Cadherin-20 expression by motor neurons is regulated by Sonic hedgehog during spinal cord development.

During chicken spinal cord development, cadherin-20 is expressed by motor neurons of the lateral motor column and other cells in the basal and alar plates. To investigate the regulation of cadherin-20 expression, Sonic hedgehog (Shh) signaling was altered in chicken spinal cord and hindbrain by in-vivo electroporation. Our results show that, at an early embryonic stage 12, Shh induces cadherin-20 expression by motor neurons. Later, at stage 24 when the sorting of motor neuron pools begins, cadherin-20 expression is induced in the neural progenitors of the ventricular zone but not in motor neurons. Blockage of Shh signaling inhibits cadherin-20 expression in the motor column. Therefore, cadherin-20 expression in motor neurons is regulated by Shh in a time-dependent manner.