|A personal message from Dr Mark Hill (May 2020)
| I have decided to take early retirement in September 2020. During the many years online I have received wonderful feedback from many readers, researchers and students interested in human embryology. I especially thank my research collaborators and contributors to the site. The good news is Embryology will remain online and I will continue my association with UNSW Australia. I look forward to updating and including the many exciting new discoveries in Embryology!
The prosemeric (neuromeric) model describes brain development based upon a series of neural tube transverse subunits (segmental) and integrates with the longitudinal (columnar) concepts. Historically described as primary and secondary vesicles, the modern interpretation of segmentation is based upon regional gene expression. Best example that corresponds to morphological features is found in the hindbrain rhombomeric HOX expression pattern.
Review - Time for Radical Changes in Brain Stem Nomenclature-Applying the Lessons From Developmental Gene Patterns "The traditional subdivision of the brain stem into midbrain, pons, and medulla oblongata is based purely on the external appearance of the human brain stem. There is an urgent need to update the names of brain stem structures to be consistent with the discovery of rhomobomeric segmentation based on gene expression. The most important mistakes are the belief that the pons occupies the upper half of the hindbrain, the failure to recognize the isthmus as the first segment of the hindbrain, and the mistaken inclusion of diencephalic structures in the midbrain. The new nomenclature will apply to all mammals. This essay recommends a new brain stem nomenclature based on developmental gene expression, progeny analysis, and fate mapping."
Some Recent Findings
- Developmental studies of avian brain organization "Avian brain organization or brain Bauplan is identical with that of vertebrates in general. This essay visits avian studies that contained advances or discussions about brain organization, trying to explain critically what they contributed. In order to start from a specific background, the new prevailing paradigm as regards brain organization, the prosomeric model, is presented first. Next a brief historic survey is made of how ideas on this topic evolved from the start of modern neuromorphology at the end of the 19th century. Longitudinal zonal organization with or without transverse segmentation (neuromeres) was the first overall concept applied to the brain. The idea of neuromeric structure later decayed in favour of a columnar model. This emphasized functional correlations rather than causal developmental content, assimilating forebrain functions to hindbrain ones. Though it became prevalent in the post-world-war period of neuroscience, in the last decades of the 20th century advances in molecular biology allowed developmental genes to be mapped, and it became evident that gene expression patterns support the old neuromeric model rather than the columnar one. This was also corroborated by modern experimental approaches (fate-mapping and analysis of patterning). chicken
- Review - Evolution of the Human Nervous System Function, Structure, and Development "The nervous system-in particular, the brain and its cognitive abilities-is among humans' most distinctive and impressive attributes. How the nervous system has changed in the human lineage and how it differs from that of closely related primates is not well understood. Here, we consider recent comparative analyses of extant species that are uncovering new evidence for evolutionary changes in the size and the number of neurons in the human nervous system, as well as the cellular and molecular reorganization of its neural circuits. We also discuss the developmental mechanisms and underlying genetic and molecular changes that generate these structural and functional differences."
|More recent papers
This table allows an automated computer search of the external PubMed database using the listed "Search term" text link.
- This search now requires a manual link as the original PubMed extension has been disabled.
- The displayed list of references do not reflect any editorial selection of material based on content or relevance.
- References also appear on this list based upon the date of the actual page viewing.
References listed on the rest of the content page and the associated discussion page (listed under the publication year sub-headings) do include some editorial selection based upon both relevance and availability.
More? References | Discussion Page | Journal Searches | 2019 References | 2020 References
Search term: Prosomere | Prosomeres | prosemeric model | neuromeric model
|These papers originally appeared in the Some Recent Findings table, but as that list grew in length have now been shuffled down to this collapsible table.
See also the Discussion Page for other references listed by year and References on this current page.
- ↑ Watson C, Bartholomaeus C & Puelles L. (2019). Time for Radical Changes in Brain Stem Nomenclature-Applying the Lessons From Developmental Gene Patterns. Front Neuroanat , 13, 10. PMID: 30809133 DOI.
- ↑ Puelles L. (2018). Developmental studies of avian brain organization. Int. J. Dev. Biol. , 62, 207-224. PMID: 29616730 DOI.
- ↑ Sousa AMM, Meyer KA, Santpere G, Gulden FO & Sestan N. (2017). Evolution of the Human Nervous System Function, Structure, and Development. Cell , 170, 226-247. PMID: 28708995 DOI.
Whalley K. (2017). Gene expression: Evolving expression patterns. Nat. Rev. Neurosci. , 19, 7. PMID: 29238089 DOI.
Alvarez-Bolado G, Grinevich V & Puelles L. (2015). Editorial: Development of the hypothalamus. Front Neuroanat , 9, 83. PMID: 26157363 DOI.
