Figure 4From: The MYST histone acetyltransferases are essential for gametophyte development in ArabidopsisAnalysis of gametophyte development in ham sesquimutants. (A-F) Analysis of pollen development by DAPI staining. Pollen grains were released from anthers, stained with DAPI, and visualized under a light microscope equipped with a UV fluorescent filter. At uni-nucleate stage, microspores of wild-type (A) and HAM1/ham1-1; ham2/ham2 plants (D) were indistinguishable. In contrast to wild-type microspores (B and C), HAM1/ham1-1; ham2/ham2 plants contain approximately one-half of arrested microspores (arrows) at the bicellular (E) and tricellular pollen stages (F). Bars: 10 μm. (G-J) Cleared whole mounts of wild-type and ham sesquimutant ovules. Mature ovules at stage G7 of wild-type (G) and HAM1/ham1-1; ham2/ham2 mutant (H). Bars: 40 μm. Images I and J are enlargements of boxed sections in G and H respectively. Bars: 20 μm. (I) Magnified section shows the presence of central cell nucleus, two synergid nuclei and the egg cell nucleus in wild-type ovule. (J) An ovule from ham sesquimutant at the same stage showing the presence of only one nucleus (white arrow). No other nuclei were visualized at other focal planes.Back to article page