Figure 2

The early/posterior-born Purkinje cells are elongated radially and tangentially in the lateral cerebellum at E12.5 and E13.5. (A-Q) The morphology and orientation of the E10.5-adenovirally labeled nascent Purkinje cells in E12.5 (A-I) and E13.5 (L, O, Q) cerebella are compared with immunoreactivity for Nestin (J, M) (almost identical staining patterns were obtained by using RC2 (not shown)) and Neurofilament (K, N). dn, prospective deep nuclear neurons; RL, rhombic lip. In (I, L), traces of representative cases of E10.5-born nascent Purkinje cells (including cases 1a, 1b, 2, 3, and 4 in this figure, as well as those shown in Additional file 2) are summarized in an illustration of a 'standardized' cerebellar primordium at E12.5 or E13.5. The scale is common in panels (I-N). Note that E10.5-born Purkinje cells seen in an outer zone near the pial surface are tangentially elongated whereas those in deeper regions are more radially elongated. Neurofilament⁺ radial fibers markedly increased between E12.5 and E13.5 and appear to outnumber Nestin⁺ fibers at E13.5. (R) Each tangentially oriented Purkinje cell at E13.5 (Q, R) is polarized with a single thin and long process extended anteriorly (arrowheads) and a thick cytoplasmic part (double blue arrowhead) from which a few thick processes (arrow) are extended posteriorly.