Probe:	semB probe2
Probe preparation:	labelled with S35 RNA
Visualized with:	Autoradiography

Structure	Level	Pattern	Image	Note
TS17: hindbrain marginal layer	Weak	Regionally restricted	1A	Weak expression in marginal zone of post-otic hindbrain. Expression highest in ventral half.

Structure	Level	Pattern	Image	Note
TS17: future spinal cord	Absent			No expression in thoracic spinal cord at this stage.

Structure	Level	Pattern	Image	Note
TS19: future spinal cord	Present	Regionally restricted	1B	Expression apparent in thoracic spinal cord.

Structure	Level	Pattern	Image	Note
TS20: spinal cord marginal layer	Present	Widespread	2B	Expression throughout marginal zone.

Structure	Level	Pattern	Image	Note
TS23: spinal cord thoracic region	Present	Widespread	4B	Expression thoughout spinal cord with the exception of the superficial dorsal horn.
TS23: spinal cord dorsal horn	Absent		4B

Structure	Level	Pattern	Image	Note
TS20: brain	Present	Widespread		Expression throughout brain in most postmitotic neurons, with the exception of the telencephalon.
TS20: telencephalon	Absent

Structure	Level	Pattern	Image	Note
TS23: brain	Present	Uniform	6B	Authors report expression was distributed more uniformly.
TS23: cerebral cortex	Weak		6B	Low levels of expression in immature cortex.