Ferran JL, Puelles L & Rubenstein JL. (2015). Molecular codes defining rostrocaudal domains in the embryonic mouse hypothalamus. Front Neuroanat , 9, 46. PMID: 25941476 DOI.
Santos-Durán GN, Menuet A, Lagadec R, Mayeur H, Ferreiro-Galve S, Mazan S, Rodríguez-Moldes I & Candal E. (2015). Prosomeric organization of the hypothalamus in an elasmobranch, the catshark Scyliorhinus canicula. Front Neuroanat , 9, 37. PMID: 25904850 DOI.
Puelles L & Rubenstein JL. (2015). A new scenario of hypothalamic organization: rationale of new hypotheses introduced in the updated prosomeric model. Front Neuroanat , 9, 27. PMID: 25852489 DOI.
Cajal M, Creuzet SE, Papanayotou C, Sabéran-Djoneidi D, Chuva de Sousa Lopes SM, Zwijsen A, Collignon J & Camus A. (2014). A conserved role for non-neural ectoderm cells in early neural development. Development , 141, 4127-38. PMID: 25273086 DOI.
Domínguez L, González A & Moreno N. (2014). Characterization of the hypothalamus of Xenopus laevis during development. II. The basal regions. J. Comp. Neurol. , 522, 1102-31. PMID: 24122702 DOI.
Lauter G, Söll I & Hauptmann G. (2013). Molecular characterization of prosomeric and intraprosomeric subdivisions of the embryonic zebrafish diencephalon. J. Comp. Neurol. , 521, 1093-118. PMID: 22949352 DOI.
Domínguez L, Morona R, González A & Moreno N. (2013). Characterization of the hypothalamus of Xenopus laevis during development. I. The alar regions. J. Comp. Neurol. , 521, 725-59. PMID: 22965483 DOI.
Beccari L, Marco-Ferreres R & Bovolenta P. (2013). The logic of gene regulatory networks in early vertebrate forebrain patterning. Mech. Dev. , 130, 95-111. PMID: 23111324 DOI.
Rash BG & Grove EA. (2011). Shh and Gli3 regulate formation of the telencephalic-diencephalic junction and suppress an isthmus-like signaling source in the forebrain. Dev. Biol. , 359, 242-50. PMID: 21925158 DOI.
Villar-Cerviño V, Barreiro-Iglesias A, Mazan S, Rodicio MC & Anadón R. (2011). Glutamatergic neuronal populations in the forebrain of the sea lamprey, Petromyzon marinus: an in situ hybridization and immunocytochemical study. J. Comp. Neurol. , 519, 1712-35. PMID: 21452205 DOI.
Martínez-de-la-Torre M, Pombal MA & Puelles L. (2011). Distal-less-like protein distribution in the larval lamprey forebrain. Neuroscience , 178, 270-84. PMID: 21185911 DOI.
Moreno N & González A. (2011). The non-evaginated secondary prosencephalon of vertebrates. Front Neuroanat , 5, 12. PMID: 21427782 DOI.
Domínguez L, González A & Moreno N. (2011). Ontogenetic distribution of the transcription factor nkx2.2 in the developing forebrain of Xenopus laevis. Front Neuroanat , 5, 11. PMID: 21415915 DOI.
Sugahara F, Aota S, Kuraku S, Murakami Y, Takio-Ogawa Y, Hirano S & Kuratani S. (2011). Involvement of Hedgehog and FGF signalling in the lamprey telencephalon: evolution of regionalization and dorsoventral patterning of the vertebrate forebrain. Development , 138, 1217-26. PMID: 21343370 DOI.
Yamamoto K, Ruuskanen JO, Wullimann MF & Vernier P. (2011). Differential expression of dopaminergic cell markers in the adult zebrafish forebrain. J. Comp. Neurol. , 519, 576-98. PMID: 21192085 DOI.
Suda Y, Kokura K, Kimura J, Kajikawa E, Inoue F & Aizawa S. (2010). The same enhancer regulates the earliest Emx2 expression in caudal forebrain primordium, subsequent expression in dorsal telencephalon and later expression in the cortical ventricular zone. Development , 137, 2939-49. PMID: 20667915 DOI.
Garcia-Lopez R & Martinez S. (2010). Oligodendrocyte precursors originate in the parabasal band of the basal plate in prosomere 1 and migrate into the alar prosencephalon during chick development. Glia , 58, 1437-50. PMID: 20648637 DOI.
Abellán A, Vernier B, Rétaux S & Medina L. (2010). Similarities and differences in the forebrain expression of Lhx1 and Lhx5 between chicken and mouse: Insights for understanding telencephalic development and evolution. J. Comp. Neurol. , 518, 3512-28. PMID: 20589911 DOI.
