Figure 4.

Ethylene reduction affects the growth-inhibitory but not the growth-promoting function of EIN3.

(A) Dry seed size of different ethylene biosynthetic mutants and wild type (WT) after selfing (n = 6508/5322/4751/4736/5390/2911/3453/4966/5597 for WT/mat3/−/sam1sam2/−/sam1sam3/−/sam2sam3/−/acs6-1/−/acs octuple/−/aco2/−/aco2aco3/−). The area of each seed collected from 15 individual plants sown at three different times was measured in ImageJ. A boxplot was generated based on individual seed area calculated in pixels. The blue line shows the WT median.

(B) Dry seeds of WT and acs octuple/− plants. Scale bars, 1 mm.

(C) Dorsoventral endosperm diameter of WT × WT and acs octuple/− × WT seeds in the four-nucleate endosperm stage. Seeds showing abnormal development at the micropylar end (see also Supplemental Figure 4B and 4C) are excluded (n = 53/79 for WT/acs octuple/−).

(D) Frequency of sdn in the seeds in the four- and eight-nucleate endosperm stages (n = 531, 125, 227, 418, 289 for WT × WT, acs1-1/− × acs octuple/−, acs heptuple/− × acs heptuple/−, aco pentuple × aco pentuple, aco quadruple/− × acs heptuple/−). Two-tailed Student’s t-test did not detect significant difference between mutants and WT for sdn frequency.

(E) Schematic model of dual and opposing roles of EIN3 during seed growth. Two-tailed Student’s t-test between WT and mutants: ∗p < 0.05; ∗∗p < 0.01; ∗∗∗∗p < 0.0001. See also Supplemental Figure 4.