and mouse embryo. Mazzoni, E. Synergistic binding of transcription factors to cell-specific enhancers programs motor neuron identity.
Saltatory remodeling of Hox chromatin in response to rostrocaudal patterning signals. Mehler, M. Bone morphogenetic proteins in the nervous system. Trends Neurosci. Mizuguchi, R. Combinatorial roles of olig2 and neurogenin2 in the coordinated induction of pan-neuronal and subtype-specific properties of motoneurons. Neuron 31, — Morikawa, Y. Detailed expression pattern of Foxp1 and its possible roles in neurons of the spinal cord during embryogenesis.
Muhr, J. Convergent inductive signals specify midbrain, hindbrain, and spinal cord identity in gastrula stage chick embryos. Muller, D. Dlk1 promotes a fast motor neuron biophysical signature required for peak force execution. Niederreither, K. Restricted expression and retinoic acid-induced downregulation of the retinaldehyde dehydrogenase type 2 RALDH-2 gene during mouse development.
Niewiadomski, P. Gli protein activity is controlled by multisite phosphorylation in vertebrate hedgehog signaling. Nornes, H. Neurogenesis in spinal cord of mouse: an autoradiographic analysis. Novitch, B. Coordinate regulation of motor neuron subtype identity and pan-neuronal properties by the bHLH repressor Olig2.
A requirement for retinoic acid-mediated transcriptional activation in ventral neural patterning and motor neuron specification. Neuron 40, 81— Oppenheim, R. The absence of significant postnatal motoneuron death in the brachial and lumbar spinal cord of the rat. Cell death during development of the nervous system. Neurotrophic survival molecules for motoneurons: an embarrassment of riches. Neuron 17, — Developing motor neurons rescued from programmed and axotomy-induced cell death by GDNF. Glial cell line-derived neurotrophic factor and developing mammalian motoneurons: regulation of programmed cell death among motoneuron subtypes.
Otaegi, G. An optimized sponge for microrNA miR-9 affects spinal motor neuron development in vivo. Pabst, O. Nkx is a novel homeobox transcription factor which demarcates ventral domains in the developing mouse CNS. Targeted disruption of the homeobox gene Nkx2. Palmesino, E. Foxp1 and lhx1 coordinate motor neuron migration with axon trajectory choice by gating reelin signalling. Park, S. Pattyn, A. Control of hindbrain motor neuron differentiation by the homeobox gene Phox2b. Periz, G. Pettmann, B.
Neuronal cell death. Neuron 20, — CrossRef Full Text. Pfaff, S. Developmental neuroscience: hox and fox. Phelan, K. Axon guidance in muscleless chick wings: the role of muscle cells in motoneuronal pathway selection and muscle nerve formation. Philippidou, P. Hox genes: choreographers in neural development, architects of circuit organization.
Neuron 80, 12— Sustained Hox5 gene activity is required for respiratory motor neuron development. Pierani, A. A sonic hedgehog-independent, retinoid-activated pathway of neurogenesis in the ventral spinal cord. Cell 97, — Poulsen, K. Neuron 13, — Prakash, Y. Phrenic motoneuron morphology during rapid diaphragm muscle growth. Prasad, A. Development and migration of avian sympathetic preganglionic neurons. Purves, D. Sunderland, MA: Sinauer Associates. Quirk, J. The smoothened gene and hedgehog signal transduction in Drosophila and vertebrate development.
Rafuse, V. Selective innervation of fast and slow muscle regions during early chick neuromuscular development. Rao, M. Transmembrane protein GDE2 induces motor neuron differentiation in vivo. Rexed, B. A cytoarchitectonic atlas of the spinal cord in the cat.
Richardson, W. Oligodendrocyte lineage and the motor neuron connection. Glia 29, — Roelink, H. Floor plate and motor neuron induction by vhh-1, a vertebrate homolog of hedgehog expressed by the notochord. Cell 76, — Romanes, G. The development and significance of the cell columns in the ventral horn of the cervical and upper thoracic spinal cord of the rabbit. Rousso, D. Coordinated actions of the forkhead protein Foxp1 and Hox proteins in the columnar organization of spinal motor neurons.
Neuron 59, — Foxp-mediated suppression of N-cadherin regulates neuroepithelial character and progenitor maintenance in the CNS. Neuron 74, — Roy, A. Onecut transcription factors act upstream of Isl1 to regulate spinal motoneuron diversification. Ryan, J. Topographic position of forelimb motoneuron pools is conserved in vertebrate evolution.
