Subcellular localization of FAX2 and FAX4 and their transcript levels in different tissues of Arabidopsis. A, GFP signals and chlorophyll fluorescence signal from the protoplast of the Pro-35s::FAX2 and Pro-35s::FAX4 gDNA-GFP transgenic Arabidopsis. PIC1-GFP was used as a chloroplast inner envelope marker. B, Relative expression of FAX2 and FAX4 transcripts in tissues of Arabidopsis roots (R), stems (S), leaves (L), flowers (F), siliques from 4–6 DAF (S1), siliques from 10–12 DAF (S2), and siliques from 16–18 DAF (S3). Student’s t test (mean ± sd of n = 3–4 tissue samples). C, RNA in situ hybridization of FAX2 and FAX4 in siliques at different seed development stages. The siliques of Col-0 were cross-sectioned for hybridization with antisense and sense probes of FAX2 and FAX4.