TY  - JOUR
AB  - Pancreas organogenesis is a highly dynamic process where neighboring tissue interactions lead to dynamic changes in gene regulatory networks that orchestrate endocrine, exocrine, and ductal lineage formation. To understand the spatio-temporal regulatory logic we have used the Forkhead transcription factor Foxa2-Venus fusion (FVF) knock-in reporter mouse to separate the FVF+ pancreatic epithelium from the FVF− surrounding tissue (mesenchyme, neurons, blood, and blood vessels) to perform a genome-wide mRNA expression profiling at embryonic days (E) 12.5–15.5. Annotating genes and molecular processes suggest that FVF marks endoderm-derived multipotent epithelial progenitors at several lineage restriction steps, when the bulk of endocrine, exocrine and ductal cells are formed during the secondary transition. In the pancreatic epithelial compartment, we identified most known endocrine and exocrine lineage determining factors and diabetes-associated genes, but also unknown genes with spatio-temporal regulated pancreatic expression. In the non-endoderm-derived compartment, we identified many well-described regulatory genes that are not yet functionally annotated in pancreas development, emphasizing that neighboring tissue interactions are still ill defined. Pancreatic expression of over 635 genes was analyzed with the mRNA in situ hybridization Genepaint public database. This validated the quality of the profiling data set and identified hundreds of genes with spatially restricted expression patterns in the pancreas. Some of these genes are also targeted by pancreatic transcription factors and show active chromatin marks in human islets of Langerhans. Thus, with the highest spatio-temporal resolution of a global gene expression profile during the secondary transition, our study enables to shed light on neighboring tissue interactions, developmental timing and diabetes gene regulation.
AU  - Willmann, S.
AU  - Müller, N.S.
AU  - Engert, S.
AU  - Sterr, M.
AU  - Burtscher, I.
AU  - Raducanu, A.
AU  - Irmler, M.
AU  - Beckers, J.
AU  - Sass, S.
AU  - Theis, F.J.
AU  - Lickert, H.
C1  - 47455
C2  - 39320
CY  - Amsterdam
SP  - 51-64
TI  - The global gene expression profile of the secondary transition during pancreatic development.
JO  - Mech. Dev.
VL  - 139
PB  - Elsevier Science Bv
PY  - 2016
SN  - 0925-4773
ER  - 

TY  - JOUR
AB  - Unveiling mechanisms driving specification, recruitment and regeneration of melanophores is key in understanding melanin-related disorders. This study reports on the applicability of a hybrid focus optoacoustic microscope (HFOAM) for volumetric tracking of migratory melanophores in developing zebrafish. The excellent contrast from highly-absorbing melanin provided by the method is shown to be ideal for label-free dynamic visualization of melanophores in their unperturbed environment. We established safe laser energy levels that enable high-contrast longitudinal tracking of the cells over an extended period of developmental time without causing cell toxicity or pigment bleaching. Owing to its hybrid optical and acoustic resolution, the new imaging technique can be seamlessly applied for noninvasive studies of both optically-transparent larval as well as adult stages of the zebrafish model organism, which is not possible using other optical microscopy methods.
AU  - Kneipp, M.
AU  - Estrada, H.
AU  - Lauri, A.
AU  - Turner, J.E.
AU  - Ntziachristos, V.
AU  - Westmeyer, G.G.
AU  - Razansky, D.
C1  - 46930
C2  - 39062
SP  - 300-304
TI  - Volumetric tracking of migratory melanophores during zebrafish development by optoacoustic microscopy.
JO  - Mech. Dev.
VL  - 138
PY  - 2015
SN  - 0925-4773
ER  - 

TY  - JOUR
AB  - Sonic hedgehog (Shh) is well known as the molecule responsible for the induction and maintenance of ventral neural tube structures. Recent data have shown that ventral neuronal populations react differentially to the amount of this morphogen not only in the spinal cord, but also in more rostral parts of the brain, like the midbrain. A dorsal expansion in the Shh expression domain modifies the differentiation program in this territory. The lack of Shh produces alterations in the development of this area as well. Here, for the first time, we analyze in detail the development of the different mesencephalic basal nuclei in the absence of Shh. We report that the oculomotor complex is lost, the dopaminergic populations are strongly affected but the red nucleus is maintained. These results point out that not all the midbrain neuronal populations are dependent on Shh for their maintenance, as previously thought. Based on our results and recently published data, we suggest the existence of a specific genetic pathway for the specification of the mesencephalic red nucleus. Foxa2 could be the candidate gene that might control this genetic pathway.
AU  - Perez-Balaguer, A.*
AU  - Puelles, E.*
AU  - Wurst, W.
AU  - Martinez, S.*
C1  - 1025
C2  - 26270
SP  - 301-313
TI  - Shh dependent and independent maintenance of basal midbrain.
JO  - Mech. Dev.
VL  - 126
IS  - 5-6
PB  - Elsevier Science Bv
PY  - 2009
SN  - 0925-4773
ER  - 

TY  - JOUR
AU  - Schroeder, T.
AU  - Meier-Stiegen, F.*
AU  - Schwanbeck, R.*
AU  - Eilken, H.M.
AU  - Nishikawa, S.*
AU  - Häsler, R.*
AU  - Schreiber, S.*
AU  - Bornkamm, G.W.
AU  - Nishikawa, S.-I.*
AU  - Just, U.
C1  - 4438
C2  - 23774
SP  - 570-579
TI  - Activated Notch1 alters differentiation of embryonic stem cells into mesodermal cell lineages at multiple stages of development.
JO  - Mech. Dev.
VL  - 123
PY  - 2006
SN  - 0925-4773
ER  - 

