Fig. 8. Expression of the root apical meristem marker genes in the obe1 obe2 double mutant. (A,F) QC46 expression in the central root cap of wild-type (A) and obe1 obe2 (F) seedlings. (B,G) QC46 expression in wild-type (B) and obe1 obe2 (G) heart stage embryos. (C-E,H-R) In situ hybridization with WOX5 (C,D,H,I), MP (E,J), PLT1 (K,L,O,P) and SCR (M,N,Q,R) antisense probes hybridized to embryos from self-fertilized OBE1/obe1 obe2/obe2 plant. Longitudinal sections of in situ hybridization specimens are shown. (C,H) Early globular stage embryos. (D,I,L,P) Late globular stage embryos. (E,J,N,R) Heart stage embryos. (K,O) Eight-cell stage embryos. (M,Q) Globular stage embryos. About one quarter of the embryos from self-fertilized OBE1/obe1 obe2/obe2 plants failed to express WOX5 (H,I), PLT1 (O,P) or SCR (Q,R), while the remaining three-quarters of the embryos exhibited wild-type-like expression of the above genes. By contrast, MP expression was detected in all embryos (J). Scale bars: 25 µm in A-J,L-N,P-R; 10 µm in K,O.