Fig. 5: Callose deposition and phenotypes in ovules expressing GLUC.
From: Germline β−1,3-glucan deposits are required for female gametogenesis in Arabidopsis thaliana
a, c, e In wild-type, decolourised aniline blue (DAB) stains punctate callose deposits in the wall of the MMC as it expands from stages 2-II to 2-III. These deposits accumulate over time and become large aggregates that encompass much of the MMC wall. b, d, f In pKNU:GLUC ovules, punctate callose deposits are less obvious in the MMC wall and the overall pattern is more diffuse compared to wild-type. Despite this, large aggregates are detected at the cell periphery at stage 2-III prior to the initiation of meiosis. g Cleared wild-type ovule containing a wild-type mature embryo sac at anthesis. h Example of a wild-type-like embryo sac from a pKNU:GLUC line. i Aborted FG1 embryo sac (where the functional megaspore has aborted gametogenesis at FG1 with a central nucleus and vacuoles at both poles) in a pKNU:GLUC ovule. j Aborted FG1 embryo sac in a pWUS:GLUC ovule. Staging according to Schneitz et al.5: (a, b) stage 2-I, (c–f) stage 2-II to 2-III. Experiments were repeated on 6 independent occasions with similar results. Representative micrographs are shown. Scale bars = 20 µm. aFG1 aborted female gametophyte, ccn central cell nucleus, ecn egg cell nucleus, DAB decolourised aniline blue, FGm mature female gametophyte, fu funiculus, ii inner integument, mmc megaspore mother cell, ne nucellar epidermis, oi outer integument, sc seed coat, sy synergid.
