Specification of astrocytes by bHLH protein SCL in a restricted region of the neural tube

@article{Muroyama2005SpecificationOA,
  title={Specification of astrocytes by bHLH protein SCL in a restricted region of the neural tube},
  author={Yuko Muroyama and Yuko Fujiwara and Stuart H. Orkin and David H. Rowitch},
  journal={Nature},
  year={2005},
  volume={438},
  pages={360-363}
}
Astrocytes are the most abundant and functionally diverse glial population in the vertebrate central nervous system (CNS). However, the mechanisms underlying astrocyte specification are poorly understood. It is well established that cellular diversification of neurons in the embryo is generated by position-dependent extrinsic signals and combinatorial interactions of transcription factors that direct specific cell fates by suppressing alternative fates. It is unknown whether a comparable… 
Dbx1 controls the development of astrocytes of the intermediate spinal cord by modulating Notch signaling
TLDR
It is demonstrated that a restricted pool of progenitors in the mouse spinal cord, expressing the transcription factor Dbx1, produces a subset of astrocytes, in addition to interneurons, and that progenitor transcriptional programs highly influence glial fate and are instrumental in creatingAstrocyte diversity.
Foxn4: A multi-faceted transcriptional regulator of cell fates in vertebrate development
TLDR
In development of non-neural tissues, Foxn4 plays an essential role in the specification of the atrioventricular canal and is indirectly required for patterning the distal airway during lung development.
PAX6 CONTROLS ASTROCYTE POSITIONAL IDENTITY IN THE SPINAL CORD
Astrocytes constitute the most abundant cell type in the CNS, and play diverse functional roles, but the ontogenetic origins of this phenotypic diversity are poorly understood. We have investigated
Regulation of spinal interneuron development by the Olig-related protein Bhlhb5 and Notch signaling
TLDR
It is demonstrated that the Olig-related transcription factor Bhlhb5 (recently renamed Bhlhe22) plays two central roles in this process: transforming the spatial information established by morphogen signaling into local cell-cell interactions associated with Notch signaling that control the progression of neurogenesis and extend neuronal diversity within the developing spinal cord.
Association of astrocytes with neurons and astrocytes derived from distinct progenitor domains in the subpallium
TLDR
Although neurons and astrocytes arelabeled in various regions, only neurons are labeled in the neocortex, hippocampus and olfactory bulb, and forebrain astracytes can associate with neurons as well as astroCytes derived from a distinct PD.
Regulated temporal-spatial astrocyte precursor cell proliferation involves BRAF signalling in mammalian spinal cord
TLDR
Aldh1L1-GFP is used to identify two morphologically distinct types of proliferative astrocyte precursors: radial glia in the ventricular zone and a second cell type the authors call an ‘intermediate astroCyte precursor’ (IAP) located in the mantle region of the spinal cord.
The spinal cord contains positionally distinct astrocyte subtypes whose identities are specified by a homeodomain transcriptional code
Astrocytes constitute the most abundant cell type in the CNS, and play diverse functional roles, but the ontogenetic origins of this phenotypic diversity are poorly understood. We have investigated
A Critical Cell-Intrinsic Role for Serum Response Factor in Glial Specification in the CNS
TLDR
This work shows that deletion of the stimulus-dependent transcription factor, serum response factor (SRF), in neural precursor cells (NPCs) results in nearly 60% loss in astrocytes and 50% Loss in oligodendrocyte precursors at birth, and suggests that SRF plays a critical cell-autonomous role in NPCs to regulate astroCyte and oligod endocrine specification in vivo and in vitro.
Combinatorial actions of patterning and HLH transcription factors in the spatiotemporal control of neurogenesis and gliogenesis in the developing spinal cord
TLDR
A molecular code model is proposed whereby the combinatorial actions of two classes of transcription factors coordinately regulate the domain-specific temporal sequence of neurogenesis and gliogenesis in the developing spinal cord.
...
...

References

SHOWING 1-10 OF 31 REFERENCES
Coexpression of SCL and GATA3 in the V2 interneurons of the developing mouse spinal cord
TLDR
Investigation of a possible role for the Stem Cell Leukemia (SCL) gene, a basic helix‐loop‐helix (bHLH) transcription factor gene, in the specification of a population of neural cells in the ventral neural tube revealed that SCL is transiently expressed within the V2 postmitotic domain of the developing mouse spinal cord.
The Sox9 transcription factor determines glial fate choice in the developing spinal cord.
TLDR
Stem cells apparently fail to switch from neurogenesis to gliogenesis in at least two domains of the ventricular zone, indicating that Sox9 is a major molecular component of the neuron-glia switch in the developing spinal cord.
Glial specification in the vertebrate neural tube
TLDR
Understanding of the mechanisms that underlie the specification of precursors for two key macroglial subtypes in the embryo are highlighted, including emergence from localized regions of the neural tube, and involvement of common signalling pathways and downstream transcription factors.
Specification of hematopoietic and vascular development by the bHLH transcription factor SCL without direct DNA binding.
TLDR
These findings establish DNA-binding-independent functions of SCL critical for transcriptional specification, and should encourage reassessment of presumed requirements for direct DNA binding by other transcription factors during initiation of developmental programs.
GATA2 is required for the generation of V2 interneurons.
TLDR
It is shown here that Gata2 is expressed in the ventral spinal cord exclusively in newly generated V2 interneurons, suggesting that GATA2 might be required for the generation of this discrete neuronal population.
The SCL gene specifies haemangioblast development from early mesoderm
TLDR
These results provide the first evidence that SCL specifies formation of haemangioblasts, the proposed common precursor of blood and endothelial lineages, and underline the striking similarities between the role of SCL in haematopoiesis/vasculogenesis and the function of other bHLH proteins in muscle and neural development.
GATA proteins identify a novel ventral interneuron subclass in the developing chick spinal cord.
TLDR
The findings strongly suggest an important role for GATA2 and GATA3 proteins in the establishment of a distinct ventral interneuron subpopulation in the developing chick spinal cord.
Fgfr3 expression by astrocytes and their precursors: evidence that astrocytes and oligodendrocytes originate in distinct neuroepithelial domains
TLDR
It is found that mice with a targeted deletion in the Fgfr3 locus strongly upregulate Gfap in grey matter (protoplasmic) astrocytes, implying that signalling through F gfr3 normally represses GfAP expression in vivo.
...
...