Figure 8
From: Pattern and process in the evolution of the sole dioecious member of Brassicaceae
Confocal microscopy of longitudinal sections of anther sacs from hermaphroditic, male and female flowers of Lepidium treated with TUNEL assay and controls. (A-F, K-L) Hermaphroditic L. tenuicaule. (G-J) Carpellate L. sisymbrioides. (M-R) Staminate L. sisymbrioides. (A, C, E, G, I, K, M, O, Q) Anthers under DAPI excitation and emission. (B, D, F, H, J, L, N, P, R) Anthers under fluorescein excitation and emission. (A-D, M-P) Mature, functional anther sacs at stage 13. (G-J) Mature anther sacs, aborted at stage 9. (E-F, Q-R) Functional anther sacs forming tetrads, tapetum, and endothecium at stage 9. (A-B, G-H, M-N) Negative controls (-), anther sacs untreated: cell walls, nuclei, and pollen autofluoresce. (C-F, I-J, O-R) TUNEL assay. Red arrows point to an exemplary nucleus from each tissue layer that exhibits above-background fluorescein signal. (K-L) Positive control (+), anther sac treated with DNase I: nuclei in endothecium show strong fluorescein emission in L compared to B. Scale bar = 25 μm. En, endothecium; Ep, epidermis; N, nucleus; P, pollen; Ta, tapetum; Te, tetrads.