Osório J, Mueller T, Rétaux S, Vernier P & Wullimann MF. (2010). Phylotypic expression of the bHLH genes Neurogenin2, Neurod, and Mash1 in the mouse embryonic forebrain. J. Comp. Neurol. , 518, 851-71. PMID: 20058311 DOI.
Pritz MB. (2010). Forebrain and midbrain fiber tract formation during early development in Alligator embryos. Brain Res. , 1313, 34-44. PMID: 19968970 DOI.
García-López R, Soula C & Martínez S. (2009). Expression analysis of Sulf1 in the chick forebrain at early and late stages of development. Dev. Dyn. , 238, 2418-29. PMID: 19653319 DOI.
Hoch RV, Rubenstein JL & Pleasure S. (2009). Genes and signaling events that establish regional patterning of the mammalian forebrain. Semin. Cell Dev. Biol. , 20, 378-86. PMID: 19560042 DOI.
Quinn JC, Molinek M, Mason JO & Price DJ. (2009). Gli3 is required autonomously for dorsal telencephalic cells to adopt appropriate fates during embryonic forebrain development. Dev. Biol. , 327, 204-15. PMID: 19121302 DOI.
Mueller T & Wullimann MF. (2009). An evolutionary interpretation of teleostean forebrain anatomy. Brain Behav. Evol. , 74, 30-42. PMID: 19729894 DOI.
Pombal MA, Megías M, Bardet SM & Puelles L. (2009). New and old thoughts on the segmental organization of the forebrain in lampreys. Brain Behav. Evol. , 74, 7-19. PMID: 19729892 DOI.
Morona R & González A. (2008). Calbindin-D28k and calretinin expression in the forebrain of anuran and urodele amphibians: further support for newly identified subdivisions. J. Comp. Neurol. , 511, 187-220. PMID: 18781620 DOI.
Takahashi K, Liu FC, Hirokawa K & Takahashi H. (2008). Expression of Foxp4 in the developing and adult rat forebrain. J. Neurosci. Res. , 86, 3106-16. PMID: 18561326 DOI.
van den Akker WM, Brox A, Puelles L, Durston AJ & Medina L. (2008). Comparative functional analysis provides evidence for a crucial role for the homeobox gene Nkx2.1/Titf-1 in forebrain evolution. J. Comp. Neurol. , 506, 211-23. PMID: 18022953 DOI.
Poitras L, Ghanem N, Hatch G & Ekker M. (2007). The proneural determinant MASH1 regulates forebrain Dlx1/2 expression through the I12b intergenic enhancer. Development , 134, 1755-65. PMID: 17409112 DOI.
Menuet A, Alunni A, Joly JS, Jeffery WR & Rétaux S. (2007). Expanded expression of Sonic Hedgehog in Astyanax cavefish: multiple consequences on forebrain development and evolution. Development , 134, 845-55. PMID: 17251267 DOI.
Kitambi SS & Hauptmann G. (2007). The zebrafish orphan nuclear receptor genes nr2e1 and nr2e3 are expressed in developing eye and forebrain. Gene Expr. Patterns , 7, 521-8. PMID: 17127102 DOI.
Jeong JY, Einhorn Z, Mathur P, Chen L, Lee S, Kawakami K & Guo S. (2007). Patterning the zebrafish diencephalon by the conserved zinc-finger protein Fezl. Development , 134, 127-36. PMID: 17164418 DOI.
Hirata T, Nakazawa M, Muraoka O, Nakayama R, Suda Y & Hibi M. (2006). Zinc-finger genes Fez and Fez-like function in the establishment of diencephalon subdivisions. Development , 133, 3993-4004. PMID: 16971467 DOI.
García-Calero E, de Puelles E & Puelles L. (2006). EphA7 receptor is expressed differentially at chicken prosomeric boundaries. Neuroscience , 141, 1887-97. PMID: 16844303 DOI.
Ribes V, Wang Z, Dollé P & Niederreither K. (2006). Retinaldehyde dehydrogenase 2 (RALDH2)-mediated retinoic acid synthesis regulates early mouse embryonic forebrain development by controlling FGF and sonic hedgehog signaling. Development , 133, 351-61. PMID: 16368932 DOI.
Junghans D, Hack I, Frotscher M, Taylor V & Kemler R. (2005). Beta-catenin-mediated cell-adhesion is vital for embryonic forebrain development. Dev. Dyn. , 233, 528-39. PMID: 15844200 DOI.
Kimura J, Suda Y, Kurokawa D, Hossain ZM, Nakamura M, Takahashi M, Hara A & Aizawa S. (2005). Emx2 and Pax6 function in cooperation with Otx2 and Otx1 to develop caudal forebrain primordium that includes future archipallium. J. Neurosci. , 25, 5097-108. PMID: 15917450 DOI.
