IMB4 is expressed constitutively during ovule development and protein localizes at both cytoplasm and the nucleus. A to D, CLSM of IMB4g-YFP imb4-1 ovule at developmental stage 1-II (A), 2-III (B), 3-I (C), or 3-V (D). D, inset is a stage 3-V ovule at a different angle showing the embryo sac (illustrated by a dotted line). F, funiculus; fm, functional megaspore; ii, inner integument; mmc, megaspore mother cell; oi, outer integument. E, CLSM of IMB4g-YFP imb4-1 root at 4 DAG. Lysotracker red (A to D) or FM4-64 (E) in magenta was used to show cell silhouette. Bars = 10 µm.