Corpus ID: 35612286

Role of Lmx1b and Wnt1 in mesencephalon and metencephalon development.

@article{Matsunaga2002RoleOL,
  title={Role of Lmx1b and Wnt1 in mesencephalon and metencephalon development.},
  author={Eiji Matsunaga and Tatsuya Katahira and Harukazu Nakamura},
  journal={Development},
  year={2002},
  volume={129 22},
  pages={
          5269-77
        }
}
The isthmus is the organizing center for the tectum and cerebellum. Fgf8 and Wnt1 are secreted molecules expressed around the isthmus. The function of Fgf8 has been well analyzed, and now accepted as the most important organizing signal. Involvement of Wnt1 in the isthmic organizing activity was suggested by analysis of Wnt1 knockout mice. But its role in isthmic organizing activity is still obscure. Recently, it has been shown that Lmx1b is expressed in the isthmic region and that it may… Expand
Lmx1b is essential for Fgf8 and Wnt1 expression in the isthmic organizer during tectum and cerebellum development in mice
TLDR
The results indicate that Lmx1b plays an essential role in the development of the tectum and cerebellum by regulating expression of Fgf8, Wnt1 and several isthmus-related transcription factors in the MHB, and is a crucial component of a cross-regulatory network required for the induction activity of the isthmic organizer in theMHB. Expand
Zebrafish Lmx1b.1 and Lmx1b.2 are required for maintenance of the isthmic organizer
TLDR
It is proposed that Lmx1b.1- and Lmx 1b.2-mediated regulation of wnt1,wnt3a, wnt10b, pax8 and fgf8 maintains cell survival in the isthmocerebellar region. Expand
Isthmus organizer for midbrain and hindbrain development
TLDR
A strong Fgf8 signal activates the Ras-ERK signaling pathway, which in turn activates Irx2 in a rostrodorsal part of the hindbrain, and forces this tissue to differentiate into cerebellum. Expand
The duration of Fgf8 isthmic organizer expression is key to patterning different tectal-isthmo-cerebellum structures
TLDR
It is found that cell death cannot be the main factor accounting for the loss of brain structures near the isthmus, and instead it is demonstrated that tissue transformation underlies the observed phenotypes. Expand
Isthmus organizer and regionalization of the mesencephalon and metencephalon.
The brain vesicles that are formed at an early stage of neural development are the fundamentals of the brain plan. Heterotopic transplantation revealed that the diencephalon could change its fateExpand
Regulation of isthmic Fgf8 signal by sprouty2
TLDR
The results indicate that Fgf8 activates the Ras-ERK signaling pathway to differentiate the cerebellum, and that the hyper- or hypo-signaling of this pathway affects the fate of the brain vesicles. Expand
Wnt1-lmx1a forms a novel autoregulatory loop and controls midbrain dopaminergic differentiation synergistically with the SHH-FoxA2 pathway.
TLDR
Two regulatory loops critically link extrinsic signals to cell-intrinsic factors and cooperatively regulate mDA neuron development and coactivation of both Wnt1 and SHH pathways by exogenous expression of Lmx1a, Otx2, and FoxA2 synergistically enhanced the differentiation of ESCs to mDA neurons. Expand
Overlapping Function of Lmx1a and Lmx1b in Anterior Hindbrain Roof Plate Formation and Cerebellar Growth
TLDR
Phenotypic analysis of single and compound conditional mutants confirmed overlapping roles for Lmx1 genes in regulating hindbrain roof plate formation and growth and also revealed roles in regulating adjacent cerebellar morphogenesis, providing the first evidence of overlapping function of the LMX1 genes during embryonic CNS development. Expand
Lmx1b is essential for survival of periocular mesenchymal cells and influences Fgf-mediated retinal patterning in zebrafish.
TLDR
By blocking the death of the periocular mesenchyme in Lmx1b morphants, optic vesicle morphogenesis is largely restored and the proposed zebrafish lMX1b.1 and lmx1 b.2 promote the survival of periacular mesenchymal cells that influence multiple signaling events required for proper ocular development. Expand
Convergent Wnt and FGF signaling at the gastrula stage induce the formation of the isthmic organizer
TLDR
Evidence is provided that convergent Wnt and FGF signaling at the gastrula stage are required to generate the complex polarized pattern of cells characteristic of the IsO, and that Wntand FGF signals in combination are sufficient to reconstruct, in naïve forebrain cells, an IsO-like structure that exhibits an organizing activity that mimics the endogenous IsO when transplanted into the diencephalon of chick embryos. Expand
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References

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TLDR
It is reported that the transcription factor Lmx1b is expressed and functions in a distinct region of the IsO, and it is suggested that LMX1b and Wnt1 normally function in concert to affect IsO morphogenesis. Expand
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TLDR
The results all support the working hypothesis that the strong Fgf8 signal induces the neural tissue around the isthmus to differentiate into the cerebellum. Expand
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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