Whitlock KE. (2005). Origin and development of GnRH neurons. Trends Endocrinol. Metab. , 16, 145-51. PMID: 15860410 DOI.
Piñuela C, Rendón C, González de Canales ML & Sarasquete C. (2004). Development of the Senegal sole, Solea senegalensis forebrain. Eur J Histochem , 48, 377-84. PMID: 15718204
Villablanca JR. (2004). Counterpointing the functional role of the forebrain and of the brainstem in the control of the sleep-waking system. J Sleep Res , 13, 179-208. PMID: 15339255 DOI.
Kage T, Takeda H, Yasuda T, Maruyama K, Yamamoto N, Yoshimoto M, Araki K, Inohaya K, Okamoto H, Yasumasu S, Watanabe K, Ito H & Ishikawa Y. (2004). Morphogenesis and regionalization of the medaka embryonic brain. J. Comp. Neurol. , 476, 219-39. PMID: 15269967 DOI.
Puelles L & Rubenstein JL. (2003). Forebrain gene expression domains and the evolving prosomeric model. Trends Neurosci. , 26, 469-76. PMID: 12948657 DOI.
Zhao Y, Marín O, Hermesz E, Powell A, Flames N, Palkovits M, Rubenstein JL & Westphal H. (2003). The LIM-homeobox gene Lhx8 is required for the development of many cholinergic neurons in the mouse forebrain. Proc. Natl. Acad. Sci. U.S.A. , 100, 9005-10. PMID: 12855770 DOI.
Brox A, Puelles L, Ferreiro B & Medina L. (2003). Expression of the genes GAD67 and Distal-less-4 in the forebrain of Xenopus laevis confirms a common pattern in tetrapods. J. Comp. Neurol. , 461, 370-93. PMID: 12746875 DOI.
Hébert JM, Hayhurst M, Marks ME, Kulessa H, Hogan BL & McConnell SK. (2003). BMP ligands act redundantly to pattern the dorsal telencephalic midline. Genesis , 35, 214-9. PMID: 12717732 DOI.
González A, López JM & Marín O. (2002). Expression pattern of the homeobox protein NKX2-1 in the developing Xenopus forebrain. Brain Res. Gene Expr. Patterns , 1, 181-5. PMID: 12638129
Meléndez-Ferro M, Pérez-Costas E, Villar-Cheda B, Abalo XM, Rodríguez-Muñoz R, Rodicio MC & Anadón R. (2002). Ontogeny of gamma-aminobutyric acid-immunoreactive neuronal populations in the forebrain and midbrain of the sea lamprey. J. Comp. Neurol. , 446, 360-76. PMID: 11954035
Levers TE, Tait S, Birling MC, Brophy PJ & Price DJ. (2002). Etr-r3/mNapor, encoding an ELAV-type RNA binding protein, is expressed in differentiating cells in the developing rodent forebrain. Mech. Dev. , 112, 191-3. PMID: 11850193
Alonso A & Trujillo CM. (2002). Continuity and discontinuity of the radial scaffolding in the forebrain of a lizard embryo. Brain Res. Bull. , 57, 505-8. PMID: 11923019
Hauptmann G, Söll I & Gerster T. (2002). The early embryonic zebrafish forebrain is subdivided into molecularly distinct transverse and longitudinal domains. Brain Res. Bull. , 57, 371-5. PMID: 11922991
Marín O, Baker J, Puelles L & Rubenstein JL. (2002). Patterning of the basal telencephalon and hypothalamus is essential for guidance of cortical projections. Development , 129, 761-73. PMID: 11830575
Nelson PA, Sutcliffe JG & Thomas EA. (2002). A new UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase mRNA exhibits predominant expression in the hypothalamus, thalamus and amygdala of mouse forebrain. Brain Res. Gene Expr. Patterns , 1, 95-9. PMID: 15018805
Ohkubo Y, Chiang C & Rubenstein JL. (2002). Coordinate regulation and synergistic actions of BMP4, SHH and FGF8 in the rostral prosencephalon regulate morphogenesis of the telencephalic and optic vesicles. Neuroscience , 111, 1-17. PMID: 11955708
Bachy I, Vernier P & Retaux S. (2001). The LIM-homeodomain gene family in the developing Xenopus brain: conservation and divergences with the mouse related to the evolution of the forebrain. J. Neurosci. , 21, 7620-9. PMID: 11567052
Puelles L. (2001). Brain segmentation and forebrain development in amniotes. Brain Res. Bull. , 55, 695-710. PMID: 11595354
Ekström P, Johnsson CM & Ohlin LM. (2001). Ventricular proliferation zones in the brain of an adult teleost fish and their relation to neuromeres and migration (secondary matrix) zones. J. Comp. Neurol. , 436, 92-110. PMID: 11413549
McCarthy M, Na E, Neyt C, Langston A & Fishell G. (2001). Calcium-dependent adhesion is necessary for the maintenance of prosomeres. Dev. Biol. , 233, 80-94. PMID: 11319859 DOI.
