Talk:Neural - Rhombencephalon Development
Clonal analysis in mice underlines the importance of rhombomeric boundaries in cell movement restriction during hindbrain segmentation
PLoS One. 2010 Apr 12;5(4):e10112.
Jimenez-Guri E, Udina F, Colas JF, Sharpe J, Padrón-Barthe L, Torres M, Pujades C.
Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain. Abstract BACKGROUND: Boundaries that prevent cell movement allow groups of cells to maintain their identity and follow independent developmental trajectories without the need for ongoing instructive signals from surrounding tissues. This is the case of vertebrate rhombomeric boundaries. Analysis in the developing chick hindbrain provided the first evidence that rhombomeres are units of cell lineage. The appearance of morphologically visible rhombomeres requires the segment restricted expression of a series of transcription factors, which position the boundaries and prefigure where morphological boundaries will be established. When the boundaries are established, when the cells are committed to a particular rhombomere and how they are organized within the hindbrain are important questions to our understanding of developmental regionalization.
METHODOLOGY/PRINCIPAL FINDINGS: Sophisticated experimental tools with high-resolution analysis have allowed us to explore cell lineage restriction within the hindbrain in mouse embryos. This novel strategy is based on knock-in alleles of ubiquitous expression and allows unrestricted clonal analysis of cell lineage from the two-cell stage to the adult mouse. Combining this analysis with statistical and mathematical tools we show that there is lineage compartmentalization along the anteroposterior axis from very early stages of mouse embryonic development.
CONCLUSIONS: Our results show that the compartment border coincides with the morphological boundary in the mouse hindbrain. The restriction of the cells to cross rhombomeric boundaries seen in chick is also observed in mouse. We show that the rhombomeric boundaries themselves are involved in cell movement restriction, although an underlying pre-pattern during early embryonic development might influence the way that cell populations organize.
PMID: 20404937 http://www.ncbi.nlm.nih.gov/pubmed/20404937
Boundary cells regulate a switch in the expression of FGF3 in hindbrain rhombomeres
Sela-Donenfeld D, Kayam G, Wilkinson DG. BMC Dev Biol. 2009 Feb 20;9:16. PMID: 19232109
Rhombomere-specific analysis reveals the repertoire of genetic cues expressed across the developing hindbrain
Chambers D, Wilson LJ, Alfonsi F, Hunter E, Saxena U, Blanc E, Lumsden A. Neural Dev. 2009 Feb 10;4:6. PMID: 19208226
Hox genes in neural patterning and circuit formation in the mouse hindbrain
Narita Y, Rijli FM. Curr Top Dev Biol. 2009;88:139-67. Review. PMID: 19651304
Compartments and their boundaries in vertebrate brain development
Kiecker C, Lumsden A. Nat Rev Neurosci. 2005 Jul;6(7):553-64. Review. PMID: 15959467
Segmentation and compartition in the early avian hindbrain
Lumsden A. Mech Dev. 2004 Sep;121(9):1081-8. Review. PMID: 15296973
Segmental identity and cerebellar granule cell induction in rhombomere 1
Eddison M, Toole L, Bell E, Wingate RJ. BMC Biol. 2004 Jun 15;2:14. PMID: 15198802
Rhombencephalic neural crest segmentation is preserved throughout craniofacial ontogeny
Development. 1996 Oct;122(10):3229-42.
Köntges G, Lumsden A.
MRC Brain Development Programme, Department of Developmental Neurobiology, UMDS, Guy's Hospital, London, UK.
Abstract To investigate the influence of hindbrain segmentation on craniofacial patterning we have studied the long term fate of neural crest (NC) subpopulations of individual rhombomeres (r), using quail-chick chimeras. Mapping of all skeletal and muscle connective tissues developing from these small regions revealed several novel features of the cranial neural crest. First, the mandibular arch skeleton has a composite origin in which the proximal elements are r1+r2 derived, whereas more distal ones are exclusively midbrain derived. The most proximal region of the lower jaw is derived from second arch (r4) NC. Second, both the lower jaw and tongue skeleton display an organisation which precisely reflects the rostrocaudal order of segmental crest deployment from the embryonic hindbrain. Third, cryptic intraskeletal boundaries, which do not correspond to anatomical landmarks, form sharply defined interfaces between r1+r2, r4 and r6+r7 crest. Cells that survive the early apoptotic elimination of premigratory NC in r3 and r5 are restricted to tiny contributions within the 2nd arch (r4) skeleton. Fourth, a highly constrained pattern of cranial skeletomuscular connectivity was found that precisely respects the positional origin of its constitutive crest: each rhombomeric population remains coherent throughout ontogeny, forming both the connective tissues of specific muscles and their respective attachment sites onto the neuro- and viscerocranium. Finally, focal clusters of crest cells, confined to the attachment sites of branchial muscles, intrude into the otherwise mesodermal cranial base. In the viscerocranium, an equally strict, rhombomere-specific matching of muscle connective tissues and their attachment sites is found for all branchial and tongue (hypoglossal) muscles. This coherence of segmental crest populations explains how cranial skeletomuscular pattern can be implemented and conserved despite evolutionary changes in the shapes of skeletal elements.