Vertebrate Embryonic Patterning 5

Neural Crest

Neural Crest Cells

Neural Crest DerivativesTwo major divisionsCranialTrunk

PNS EndocrineMelanocytesFacial CartilageConnective Tissue

Trunk Neural Crest

Neural Crest Cells Stain Positive for ECM Protein HNK-1

RhoB

HNK-1

Migratory Pathways of Neural Crestephrins expressed in posterior

compartment of somite

Ephrin – Eph RTK Pathway Regulates NC Migration Through/Over Somites

Eph RTKs and ephrins appear to regulate boundary formation and cell-cell interactions in many regions of the embryo

Ephrins Repulse Axon Growth

Signals from the Floorplate Induce Axon Migration

Netrin Induces Commissural Axon Growth

Semaphorins Repulse Axons

Axonal Guidance in Invertebrates

Eph RTK & Ephrins Regulate Retinotectal

Patterning