Nery S, Wichterle H & Fishell G. (2001). Sonic hedgehog contributes to oligodendrocyte specification in the mammalian forebrain. Development , 128, 527-40. PMID: 11171336
Rohr KB, Barth KA, Varga ZM & Wilson SW. (2001). The nodal pathway acts upstream of hedgehog signaling to specify ventral telencephalic identity. Neuron , 29, 341-51. PMID: 11239427
Crossley PH, Martinez S, Ohkubo Y & Rubenstein JL. (2001). Coordinate expression of Fgf8, Otx2, Bmp4, and Shh in the rostral prosencephalon during development of the telencephalic and optic vesicles. Neuroscience , 108, 183-206. PMID: 11734354
Corbin JG, Gaiano N, Machold RP, Langston A & Fishell G. (2000). The Gsh2 homeodomain gene controls multiple aspects of telencephalic development. Development , 127, 5007-20. PMID: 11060228
Dávila JC, Guirado S & Puelles L. (2000). Expression of calcium-binding proteins in the diencephalon of the lizard Psammodromus algirus. J. Comp. Neurol. , 427, 67-92. PMID: 11042592
Shanmugalingam S, Houart C, Picker A, Reifers F, Macdonald R, Barth A, Griffin K, Brand M & Wilson SW. (2000). Ace/Fgf8 is required for forebrain commissure formation and patterning of the telencephalon. Development , 127, 2549-61. PMID: 10821754
Pombal MA & Puelles L. (1999). Prosomeric map of the lamprey forebrain based on calretinin immunocytochemistry, Nissl stain, and ancillary markers. J. Comp. Neurol. , 414, 391-422. PMID: 10516604
Hidalgo-Sánchez M, Simeone A & Alvarado-Mallart RM. (1999). Fgf8 and Gbx2 induction concomitant with Otx2 repression is correlated with midbrain-hindbrain fate of caudal prosencephalon. Development , 126, 3191-203. PMID: 10375509
Tuttle R, Nakagawa Y, Johnson JE & O'Leary DD. (1999). Defects in thalamocortical axon pathfinding correlate with altered cell domains in Mash-1-deficient mice. Development , 126, 1903-16. PMID: 10101124
Braisted JE, Tuttle R & O'leary DD. (1999). Thalamocortical axons are influenced by chemorepellent and chemoattractant activities localized to decision points along their path. Dev. Biol. , 208, 430-40. PMID: 10191056 DOI.
Wullimann MF & Puelles L. (1999). Postembryonic neural proliferation in the zebrafish forebrain and its relationship to prosomeric domains. Anat. Embryol. , 199, 329-48. PMID: 10195307
Wullimann MF, Puelles L & Wicht H. (1999). Early postembryonic neural development in the zebrafish: a 3-D reconstruction of forebrain proliferation zones shows their relation to prosomeres. Eur J Morphol , 37, 117-21. PMID: 10342441
Alcántara S, Ruiz M, D'Arcangelo G, Ezan F, de Lecea L, Curran T, Sotelo C & Soriano E. (1998). Regional and cellular patterns of reelin mRNA expression in the forebrain of the developing and adult mouse. J. Neurosci. , 18, 7779-99. PMID: 9742148
Hatanaka Y & Jones EG. (1998). Early region-specific gene expression during tract formation in the embryonic rat forebrain. J. Comp. Neurol. , 395, 296-309. PMID: 9596525
Wong CJ. (1997). Connections of the basal forebrain of the weakly electric fish, Eigenmannia virescens. J. Comp. Neurol. , 389, 49-64. PMID: 9390759
Shimamura K & Rubenstein JL. (1997). Inductive interactions direct early regionalization of the mouse forebrain. Development , 124, 2709-18. PMID: 9226442
Parmantier E, Braun C, Thomas JL, Peyron F, Martinez S & Zalc B. (1997). PMP-22 expression in the central nervous system of the embryonic mouse defines potential transverse segments and longitudinal columns. J. Comp. Neurol. , 378, 159-72. PMID: 9120057
Alvarez-Bolado G, Rosenfeld MG & Swanson LW. (1995). Model of forebrain regionalization based on spatiotemporal patterns of POU-III homeobox gene expression, birthdates, and morphological features. J. Comp. Neurol. , 355, 237-95. PMID: 7608343 DOI.
