Fig. 5: SYAC1 regulates composition of cell wall and alters its physical properties.

a SYAC1 affects α-Amylase secretion index determined by quantifying ratio of the α-Amylase activity in the medium and in the cells. Transient co-expression of SYAC1 with α-Amylase (Amy) and its derivatives carrying different C-terminal sorting motifs, including vacuolar sorting (Amy-spo) and ER retention (Amy-HDEL) motif. (n = 4 biological and 2 technical replicates; average ± SE). Expression of SYAC1 fusion constructs confirmed by western blot analysis (insets) using anti-HA specific antibodies. b Ruthenium red–stained seed coat mucilage after imbibition of wild-type, SYAC1-GFPox, syac1-3, and syac1-5 seeds. Representative images shown (~100 seeds stained per line). Scale bar 200 μm. c FT-IR measurements in 4-day-old etiolated hypocotyls show alterations in cell wall composition in SYAC1-HAox lines. d The amount of galacturonic acid extracted from 4-day-old etiolated hypocotyls (n = 4–6, average ± SE). Wild type I represents respective control to SYAC-GFPox and GFP-SYAC1ox. Wild type II was isolated from syac1-5 heterozygote population. e The apparent Young modules measured by atomic force microscopy (AFM) in 4-day-old etiolated hypocotyls of wild type and SYAC1-GFPox. In the boxplots, center lines show the medians; box limits indicate the 25th and 75th percentiles as determined by Origin software; whiskers extend 1.5 times the interquartile range from the 25th and 75th percentiles, individual data points are represented by dots, n = 10–14. Significant differences are indicated as *P < 0.05, **P < 0.01, and ***P < 0.001 (t-test).