Fig. 1.

AKIN10 is expressed during embryogenesis and phosphorylates FUS3. (A) Expression pattern of AKIN10 during seed development in Arabidopsis grown under long days (21 °C/18 °C). Confocal images showing AKIN10–GFP expression predominantly in the cytoplasm and occasionally in the nuclei of the embryo proper in the triangular (top, left), heart (top, right), torpedo (center and bottom, left), and bent cotyledon (center and bottom, right) stage embryos. Bottom images are magnifications of torpedo (left) and bent cotyledon (right) embryos shown in the center panels. Scale bars from left: top, 20 µm; middle, 50 µm, 200 µm; bottom, 20 µm. (B) AKIN10 protein was detected throughout seed development from total soluble protein of isolated seeds using anti-AKIN10. Ponceau stain is shown as the loading control. (C) In-gel kinase assay using purified GST–FUS3 (top) or GST (bottom) as the substrates and cell extracts from siliques showing a phosphorylation band at the expected size of AKIN10 at the heart/torpedo stages. Purified GST was used as the negative control. (This figure is available in colour at JXB online.)