Papalopulu N. (1995). Regionalization of the forebrain from neural plate to neural tube. Perspect Dev Neurobiol , 3, 39-52. PMID: 8542255
de la Llave R S & Tompaidis. (1994). Nature of singularities for analyticity domains of invariant curves. Phys. Rev. Lett. , 73, 1459-1463. PMID: 10056799 DOI.
Price M. (1993). Members of the Dlx- and Nkx2-gene families are regionally expressed in the developing forebrain. J. Neurobiol. , 24, 1385-99. PMID: 7901324 DOI.
Bulfone A, Puelles L, Porteus MH, Frohman MA, Martin GR & Rubenstein JL. (1993). Spatially restricted expression of Dlx-1, Dlx-2 (Tes-1), Gbx-2, and Wnt-3 in the embryonic day 12.5 mouse forebrain defines potential transverse and longitudinal segmental boundaries. J. Neurosci. , 13, 3155-72. PMID: 7687285
- 3DMRI - Three-dimensional magnetic resonance imaging. A new technique that allows 3D analysis of embryonic structures. (More? Magnetic Resonance Imaging)
- 3rd ventricle - a fluid-filled space formed from neural tube lumen, located within the diencephalon (from the primary vesicle prosencephalon, forebrain).
- 4th ventricle - a fluid-filled space formed from neural tube lumen, located within the rhombencephalon (from the primary vesicle, hindbrain).
- adenohypophysis - (anterior pituitary) = 3 parts pars distalis, pars intermedia, pars tuberalis.
- afferent - refers to the direction of conduction from the periphery toward the central nervous system. Efferent is in the opposite direction.
- alar plate - embryonic dorsolateral region of the neural tube forming at spinal cord level dorsal horns (afferent) and brain level different structures.
- anlage - (German = primordium) structure or cells that will form a future adult structure.
- arachnoid mater - (G.) spider web-like used in reference to the middle layer of the brain meninges.
- astrocytes - cells named by their "star-like" branching appearance, are the most abundant glial cells in the brain, important for the blood-brain barrier.
- basal ganglia - (basal nuclei) neural structure derived from the secondary vesicle telencephalon (endbrain) structure from the earlier primary vesicle prosencephalon (forebrain).
- basal plate - embryonic ventrolateral region of the neural tube forming at spinal cord level ventral horns (efferent) and brain level different structures.
- brachial plexus - mixed spinal nerves innervating the upper limb form a complex meshwork (crossing).
- brain - general term for the central nervous system formed from 3 primary vesicles.
- buccopharyngeal membrane - (oral membrane) at cranial (mouth) end of gastrointestinal tract (GIT) where surface ectoderm and GIT endoderm meet. (see also cloacal membrane).
- cauda equina - (horse's tail) caudal extension of the mature spinal cord.
- central canal - lumen, cavity of neural tube within the spinal cord. Space is continuous with ventricular system of the brain.
- central cerebral sulcus - (central fissure, fissure of Rolando, Rolandic fissure) fold in the cerebral cortex associated with the sensorimotor cortex.
- cerebral aqueduct - ventricular cavity within the mesencephalon.
- cervical flexure - most caudal brain flexure (of 3) between spinal cord and rhompencephalon.
- choroid plexus - specialized vascular plexus responsible for secreting ventricular fluid that with further additions becomes cerebrospinal fluid (CSF).
- cloacal membrane - at caudal (anal) end of gastrointestinal tract (GIT) where surface ectoderm and GIT endoderm meet forms the openings for GIT, urinary, reproductive tracts. (see also buccopharyngeal membrane).
- connectome - term describing the detailed map of neural connections in the central nervous system.
- cortex - - CNS structure derived from the secondary vesicle telencephalon (endbrain) from the earlier primary vesicle prosencephalon (forebrain).
- cortical plate - outer neural tube region which post-mitotic neuroblasts migrate too along radial glia to form adult cortical layers.
- cranial flexure - (=midbrain flexure) most cranial brain flexure (of 3) between mesencephalon and prosencephalon.
- diencephalon - the caudal portion of forebrain after it divides into 2 parts in the 5 secondary vesicle brain (week 5). (cavity- 3rd ventricle) Forms the thalmus and other nuclei in the adult brain. (sc-My-Met-Mes-Di-Tel)
- dorsal root ganglia - (spinal ganglia) sensory ganglia derived from the neural crest lying laterally paired and dorsally to the spinal cord (in the embryo found ventral to the spinal cord). Connects centrally with the dorsal horn of the spinal cord.
- dura mater- "tough" (Latin, mater = mother) used in reference to the tough outer layer of the brain meninges.
- efferent - refers to the direction of conduction from the central nervous system toward the periphery. Afferent is in the opposite direction.
