Neurotrophin 3 stimulates the differentiation of motoneurons from avian neural tube progenitor cells.
Neurotrophin 3 (NT-3) promotes differentiation of neural tube progenitors into motoneurons expressing the BEN/SC1 and islet-1 epitopes. A 1.75- to 6.7-fold increase in BEN-positive motoneurons was obtained when quail neural tube cells were cultured with NT-3 at 0.1-10 ng/ml, respectively. In contrast, the overall number of cells, as well as the proportion of motoneurons that developed from cycling precursors, did not change. Addition of NT-3 at 1 ng/ml to cells obtained from ventral half-neural tubes promoted a 2.5-fold stimulation in motoneuron number, confirming the specificity of the effect. Moreover, NT-3 had no significant effect on survival of differentiated avian motoneurons. The distribution of trkC mRNA, which encodes the high-affinity receptor for NT-3, is consistent with these findings. trkC expression is homogeneous in the embryonic day 2 (E2) neural tube, becomes restricted to the mantle layer on E3, where differentiation occurs, and disappears from the ventral third of the E4-E5 spinal cord right before the onset of normal motoneuron death. These results suggest that NT-3 and trkC regulate early neurogenesis in the avian central nervous system.
Averbuch-Heller
L
L
Department of Anatomy and Embryology, Hebrew University-Hadassah Medical School, Jerusalem, Israel.
Pruginin
M
M
Kahane
N
N
Tsoulfas
P
P
Parada
L
L
Rosenthal
A
A
Kalcheim
C
C
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002454:Cell Differentiation / Q000187:drug effects; D003370:Coturnix; D017931:DNA Primers / Q000737:chemistry; D015870:Gene Expression; D008969:Molecular Sequence Data; D009046:Motor Neurons / Q000166:cytology*; D009414:Nerve Growth Factors / Q000494:pharmacology*; D009420:Nervous System / Q000196:embryology*; D020933:Neurotrophin 3; D012333:RNA, Messenger / Q000235:genetics; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics; D020812:Receptor, trkC; D017978:Receptors, Growth Factor / Q000235:genetics
D017931:DNA Primers; D009414:Nerve Growth Factors; D020933:Neurotrophin 3; D012333:RNA, Messenger; D017978:Receptors, Growth Factor; D020794:Receptor Protein-Tyrosine Kinases; D020812:Receptor, trkC