TY  - JOUR
AU  - Bellipanni, G.*
AU  - Rink, E.*
AU  - Bally-Cuif, L.
C1  - 10003
C2  - 22571
SP  - 215-220
TI  - Cloning of two tryptophan hydroxylase genes expressed in the diencephalon of the developing zebrafish brain. 
JO  - Mech. Dev.
VL  - 119
PY  - 2002
SN  - 0925-4773
ER  - 

TY  - JOUR
AU  - Pelletier, I.
AU  - Bally-Cuif, L.
AU  - Ziegler, I.
C1  - 21746
C2  - 19941
SP  - 99-103
TI  - Cloning and developmental expression of zebrafish GTP cyclohydrolase I.
JO  - Mech. Dev.
VL  - 109
PY  - 2001
SN  - 0925-4773
ER  - 

TY  - JOUR
AU  - Vetter, K.*
AU  - Wurst, W.
C1  - 2785
C2  - 22817
SP  - 123-125
TI  - Expression of a novel mouse gene 'mbFZb' in distinct regions of the developing nervous system and the adult brain.
JO  - Mech. Dev.
VL  - 100
PY  - 2001
SN  - 0925-4773
ER  - 

TY  - JOUR
AB  - The Delta1 gene encodes one of the Notch ligands in mice. Delta1 is expressed during early embryogenesis in a complex and dynamic pattern in the paraxial mesoderm and neuroectoderm, and is essential for normal somitogenesis and neuronal differentiation. Molecular components thought to act in response to ligand binding and Notch activation have been identified in different species. In contrast, little is known about the transcriptional regulation of Notch receptors and their ligands. As a first step to identify upstream factors regulating Delta1 expression in different tissues, we searched for cis-regulatory regions in the Delta1 promoter able to direct heterologous gene expression in a tissue specific manner in transgenic mice. Our results show that a 4.3 kb genomic DNA fragment of the Delta1 gene is sufficient in a lacZ reporter transgene to reproduce most aspects of Delta1 expression from the primitive streak stage to early organogenesis. Using a minimal Delta1 promoter we also show that this upstream region contains distinct regulatory modules that individually direct tissue-specific transgene expression in subdomains of the endogenous expression pattern. It appears that expression in the paraxial mesoderm depends on the interaction of multiple positive and negative regulatory elements. We also find that at least some regulatory sequences required for transgene expression in subdomains of the neural tube have been maintained during the evolution of mammals and teleost fish, suggesting that part of the regulatory network that controls expression of Delta genes may be conserved.
AU  - Beckers, J.
AU  - Caron, A.*
AU  - Hrabě de Angelis, M.
AU  - Hans, S.*
AU  - Campos-Ortega, J.A.*
AU  - Gossler, A.*
C1  - 22301
C2  - 21107
SP  - 23-34
TI  - Distinct regulatory elements direct Delta1 expression in the nervous system and paraxial mesoderm of transgenic mice.
JO  - Mech. Dev.
VL  - 95
PY  - 2000
SN  - 0925-4773
ER  - 

TY  - JOUR
AB  - Rib-vertebrae (rv) is an autosomal recessive mutation in mouse that affects the morphogenesis of the vertebral column. Axial skeleton defects vary along the anterior-posterior body axis, and include split vertebrae and neural arches, and fusions of adjacent segments. Here, we show that defective somite patterning underlies the vertebral malformations and altered Notch signaling may contribute to the phenotype. Somites in affected regions are irregular in size and shape, epithelial morphology is disrupted, and anterior-posterior somite patterning is abnormal, reminiscent of somite defects obtained in loss-of-function alleles of Notch signaling pathway components. Expression of Dll1, Dll3, Lfng and Notch1 is altered in rv mutant embryos, and rv and Dll1lacZ, a null allele of the Notch ligand Delta1, genetically interact. Mice double heterozygous for rv and Dll1lacZ, show vertebral defects, and one copy of Dll1lacZ on the homozygous rv background enhances the mutant phenotype and is lethal in the majority of cases. However, fine genetic mapping places rv into an interval on chromosome seven that does not contain a gene encoding a known component of the Notch signaling pathway.
AU  - Beckers, J.
AU  - Schlautmann, N.*
AU  - Gossler, A.*
C1  - 22303
C2  - 21109
SP  - 35-46
TI  - The mouse rib-vertebrae mutation disrupts anterior-posterior somite patterning and genetically interacts with a Delta1 null allele.
JO  - Mech. Dev.
VL  - 95
PY  - 2000
SN  - 0925-4773
ER  - 

TY  - JOUR
AU  - Zarbalis, K.*
AU  - Wurst, W.
C1  - 2784
C2  - 22821
SP  - 165-168
TI  - Expression domains of murine ephrin-A5 in the pituitary and hypothalamus.
JO  - Mech. Dev.
VL  - 93
PY  - 2000
SN  - 0925-4773
ER  - 

TY  - JOUR
AU  - Beckers, J.
AU  - Clark, A.*
AU  - Wünsch, K.
AU  - Hrabě de Angelis, M.
AU  - Gossler, A.*
C1  - 22302
C2  - 21108
SP  - 165-168
TI  - Expression of the mouse Delta1 gene during organogenesis and fetal development.
JO  - Mech. Dev.
VL  - 84
PY  - 1999
SN  - 0925-4773
ER  - 

TY  - JOUR
AU  - Morrison, A.*
AU  - Hodgetts, C.*
AU  - Gossler, A.*
AU  - Hrabě de Angelis, M.
AU  - Lewis, J.*
C1  - 22325
C2  - 21152
SP  - 169-172
TI  - Expression of Delta1 and Serrate1 (Jagged1) in the mouse inner ear.
JO  - Mech. Dev.
VL  - 84
PY  - 1999
SN  - 0925-4773
ER  -