Figure 1.

Rice gametes expressing the H2B-GFP, H2B-RFP, or SUN2-GFP fusion protein. A and B, An egg cell isolated from transgenic rice expressing H2B-GFP under control of the ubiquitin promoter visualized with bright-field (A) and fluorescence (B) microscopy. The arrowheads indicate nucleoli. C and D, An egg cell isolated from transgenic rice expressing H2B-RFP under control of the DD45 promoter visualized with bright-field (C) and fluorescence (D) microscopy. The arrowheads indicate nucleoli. E and F, A pollen grain expressing H2B-GFP under control of the ubiquitin promoter visualized with bright-field (E) and fluorescence (F) microscopy. Arrowheads and the arrow indicate sperm and vegetative nuclei, respectively. G and H, A pollen grain expressing H2B-GFP releasing its content in mannitol solution visualized with bright-field (G) and fluorescence (H) microscopy. Arrowheads indicate sperm cells, and the arrow indicates a possible vegetative nucleus. I to K, An egg cell expressing SUN2-GFP under control of the ubiquitin promoter visualized with fluorescence (I) and bright-field (J) microscopy. K contains the merged images of I and J. L to N, A pollen grain expressing SUN2-GFP releasing its content in mannitol solution (L). Two released sperm cells enclosed within the square in L were visualized with fluorescence microscopy (M). N contains the merged bright-field and fluorescent images. Bars = 20 μm. [See online article for color version of this figure.]