Antibody:	anti-ATF5
Detection system:	Biotinylated secondary antibody/[Strept]avidin coupled to Alexa Fluor 568

Structure	Level	Pattern	Image	Note
TS22: cerebellum ventricular layer	Present		1a , 1aa	The regions of expression correlates with cell proliferation (Mki67+).
TS22: rhombic lip	Present		1a , 1aa	The regions of expression correlates with cell proliferation (Mki67+).
TS22: cerebellum gray matter	Present	Regionally restricted	1aa , 1a	Expressed in a subset of cells in the nascent external granule layer. The regions of expression correlates with cell proliferation (Mki67+).

Structure	Level	Pattern	Image	Note
TS22: cerebellum gray matter	Present	Regionally restricted	1B	Expressed in a few cells in the nascent external granule layer. Expression was less intense than compared to its expression at later embryonic stages.

Structure	Level	Pattern	Image	Note
TS22: cerebellum ventricular layer	Present		1C	Expressed in the nuclei, higher than its expression in the external granule layer.
TS22: rhombic lip	Present		1C	Expressed in the nuclei, higher than its expression in the external granule layer.

Structure	Level	Pattern	Image	Note
TS24: cerebellum external granule cell layer	Present		1e , 1E	More intense and extensive compared to E14.5. Expressed in majority of cells and highest in cells nearest to the rhombic lip. The regions of expression correlates with cell proliferation (Mki67+).
TS24: rhombic lip	Present		1E , 1e	The regions of expression correlates with cell proliferation (Mki67+).

Structure	Level	Pattern	Image	Note
TS24: cerebellum external granule cell layer	Present		1F	Nuclear expression in the majority of the cells.

Structure	Level	Pattern	Image	Note
TS27: cerebellum external granule cell layer	Present	Widespread	2A	Expressed in all lobes. The regions of expression correlates with cell proliferation (Mki67+).
TS27: cerebellar cortex	Present	Regionally restricted	2A	Widely present in all regions of the external granule cell layer, but relatively little expression in the cerebellum outside of the external granule cell layer.

Structure	Level	Pattern	Image	Note
TS28: cerebellum external granule cell layer	Strong		2F , 2H , 2C , 2E	Nuclear expression in the majority of the cells. Majority positive cells were also Mki67+.
TS28: cerebellar cortex	Strong	Regionally restricted	2E , 2C	Strong expression in the external granule cell layer, and in widely dispersed cells outside of the external granule cell layer.

Structure	Level	Pattern	Image	Note
TS28: cerebellum external granule cell layer	Present	Regionally restricted	3A , 3C , 3D , 3F	Specifically in the outer external granule layer, where the proliferating cerebellar granule neuron progenitor cells are found.
TS28: cerebellar cortex	Present	Regionally restricted	3A , 3C	Expression in the external granule layer is lower than at P6 and very few proliferating cells are found outside of external granule layer.

Structure	Level	Pattern	Image	Note
TS28: cerebellum external granule cell layer	Present		3H	Decreased expression and only in a relatively few proliferating cells. Little or no expression outside of the external granule cell layer.

Structure	Level	Pattern	Image	Note
TS28: cerebellum external granule cell layer	Strong		S1C , S1A	Highly expressed in cerebellar granule neuron progenitor cells.
TS28: cerebellar cortex	Strong	Regionally restricted	S1A , S1C	Highly expressed in the external granule cell layer. No co-staining with Tubb3.

Structure	Level	Pattern	Image	Note
TS28: cerebellum external granule cell layer	Present		S1D , S1F	Specifically in the outer external granule layer. No co-staining with Rbfox3.

Structure	Level	Pattern	Image	Note
TS25: cerebellum external granule cell layer	Present			Expressed in majority of cells and highest in cells nearest to the rhombic lip, similar as in E16.5. The regions of expression correlates with cell proliferation (Mki67+).
TS25: rhombic lip	Present			The regions of expression correlates with cell proliferation (Mki67+).

Structure	Level	Pattern	Image	Note
TS28: cerebellum internal granule cell layer	Absent
TS28: cerebellum molecular layer	Absent