Examining the combinatorial model of motor neuron survival by expression profiling of trophic factors and their receptors in the embryonic Gallus gallus.
During embryogenesis, limb-innervating lateral motor column (LMC) spinal motor neurons (MN) are generated in excess and subsequently nearly half of them die. Many motor neuron survival factors (MnSFs) have been shown to suppress this default programmed cell death (PCD) program through their receptors (MnSFRs), raising the possibility that they are involved in matching specific MNs with their target muscles. Published observations suggest a combinatorial model of MnSF/Rs function, which assumes that during the PCD phase, MNs are expressing combinations of MnSFRs, whereas the limb muscles innervated by these MNs express cognate combinations of MnSFs. We tested this model by expression profiling of MnSFs and their receptors in the avian lumbosacral spinal cord and limb muscles during the peak PCD period. Our findings highlight the complexity of MnSF/Rs function in the control of LMC motor neuron survival.
Gu
Wendy X W
WX
Laboratory of Neural Circuit Development, Institut de recherches cliniques de Montréal (IRCM), QC, Canada.
Kania
Artur
A
D000818:Animals; D016923:Cell Death; D002642:Chick Embryo; D002645:Chickens; D017931:DNA Primers / Q000378:metabolism; D015509:Developmental Biology / Q000379:methods; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D007091:Image Processing, Computer-Assisted; D008024:Ligands; D008161:Lumbosacral Region / Q000196:embryology; D008954:Models, Biological; D009046:Motor Neurons / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013116:Spinal Cord / Q000196:embryology
D017931:DNA Primers; D008024:Ligands