Formation and spatial arrangement of non-cortical telencephalic tissues.

<p>(A) Expression pattern of markers for cortex, cortical hem, and choroid plexus on embryonic day 12 (E12). (B) Hem-derived Cajal-Retzius cells expressing p73 on E12. (C–D) The hem-like tissues (Lmx1a⁺, Otx2⁺) formed adjacent to cortical tissues (Foxg1::venus⁺) in culture. The hem-like tissues also contained p73⁺ cells. (E) Schematic for SFEBq/gfCDM+IwL culture with Shh treatment. (F–H) <i>In vivo</i> expression of pallial and subpallial markers on E12. Cortical markers (Pax6, Ngn2, Tbr1), LGE markers (Gsh2, Dlx2, Mash1, Gad65), and MGE markers (Nkx2.1, Dlx2, Mash1, Gad65). (I) Schematic of the marker expression pattern. (J–M) Shh treatment induced the formation of subpallial tissues. LGE tissues (Gsh2⁺, Dlx2⁺, Mash1⁺) were located between cortical tissues (Pax6⁺, Ngn2⁺, Tbr1⁺) and MGE tissues (Nkx2.1⁺, Dlx2⁺, Mash1⁺). Arrowheads indicate a transition between pallial and subpallial tissues. (N) Expression of Gsh2::venus in thickened NE tissue on day 14. (O–Q) Immunostaing of Gsh2::venus⁺ NE on day 14. Immunostaining for Gsh2 (O), Mash1 (P) and Gad67/Dlx2 (Q). chp, choroid plexus; LGE, lateral ganglionic eminence; LV, lateral ventricle; MGE, medial ganglionic eminence; PSB, pallial-subpallial boundary; Th, thalamus. Scale bars, 100 µm (A–D,J–M,O–Q); 200 µm (F–H,N).