Supplemental Fig. 1

Immunogold detection of mannans in vascular bundle cells of the apical stem labeled by LM22. a, b

Labeling was initially detected in metaxylem vessels (V) during S2 formation and no labeling was detected

in xylary fibers (F) at the S1 formation stage. Note specific labeling in cytoplasm. c, d Protoxylem vessels

(pV) showed much stronger labeling than V with strong labeling in outer cell wall regions. Labeling in pV

was much lower than LM21 (Fig. 2e, f). Ca, cambium. Bars = 500 nm

Supplemental Fig. 2

Immunogold detection of mannans in parenchymatous cells of the basal stem labeled by LM21. No specific

labeling was detected in the cell wall of any parenchymatous cells. Bars = 500 nm

Supplemental Fig. 3 

 

Supplemental Fig. 3 continued

Immunogold detection of pectic homoglacturonan (HG) in basal stem labeled by LM19. Strong labeling

was detected in the cell wall of all parenchymatous cells (a–f). Labeling in vascular cells was limited in the

middle lamella regions (g, h). F, xylary fiber; V, metaxylem vessels. Bars = 500 nm

Supplemental Fig. 4

Immunogold detection of pectic homoglacturonan (HG) in the basal stem after pectinase treatment labeled

by LM19. Labeling was significantly reduced in all cell types after pectinase treatment (Supple. Fig. 2). F,

xylary fiber; V, metaxylem vessels. Bars = 500 nm