... lamination and cortical arealization, but whether and how its level of expression affects its function is unclear. We studied the developing cortex of PAX77 YAC transgenic mice carrying several copies of the human PAX6 locus with its full complement of regulatory regions. We found that PAX77 embryos express...

... intrathalamica (ZLI). Here, we describe formation of the ZLI in zebrafish in relation to expression of sonic hedgehog ( shh ) and tiggy-winkle hedgehog ( twhh ), and to development of the forebrain regions that flank the ZLI: the prethalamus and thalamus. We find that enhanced Hh signalling increases the size...

... and regionalization( Fig. 6 ). In contrast, mutation of the HD affected only subtle aspects of the boundary delineating the dorsal and ventral telencephalon. Since the canonical form of the PD binds to both Pax6 consensus sites (P6CON, 5aCON) and the Pax6(5a) isoform binds exclusively to the 5aCON site ( Epstein et...

... OV at E9.5( Fig. 1A-D ; Fig. 4A ) and E10.0( Fig. 1E-H ), whereas Pax2 immunoreactivity was never detected in the Pax6-positive surface ectoderm( Fig. 1B,F,L ; Fig. 4A ). By E12.5, Pax6 expression started to be downregulated in the optic stalk region, but the signal was still abundant in the NR...

... regionalization and potentially the patterning of thalamic projections. We show that reduction of Fgf8 levels in hypomorphic mouse mutants shifts early gradients of gene expression rostrally, thereby modifying the molecular identity of rostral cortical progenitors. This shift correlates with a reduction...

...Daisuke Kobayashi; Makoto Kobayashi; Ken Matsumoto; Toshihiko Ogura; Masato Nakafuku; Kenji Shimamura Regionalization of the embryonic brain is achieved through multi-step processes that operate sequentially and/or simultaneously. Localized sources of various signaling molecules act as organizing...

... of sympathetic neurons . Development 126 , 4087 – 4094 . 10.1242/dev.126.18.4087 Szebenyi , G. , Callaway , J. L. , Dent , E. W. and Kalil , K. ( 1998 ). Interstitial branches develop from active regions of the axon demarcated by the primary growth cone during pausing behaviors...

...Lori Sussel; Oscar Marin; Shioko Kimura; John L. R. Rubenstein The telencephalon is organized into distinct longitudinal domains: the cerebral cortex and the basal ganglia. The basal ganglia primarily consists of a dorsal region (striatum) and a ventral region (pallidum). Within the telencephalon...

... to study the initiation and regionalization of the body plan. A complete body plan forms in each LBI by 36 hours in culture, and normal craniocaudal, dorsoventral, and mediolateral axes are re-established. Thus, reconstitution of the organizer is sufficient to re-establish a fully patterned body plan. LBIs...

... integrator of midbrain-hindbrain boundary development. * Author for correspondence (e-mail: brand@sun0.urz.uni-heidelberg.de ) © 1998 by Company of Biologists 1998 Midbrain-hindbrain organizer Neurogenesis Regionalization Neural patterning Splicing Pax genes no isthmus Zebrafish...

... or dispensable for others. * Author for correspondence (e-mail: brand@sun0.urz.uni-heidelberg.de ) 03 06 1998 02 04 1998 © 1998 by Company of Biologists 1998 Neurogenesis Regionalization Fgf8 acerebellar Pax genes Midbrain Hindbrain Organizer Zebrafish Somitogenesis...

... is no longer able to induce regions of the nervous system anterior to the hindbrain. Stage 4 + is marked by the emergence from the node of a group of cells, the prechordal mesendoderm. Here we have investigated whether the prechordal region possesses the lost functions of the organizer, using quail-chick...

...Michio Yoshida; Yoko Suda; Isao Matsuo; Norimasa Miyamoto; Naoki Takeda; Shigeru Kuratani; Shinichi Aizawa ABSTRACT The genes Emx1 and Emx2 are mouse cognates of a Drosophila head gap gene, empty spiracles , and their expression patterns have suggested their involvement in regional patterning...

... antibodies shows that the MHB region and the dorsal and ventral midbrain are absent or abnormal, but that the rostral hindbrain is unaffected with the exception of the cerebellum. Using markers that are expressed during its formation ( eng, wnt1 and pax-b) , we find that the MHB region is already...

... binding assays and in vivo expression analysis in transgenic mice to gain insight into the genetic events that lead to regionalization of the developing brain. A minimum En-2 1.0 kb enhancer fragment was defined and found to contain multiple positive and negative regulatory elements that function...

...Gord Fishell ABSTRACT One of the early steps in the regionalization of the CNS is the subdivision of the forebrain into dorsal and basal telen-cephalic ventricular zones. These ventricular zones give rise to the cortex and striatum respectively, in the mature brain. Previous work suggests...

... in mesodermal regionalization and somitic differentiation. Mox-1 is genetically linked to the keratin and Hox-2 genes of chromosome 11, while Mox-2 maps to chromosome 12. At primitive streak stages (approximately 7.0 days post coitum), Mox-1 is expressed in mesoderm lying posterior of the future primordial head...

...Kate G. Storey; James M. Crossley; Eddy M. De Robertis; Wendie E. Norris; Claudio D. Stern ABSTRACT Induction and regionalisation of the chick nervous system were investigated by transplanting Hensen’s node into the extra-embryonic region (area opaca margin) of a host embryo. Chick/quail chimaeras...