... that they cross the ventral midline only once. However, the underlying mechanisms remain to be elucidated. We have found that both endocytosis and recycling of Robo1 receptor are crucial for modulating Slit sensitivity in vertebrate commissural axons. Robo1 endocytosis and its recycling back to the cell surface...

...-shaped preplacodal ectoderm in which the precursors of individual placodes are intermingled. However, fate-map studies indicated that cells positioned at the preplacodal midline give rise to only the adenohypophyseal placode, suggesting a unique organization of these precursors within the preplacode...

... genes and enhancers. Analysis of Drosophila CNS midline cell development provides a useful system for studying transcriptional regulation at the genomic level due to a large, well-characterized set of midline-expressed genes and in vivo validated enhancers. In this study, FAIRE-seq on FACS-purified...

...Marie-Sophie Cate; Sangeetha Gajendra; Samantha Alsbury; Thomas Raabe; Guy Tear; Kevin J. Mitchell The outgrowth of many neurons within the central nervous system is initially directed towards or away from the cells lying at the midline. Recent genetic evidence suggests that a simple model...

...Jana Slováková; Ana Carmena Vertebrates and insects alike use glial cells as intermediate targets to guide growing axons. Similar to vertebrate oligodendrocytes, Drosophila midline glia ensheath and separate axonal commissures. Neuron-glia interactions are crucial during these events, although...

... for correspondence ( [email protected] ; [email protected] ) Competing interests statement The authors declare no competing financial interests. 14 1 2011 © 2011. 2011 Motoneuron Ascidian Evolution Spinal cord BMP Shh Nodal Midline Dorsal ventral pattern One of the major...

...Hope A. Coleman; Juan-Pablo Labrador; Rebecca K. Chance; Greg J. Bashaw Slits and their Roundabout (Robo) receptors mediate repulsive axon guidance at the Drosophila ventral midline and in the vertebrate spinal cord. Slit is cleaved to produce fragments with distinct signaling properties...

... of the dorsoventral (DV) axes and midline determination in early embryos. In frog embryos, consistent physiological and molecular asymmetries manifest by the second cell cleavage; however, models based on extracellular fluid flow at the node predict correct de novo asymmetry orientation during neurulation. We...

... of the GMC and the fate specification of daughter cells of the GMC. Our results with midline ( mid ),which encodes a T-box protein, in a typical lineage,NB4-2→GMC-1→RP2/sib, suggest that at least part of the process operates in GMCs. That is, a GMC or a neuronal identity need not be determined at the NB...

... at the Drosophila midline. Surprisingly, in contrast to vertebrate DCC, P3 does not mediate receptor self-association, and self-association is not sufficient to promote Fra-dependent attraction. We also show that in contrast to previous findings,the cytoplasmic domain of Fra is not required for axonal localization...

... in non-erythroid cells during protein targeting and membrane domain formation. Here, we demonstrate that β-Spectrin is required in neurons for proper midline axon guidance in the Drosophila embryonic CNS. In β -spectrin mutants many axons inappropriately cross the CNS midline, suggesting a role forβ...

... developmental malformations attributed to SLOS occur in tissues and organs where Hh signaling is required for development,but the precise role of DHCR7 deficiency in this disease remains murky. We report that DHCR7 and Sonic Hedgehog ( Shh ) are co-expressed during midline development in Xenopus embryos. DHCR7...

... tube vascular patterning signal. Thus, the neural tube is the first structure identified as a midline signaling center for embryonic vascular pattern formation in higher vertebrates, and VEGFA is a necessary component of the neural tube vascular patterning signal. These data suggest a model whereby...

... related to midline crossing. Additionally, we show that the axon guidance molecules roundabout2 and roundabout3 ( robo2/3 ) are necessary for serotonergic neuron differentiation and function independently of their ligand, slit . Loss of robo2 or robo3 causes a loss of SerT expression in about half...

... resulted in profound failure of dorsal midline brain structure formation and perinatal death,presumably by interfering with expression of downstream genes. Interruption of a single allele prevented formation of the subcommissural organ, a structure important for cerebrospinal fluid flow through...

... but not in the mutant. Ectopic Nodal expression in right LPM also induced Lefty1 expression in the floor plate. Nodal signaling thus initiates asymmetric Nodal expression in LPM and induces Lefty1 at the midline. Monitoring of Nodal activity in wild-type and Foxh1 mutant embryos suggested that Nodal activity travels...

... and midline function. We report that Notch signalling, which previously had not been implicated in this morphogenetic process, is required for normal left-right determination in mice. We show, that the loss-of-function of the delta 1( Dll1 ) gene causes a situs ambiguous phenotype, including randomisation...

... that Xdsh function was required specifically in the midline for normal neural tube closure. We suggest that the inherent movement of the neural folds can accomplish only a finite amount of medial progress and that convergent extension of the midline is necessary to reduce the distance between the nascent...

...Marios Georgiou; Guy Tear In the absence of Commissureless (Comm) function, axons are unable to extend across the central nervous system midline. Comm downregulates levels of Roundabout (Robo), a receptor for the midline repellent Slit, in order to allow axons to cross the midline. comm transcript...

...Andrew J. Latimer; Xinhong Dong; Youlia Markov; Bruce Appel Different cell types that occupy the midline of vertebrate embryos originate within the Spemann-Mangold or gastrula organizer. One such cell type is hypochord, which lies ventral to notochord in anamniote embryos. We show that hypochord...