Brain Behav. Sabharwal, P. GDE2 regulates subtype-specific motor neuron generation through inhibition of Notch signaling. Neuron 71, — Saito, S. Rat spinal cord neurons contain nitric oxide synthase.
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Neuroscience 59, — Scardigli, R. Crossregulation between Neurogenin2 and pathways specifying neuronal identity in the spinal cord. Schubert, W. Identification and characterization of a cell surface marker for embryonic rat spinal accessory motor neurons. Shah, V. Ectopic expression of Hoxd10 in thoracic spinal segments induces motoneurons with a lumbosacral molecular profile and axon projections to the limb. Sharma, K.
Genetic and epigenetic mechanisms contribute to motor neuron pathfinding. LIM homeodomain factors Lhx3 and Lhx4 assign subtype identities for motor neurons. Shirasaki, R. FGF as a target-derived chemoattractant for developing motor axons genetically programmed by the LIM code.
Neuron 50, — Transcriptional codes and the control of neuronal identity. Shneider, N. Gamma motor neurons express distinct genetic markers at birth and require muscle spindle-derived GDNF for postnatal survival. Neural Dev. Smith, C. The development and postnatal organization of motor nuclei in the rat thoracic spinal cord. Snider, W. Functions of the neurotrophins during nervous system development: what the knockouts are teaching us.
Cell 77, — Sockanathan, S. Motor neuron-derived retinoid signaling specifies the subtype identity of spinal motor neurons. Cell 94, — Retinoid receptor signaling in postmitotic motor neurons regulates rostrocaudal positional identity and axonal projection pattern. Neuron 40, 97— Sommer, L. Song, A. Development of the rat phrenic nucleus and its connections with brainstem respiratory nuclei. Song, M. Islet-to-LMO stoichiometries control the function of transcription complexes that specify motor neuron and V2a interneuron identity.
Soundararajan, P. Stepien, A. Monosynaptic rabies virus reveals premotor network organization and synaptic specificity of cholinergic partition cells. Neuron 68, — Stifani, N. Stifani, S. Blood Cells Mol. Stone, D. The tumour-suppressor gene patched encodes a candidate receptor for Sonic hedgehog. Stone, R. Atlas of Skeletal Muscles. Straznicky, C. The localization of motoneuron pools innervating wing muscles in the chick. Streit, A. Chordin regulates primitive streak development and the stability of induced neural cells, but is not sufficient for neural induction in the chick embryo.
Sullivan, G. Anatomy and embryology of the wing musculature of the domestic fowl gallus.
Tanabe, Y. Specification of motor neuron identity by the MNR2 homeodomain protein. Cell 95, 67— Thaler, J. Active suppression of interneuron programs within developing motor neurons revealed by analysis of homeodomain factor HB9. A postmitotic role for Isl-class LIM homeodomain proteins in the assignment of visceral spinal motor neuron identity.
Neuron 41, — LIM factor Lhx3 contributes to the specification of motor neuron and interneuron identity through cell-type-specific protein-protein interactions. Theriault, F. Todd, K. Establishment of motor neuron-V3 interneuron progenitor domain boundary in ventral spinal cord requires Groucho-mediated transcriptional corepression. Tosney, K. Specifying the target identity of motoneurons. BioEssays 17, — Development of the major pathways for neurite outgrowth in the chick hindlimb. Specificity of early motoneuron growth cone outgrowth in the chick embryo.
Tripodi, M. Motor antagonism exposed by spatial segregation and timing of neurogenesis. Nature , 61— Tsuchida, T. Topographic organization of embryonic motor neurons defined by expression of LIM homeobox genes. Cell 79, — Ullah, M. Localization of the spinal nucleus of accessory nerve in rat: a horseradish peroxidase study. Ulloa, F. Wnt won the war: antagonistic role of Wnt over Shh controls dorso-ventral patterning of the vertebrate neural tube.
Developmental Dyn. Vallstedt, A. Different levels of repressor activity assign redundant and specific roles to Nkx6 genes in motor neuron and interneuron specification. Vermot, J. Visvanathan, J. Vrieseling, E. Target-induced transcriptional control of dendritic patterning and connectivity in motor neurons by the ETS gene Pea3. Wang, G. Wang, L. Anatomical coupling of sensory and motor nerve trajectory via axon tracking. Watanabe, T.
Location of motoneurons supplying upper neck muscles in the chicken studied by means of horseradish peroxidase. Webber, C. Structural and functional characteristics of individual phrenic motoneurons. Pflugers Arch. Westbury, D.