A Species-Specific Cluster of Defensin-Like Genes Encodes Diffusible Pollen Tube Attractants in Arabidopsis
Figure 3
Expression pattern and localization of CRP810_1 peptides.
(A) Real-time qRT-PCR analysis of CRP810_1 genes (CRP810_1.1 to _1.6) in seedlings 10 d after germination (Sd), stems (St), leaves (Le), open flowers without the pistil (Fl), pistils (Pi), and siliques 2 d after pollination (Si). Relative quantities are expression levels relative to that in the pistil. Each expression level was normalized to that of ACT2. The data are the means and standard errors of three independent samples. (B) Absolute gene expression levels of CRP810_1 genes. Absolute quantity represents the copy number of cDNA per that of MYB98 cDNA. The means and standard deviations of three independent experiments are shown. (C) Schematic of the ovule (left) and part of the synergid cell (sy) (right) in A. thaliana. The filiform apparatus (fa) is formed by the thickened cell walls of the synergid cells. f, funiculus; mp, micropyle. (D) Confocal laser scanning microscopic (CLSM) image of a pCRP810_1.2::GFP ovule. Scale bar, 20 µm. (E) Fluorescence microscopic images of pCRP810_1::CRP810_1-GFP ovules. Scale bar, 20 µm. (F) A CLSM image of an ovule after immunostaining with anti-CRP810_1.2 antibodies. Green Alexa Fluor fluorescence (for CRP810_1 peptides) was observed at the micropyle and funicular surface. Magenta indicates autofluorescence of the ovule. The synergid cell is delineated by the dashed line. Scale bar, 20 µm. Also see Figure S3. (G) Immunostaining with anti-CRP810_1.2 antibodies for the female gametophytic mutants myb98/myb98, myb98/MYB98, ccg/CCG, and maa3/MAA3. Representative fluorescence microscopic images of ovules on the septum are shown. Arrows indicate fluorescence around the micropylar end of the ovules. Scale bars, 50 µm. (H) The rate of immunostained ovules to the total number (n) of ovules in the wild type and mutants.