Fig. 5.

gct and cct mutants uncouple pattern formation, growth and morphogenesis in early embryos. (A,B) Wild-type and gct embryos at the octant stage (A), and wild-type and cct embryos at the dermatogen stage (B). The plane of the first division is marked with an arrow, the embryo is marked with a bracket and the suspensor is marked with a dashed line. (C) Wild-type globular stage embryo. (D) Weak (left) and strong (right) globular stage gct embryos. (E) Globular stage cct embryos show similar defects. In B-E, the cells of the upper tier and their derivatives (u), the lower tier and their derivatives (t), extra tiers in gct and cct (x) and the uppermost cell of the suspensor and its derivatives (asterisks) are labeled. (F) Wild-type early heart stage embryo. (G) Early heart stage gct embryos with two (left) or one (middle) small cotyledon primordia, or with random divisions throughout the embryo (right). (H) Similar phenotypes are seen in early heart stage cct embryos. (I-K) At the wild-type late heart stage (I), gct (J, left) and cct (K, left) embryos with two cotyledon primordia, and gct (J, right) and cct (K, right) embryos with random divisions throughout the embryo. In F-K, the shoot apical meristem, root apical meristem, and vascular primordia (vp) are indicated with lines, and the cotyledon primordia with arrowheads. (L) Cell numbers in medial sections of wild-type, gct and cct embryos at the early globular, late globular, early heart and late heart stages. Standard deviation is shown at top of bars in L (n≥8). All images in A-K are tracings of cleared embryos. At each developmental stage, the percentage of each phenotypic class of mutant embryos in siliques of heterozygous plants is shown, along with the total number of embryos scored. All images shown at equal magnification. Scale bar: 10 μm.