- ependyma - epithelia of remnant cells after neurons and glia have been generated and left the ventricular zone.
- floorplate - early forming thin region of neural tube closest to the notochord.
- ganglia - (pl. of ganglion) specialized neural cluster within either the CNS or PNS.
- glia - supporting, non-neuronal cells of the nervous system. Generated from the same neuroepithelial stem cells that form neurons in ventricular zone of neural tube. Form astrocytes, oligodendrocytes.
- grey matter - neural regions containing cell bodies (somas) of neurons. In the brain it is the outer layer, in the spinal cord it is inner layer. (see white matter white matter).
- growth factor - usually a protein or peptide that will bind a cell membrane receptor and then activates an intracellular signaling pathway. The function of the pathway will be to alter the cell directly or indirectly by changing gene expression. (eg SHH).
- HOX - (homeobox) family of transcription factors that bind DNA and activate gene expression. Expression of different Hox genes along neural tube defines rostral-caudal axis and segmental levels.
- hydrocephalus - abnormality as the result of an imbalance between the rate at which the CSF is being formed and the rate at which the CSF is passing through the arachnoidal villi back into the blood (hydrocephalus rate is a function of the degree of imbalance in these two). Very small imbalance exhibit subtle, if any, symptoms. Large imbalances will have rapidly evolving symptoms of unmistakable import.
- isthmus- (G. narrow passage).
- lamina terminalis - anterior region of brain where cranial neuropore closes.
- lumbar plexus - mixed spinal nerves innervating the lower limb form a complex meshwork (crossing).
- mantle layer - layer of cells generated by first neuroblasts migrating from the ventricular zone of the neural tube. Layers are rearranged during development of the brain and spinal cord. (Ven-Man-Mar-CP)
- marginal zone - layer of processes from neuroblasts in mantle layer. (Ven-Man-Mar-CP)
- mater - (Latin, mater = mother) used in relation to the 3 layers of the meninges.
- meninges - mesenchyme surrounding neural tube forms 3 layer (Dura-, pia-, arachnoid- mater) connective tissue sheath of nervous system. (D-P-A-cns)
- mesencephalon - (midbrain), the middle portion of the 3 primary vesicle brain (week 4). (sc-R-M-P)
- metencephalon - the cranial portion of hindbrain after it divides into 2 parts in the 5 secondary vesicle brain (week 5). Forms the pons and cerebellum in the adult brain. (sc-My-Met-Mes-Di-Tel)
- microglia - CNS innate immune cells that have a macrophage function, derive from yolk sac progenitor cells migrating into the CNS. microglia
- myelencephalon - the caudal portion of hindbrain after it divides into 2 parts in the 5 secondary vesicle brain (week 5). Forms the medulla in the adult brain. (sc-My-Met-Mes-Di-Tel)
- neural tube - neural plate region of ectoderm pinched off to form hollow ectodermal tube above notochord in mesoderm.
- neural tube defect - (NTD) any developmental abnormality that affects neural tube development. Commonly failure of neural tube closure.
- neuroblast - undifferentiated neuron found in ventricular layer of neural tube.
- neurohypophysis - (posterior pituitary; pas nervosa)
- neuromere - (prosomere) the model units for segmental brain development regions based upon a series of neural tube transverse subunits.
- neuron - The cellur "unit" of the nervous system, transmitting signals between neurons and other cells. The post-mitotic cells generated from neuroepithelial stem cells (neuroblasts) in ventricular zone of neural tube.
- neuropore - opening at either end of neural tube cranial (rostral, anterior) neuropore closes (day 25) about 2 days before caudal (posterior) that closes at somite level 32 to 34. Neural Tube Defects (NTDs) can be due to failure of these two neuropores to close.
- notochord - rod of cells lying in mesoderm layer ventral to the neural tube, induces neural tube and secretes sonic hedgehog which "ventralizes" the neural tube.
- olfactory bulb - (cranial nerve I, CN I) bipolar neurons from nasal epithelium project axons through cribiform palate into olfactory bulb of the brain associated with smell.
- optic nerve - (cranial nerve II, CN II) retinal ganglion neurons project from the retina as a tract into the brain (at the level of the diencephalon) associated with vision.
- optic vesicle - diencephalon region of neural tube outgrowth that forms the primordia of the retina associated with vision.
- opercularization - during fetal development of the sensorimotor cortex, the insula (located deep within the lateral sulcus) begins to invaginate from the surface of the immature cerebrum, until at term, the opercula completely cover the insula.
- otocyst - (otic vesicle) sensory placode that sinks into mesoderm to form spherical vesicle (stage 13/14 embryo) that will form components of the inner ear associated with hearing.
