Fig. 4.
In situ BnPME expression by FISH during gametophytic development and microspore embryogenesis. a, b, c are the same structures as in a’, b’, c’. a, b, c DIC images (Differential Interference Contrast, Nomarsky). a’, b’, c’, d, e, f Confocal merged images of fluorescence provided by DAPI staining of nuclei (in blue) and fluorescence in situ BnPME hybridization signal (in green). a, a’ Vacuolated microspore. b, b’ Gametophytic development, in vivo, bicellular pollen. c, c’, d, e, f Microspore embryogenesis, in vitro. c-c’ Proembryo. d Globular embryo. (Inset in d) Globular embryo stained with I2IK for starch. e Detail of globular embryo peripheral cells at higher magnification. f FISH control with the sense probe in globular embryo. Ex: exine, N: nucleus, V: vacuole, g: generative nucleus, v: vegetative nucleus. Bars: a, a’, b, b’, c, c, 10 μm; d, e, f, 20 μm