Fig. 6.

Partial complementation of arp6 klu MMC specification defects by WRKY28 overexpression. (A) Siliques of plants with the indicated genotypes. (Scale bar: 1 mm.) (B) Quantification of seed set in arp6 klu plants with and without the WRKY28 transgene. Values are means ± SD (n = 6; **P < 0.01). (C) Quantification of aberrant MMC specification in premeiotic ovules (**P < 0.01 by Pearson’s χ² test). (D) DIC images of premeiotic ovules with the indicated genotypes. Numbers denote the frequencies of the phenotypes shown. Red arrows indicate multiple enlarged cells. (Scale bar: 10 µm.) (E) Signal corresponding to pKNU:WRKY28-GFP expression in a premeiotic ovule (WT background). (F) Proposed model for the coordinated action of KLU and SWR1 in suppressing ectopic MMC fate by promoting WRKY28 expression in the hypodermal somatic cells surrounding the MMC. II, inner integument; OI, outer integument.