- pharyngeal arch - (branchial arch, Gk. gill) form the main structures of the head and neck. Humans have 5 arches appearing in week 4 that form 4 external swellings, each arch has a pouch, membrane and cleft.
- pharynx - uppermost end of GIT, beginning at the buccopharyngeal membrane and at the level of the pharyngeal arches.
- pia mater - (G.) (L. pius = soft, faithful + mater = mother) delicate vascular membrane which adheres to surface of brain and spinal cord, faithfully following their contours, the inner layer of the brain meninges.
- placode - specialized regions of ectoderm which form components of the sensory apparatus.
- pontine flexure - middle brain flexure (of 3) between cervical and cranial flexure in opposite direction, also generates thin roof of rhombencephalon and divides it into myelencephalon and metencephalon. ( sc-^V^ )
- posterior insula - during sensorimotor cortex development this region is composed of the anterior and posterior long insular gyri and the postcentral insular sulcus, which separates them.
- prosencephalon - (forebrain), the most cranial portion of the 3 primary vesicle brain (week 4). (sc-R-M-P)
- prosomere - (neuromere) a model for segmental brain development based upon a series of neural tube transverse subunits. PMID 12948657
- Rathke's pouch - a portion of the roof of the pharynx pushes upward towards the floor of the brain forming the anterior pituitary (adenohypophysis, pars distalis, pars tuberalis pars intermedia). Where it meets a portion of the brain pushing downward forming the posterior pituitary (neurohypophysis, pars nervosa). Rathke's pouch eventually looses its connection with the pharynx.
- rhombencephalon - (hindbrain), the most caudal portion of the 3 primary vesicle brain (week 4). (sc-R-M-P)
- rhombic lip - metencephalon posterior part extending from the roof of the fourth ventricle to dorsal neuroepithelial cells that contributes to the cerebellum.
- roofplate - early forming thin region of neural tube closest to the overlying ectoderm.
- spinal cord - caudal end of neural tube that does not contribute to brain. Note: the process of secondary neuralation contributes the caudal end of the spinal cord.
- spinal ganglia - (dorsal root ganglia, drg) sensory ganglia derived from the neural crest lying laterally paired and dorsally to the spinal cord (in the embryo found ventral to the spinal cord). Connects centrally with the dorsal horn of the spinal cord.
- spinal nerve - mixed nerve (motor and sensory) arising as latera pairs at each vertebral segmental level.
- sonic hedgehog - (shh) secreted growth factor that binds patched (ptc) receptor on cell membrane. SHH function is different for different tissues in the embryo. In the nervous system, it is secreted by the notochord, ventralizes the neural tube, inducing the floor plate and motor neurons.
- sulcus - (L. furrow) groove.
- sulcus limitans - longitudinal lateral groove in neural tube approx. midway between roofplate and floorplate. Groove divides alar (dorsal) and basal (ventral) plate regions.
- telencephalon - the cranial portion of forebrain after it divides into 2 parts in the 5 secondary vesicle brain (week 5). (cavity- lateral ventricles and some of 3rd ventricle) Forms the cerebral hemispheres in the adult brain. (sc-My-Met-Mes-Di-Tel)
- thalamus - (G. thalamos= bedchamber) cns nucleus, lateral to 3rd ventricle, paired (pl thalami).
- thyroid hormone - hormone required for brain development. T3 (3,5,3′-triiodothyronine) binding to nuclear receptors then act as a transcription factor in both neurons and glial cells. iodine deficiency
- transcription factor - a factor (protein or protein with steroid) that binds to DNA to alter gene expression, usually to activate. (eg steroid hormone+receptor, Retinoic acid+Receptor, Hox, Pax, Lim, Nkx-2.2)
- trigeminal ganglion - (cranial nerve V, CN V) first arch ganglion, very large and has 3 portions.
- vagal ganglion - (cranial nerve X, CN X) fourth and sixth arch ganglion, innervates the viscera and heart.
- ventricles - the fluid-filled interconnected cavity system with the brain. Fluid (cerebrospinal fluid, CSF) is generated by the specialized vascular network, the choroid plexus. The ventricles are directly connected to the spinal canal (within the spinal cord).
- ventricular zone - Neuroepithelial cell layer of neural tube closest to lumen. Neuroepithelial cells generate neurons, glia and ependymal cells. (Ven-Man-Mar-CP)
- vestibulocochlear nerve - (cranial nerve VIII, CN VIII, also called statoacoustic)
- white matter - - neural regions containing processes (axons) of neurons. In the brain it is the inner layer, in the spinal cord it is outer layer. (see grey matter).
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Cite this page: Hill, M.A. (2020, July 8) Embryology Neural - Prosomere. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Neural_-_Prosomere
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