Evidence for the differential regulation of Nkx-6.1 expression in the ventral spinal cord and foregut by Shh-dependent and -independent mechanisms.
The Nkx-6.1 homeodomain transcription factor was previously shown to be expressed in ventral neural progenitor cells and subsequently subsets of unidentified motor neurons during early neural development. In this study, we identify a specific subpopulation of motor neurons, the median half of the lateral motor neuron column (LMCm), that retain a strong expression of Nkx-6.1. In addition, we report novel patterns of Nkx-6.1 expression in several mesenchymal tissues surrounding Sonic hedgehog (Shh)-expressing cells, including ventral spinal meninges, esophageal mesenchyme, and dorsal tracheal mesenchyme. Whereas Shh signaling is required for Nkx-6.1 expression in the ventral neural tube and spinal meninges, an Shh-independent pathway appears to operate in regulating Nkx-6.1 expression in the foregut. The persistent and robust expression of Nkx-6.1 in motor neurons and mesenchymal cells suggests an important role for Nkx-6.1 in controlling cell fate specification and differentiation. genesis 27:6-11, 2000.
Cai
J
J
Xu
X
X
Yin
H
H
Wu
R
R
Modderman
G
G
Chen
Y
Y
Jensen
J
J
Hui
C C
CC
Qiu
M
M
D000818:Animals; D002642:Chick Embryo; D004947:Esophagus / Q000196:embryology* / Q000378:metabolism; D005136:Eye Proteins / Q000096:biosynthesis; D018507:Gene Expression Regulation, Developmental; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins / Q000096:biosynthesis / Q000235:genetics*; D060850:LIM-Homeodomain Proteins; D009046:Motor Neurons / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000096:biosynthesis; D011506:Proteins / Q000378:metabolism*; D013116:Spinal Cord / Q000196:embryology* / Q000378:metabolism; D015534:Trans-Activators; D014157:Transcription Factors
D005136:Eye Proteins; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins; C491186:LHX5 protein, human; D060850:LIM-Homeodomain Proteins; D009419:Nerve Tissue Proteins; C491328:Nkx6-1 protein, mouse; D011506:Proteins; C509239:SHH protein, human; D015534:Trans-Activators; D014157:Transcription Factors; C063843:insulin gene enhancer binding protein Isl-1