Fig. 1.
Histochemical localization of GUS activity in anthers of pP5CS1:GUS and pP5CS2:GUS transgenic Arabidopsis. Inflorescences of pP5CS1:GUS (a-g) and pP5CS2:GUS (h-n) transgenic plants were infiltrated with X-Gluc solution, stained overnight, fixed and cleared for microscopic analysis. a, h Whole-mount inflorescences with buds and flowers at various developmental stages showing GUS activity almost exclusively in anthers. b-g and i-n Transverse sections of anthers at different developmental stages: b, i Stage 8 with pre-meiotic microspore mother cells; c, j Stage 9 with microspore tetrads; d, k Stage 10 with strong activity of both pP5CS1:GUS and pP5CS2:GUS after tetrad separation; e, l Stage 11 with fully developed exine and degenerating tapetum; f, m Stage 12 with septum degeneration and g, n stage 13 with mature pollen at anther dehiscence. Almost no GUS staining was detected in any sporophytic anther tissue. All scale bars = 20 μm