Figure 1.

Characterization of AGP31. A, Structure of AGP31. Shaded regions are four exact repeat units. Underlined regions are two longer repeat units. The smallest repeat unit is PPXX. The italicized region is the predicted signal peptide; the bold region is the His-rich region. Boxed regions are the predicted APAPAP module for arabinogalactan attachment and N-glycosylation sites. B, Neighbor-joining tree generated from the alignment of full-length amino acid sequences of the homologs of AGP31. Numbers indicate the percentage of 1,000 bootstrap replicates. C, Western blot showing that AGP31 exists in AGP precipitation of cell wall protein. Lane 1, AGP fraction from wild-type plants; lane 2, AGP fraction from transgenic plants expressing 35S∷AGP31∷myc. D, Purified AGP31. AGP31 was isolated from high-salt eluted cell wall protein by a Ni-NTA column and deglycosylated by TFMS. Approximately 2 μg of native and deglycosylated AGP31 were separated by SDS-PAGE on a 15% gel and stained by Coomassie Blue. Lane 1, Native AGP31; lane 2, deglycosylated AGP31.