Non-overlapping expression of Olig3 and Olig2 in the embryonic neural tube

Abstract

Olig family is a novel sub-family of basic helix-loop-helix transcription factors recently identified. Olig1 and Olig2 were first reported to promote oligodendrocyte differentiation, and later Olig2 was reported to be involved in motoneuron specification as well. Olig3 was isolated as a third member of Olig family, but its precise expression pattern is poorly understood. Here, we describe detailed Olig3 expression analyses in the neural tube of embryonic mice. Olig3 was first detected in the dorsal neural tube from the midbrain/hindbrain boundary to the spinal cord. In E11.5 spinal cord, Olig3 was transiently expressed in the lateral margin of the subventricular zone as three ventral clusters at the level of the p3, p2 and p0 domains, as well as in the dorsal neural tube. Olig3 was co-expressed with Nkx2.2 in the lateral margin of the p3 domain. In forebrain, Olig3 was expressed in the dorsal thalamus while Olig2 was complementarily expressed in the ventral thalamus with an adjacent boundary at E12.5. Olig3 is specifically and transiently expressed in different types of progenitors of embryonic central nervous system and then disappears in the course of development.

The basic helix–loop–helix olig3 establishes the neural plate boundary of the trunk and is necessary for development of the dorsal spinal cord

“…By in situ hybridization, olig3 transcripts are first detected at the shield stage in a stripe of the deep cell layer (not shown). This early and wide expression is peculiar to olig3 and is not observed for the other members of the olig gene family (8,9). At the tail bud stage (Fig.…”

“…The Neurogenin (Ngn) subfamily of bHLH is critical to establish the neurogenic program and maintain the Delta͞Notch regulatory feedback that creates differences within the nervous system (3)(4)(5). Recently, a previously unrecognized vertebrate-specific group of bHLH has been shown to participate in neural fate decisions mediated by Delta͞Notch signaling: the known members of this family are olig1, olig2, and olig3 (6)(7)(8)(9). The discovery that, in mice, chickens, and zebrafish, olig2 is necessary for the differentiation of motoneurons and oligodendrocytes from a ventral population of multipotent neural precursors raised the crucial issue of whether other neuroepithelial domains in the ventral or dorsal spinal cord can switch from neuron to glial cell production: for example, from neurons to astrocytes (6)(7)(8).…”

“…The discovery that, in mice, chickens, and zebrafish, olig2 is necessary for the differentiation of motoneurons and oligodendrocytes from a ventral population of multipotent neural precursors raised the crucial issue of whether other neuroepithelial domains in the ventral or dorsal spinal cord can switch from neuron to glial cell production: for example, from neurons to astrocytes (6)(7)(8). In mice, the expression domains of olig1 and olig2 are partially overlapped and distinct from that of olig3 (9). Because the function of olig3 has not been determined yet, we have isolated and analyzed the zebrafish olig3 gene.…”

Regulatory pathways linking progenitor patterning, cell fates and neurogenesis in the ventral neural tube

“…An examination of the Olig2-related bHLH protein Olig3 in the dorsal spinal cord shows that Olig3 plays an essential role in the specification of different classes of dorsal interneurons and is additionally required for the patterned expression of proneural bHLH proteins within dorsal progenitors (Muller et al 2005). Intriguingly, Olig3 appears to be expressed by several groups of cells in the ventral spinal cord (Takebayashi et al 2002b), raising the possibility that the function of the Olig family of bHLH proteins in coordinating cell-fate choices and neurogenesis may be widespread.…”

Estudos de associação genética no transtorno obsessivo-compulsivo

“…The transcription factor of the oligodendrocyte lineage 2 (OLIG2) is involved in myelination and neurogenesis and is essential in regulating the development of cells producing white substance (myelin) 106 111 . Genes related to white matter in OCD have been studied little and his findings are interesting.…”