RRC ID 12082
Author Prin F, Ng KE, Thaker U, Drescher U, Guthrie S.
Title Ephrin-As play a rhombomere-specific role in trigeminal motor axon projections in the chick embryo.
Journal Dev. Biol.
Abstract In this study, we investigate the possible role of ephrin-Eph signaling in trigeminal motor axon projections. We find that EphA receptors are expressed at higher levels by rhombomere 2 (r2) trigeminal motor neurons than by r3 trigeminal motor neurons in the chick embryo. Mapping of rhombomere-specific axon projections shows that r2 and r3 trigeminal motor neurons project to different muscle targets, including the mandibular adductor and the intermandibularis muscles respectively. Ephrin-A5 is expressed in these muscles, especially in some regions of the intermandibularis muscle, and can cause growth cone collapse of both r2 and r3 motor axons in vitro. We demonstrate that in vivo overexpression of ephrin-A5 in the intermandibularis muscle, or overexpression of dominant-negative EphA receptors in trigeminal motor neurons leads to a reduction in branching of r3-derived motor axons specifically. Overexpression of full-length EphA receptors impairs the formation of r3 projections to the intermandibularis muscle. These findings indicate that ephrins and their Eph receptors play a role in trigeminal motor axon topographic mapping and in rhombomere 3-derived projections in particular.
Volume 279(2)
Pages 402-19
Published 2005-3-15
DOI 10.1016/j.ydbio.2004.12.030
PII S0012-1606(04)00892-9
PMID 15733668
MeSH Animals Body Patterning* Chick Embryo / anatomy & histology Chick Embryo / physiology* Ephrin-A5 / genetics Ephrin-A5 / metabolism* Immunohistochemistry In Situ Hybridization Morphogenesis / physiology Motor Neurons / cytology Motor Neurons / physiology* Muscle, Skeletal / embryology Muscle, Skeletal / innervation* Receptors, Eph Family / genetics Receptors, Eph Family / metabolism Recombinant Fusion Proteins / genetics Recombinant Fusion Proteins / metabolism Signal Transduction / physiology Trigeminal Nerve / cytology Trigeminal Nerve / embryology*
IF 2.936
Times Cited 15
Zebrafish ?