Effects of changes in pollen ploidy/size on pollen aperture patterns in the <i>mcr</i> and <i>dnt</i> mutants.

(A-B’) Diploid mcr pollen forms three apertures (arrowheads), independently of the meiotic product arrangement. (A-A’) Front and back views of the 2n mcr pollen produced by a 4n plant through a tetrad formation. (B-B’) Front and back views of the 2n mcr osd1 pollen produced through a dyad formation. (C-C’) Diploid pollen of dnt osd1, similar to the haploid dnt pollen, usually has two round apertures (arrowheads). See also S7 Video. (D) INP1-YFP forms three longitudinal lines (arrowheads) in diploid mcr osd1 dyads. A 3D reconstruction of a mcr osd1 INP1-YFP dyad is shown. See also S8 Video. (E) INP1-YFP forms puncta at the proximal and distal poles of microspores in diploid dnt osd1 dyads. A 3D reconstruction of a dnt osd1 INP1-YFP dyad is shown. See also S9 Video. (F-F’) Increase of pollen ploidy in mcr osd1 to 4n most commonly leads to the formation of a ring-like aperture on one side of the pollen grain (F, arrowhead) and one or several hole-like apertures (F’, arrowhead) on the other side. (G-G’) Increase of pollen ploidy in dnt osd1 to 4n usually increases the number of round apertures to more than two. (H-H”’) The ring-like apertures (arrowheads) in the 4n mcr osd1 dyads are located on the distal end of each microspore, thus placing the hole-like apertures at the proximal end, near the intersporal callose wall (black arrows). Shown are different views of a 3D reconstruction of a late-stage dyad (H-H”) and a maximum intensity projection of a confocal z-stack of the same dyad (H”’) See also S10 Video. Scale bars = 10 μm.