Figure 1.
The glycosyl sequence of RG-II.
RG-II is composed of an α-1,4-linked homogalacturonan backbone that is substituted with four side chains A to D. The underlined sugars are absent in Arabidopsis. Only the apiosyl residue of side chain A is involved in the borate-diester cross-linking of RG-II.
Figure 2.
Flow chart of the 7-step filtering strategy used to select putative RG-II specific GTs.
At : Arabidopsis thaliana, Os : Oryza sativa.
Table 1.
List of genes encoding putative glycosyltransferases involved in RG-II biosynthesis that were selected in Arabidopsis thaliana and Oryza sativa genomes through the bioinformatics filtering process.
Figure 3.
Coexpression and intersection coexpression networks.
Gene coexpression networks for (A) Arabidopsis and (B) Oryza sativa GT candidate genes generated using an edge weighted force directed approach, based on data retrieved from ATTED-II and visualised in Cytoscape 2.8 (http://www.cytoscape.org). C) Intersection coexpression generated from the two networks in order to highlight conserved coexpression relationships between networks of the two species. • (purple): Guide genes (AtRGXT4, AtKDSA1-2, AtKDSB, OsRGXT, OsKDSA2, OsAXS), ⧫ (pink): GT4, ▪ (green): GT8, ▴ (blue): GT29, ▪ (orange): GT31, ▴(green): GT32, ⧫ (grey): GT68, • (brown): GT92, ▴ (blue): non-CAZy GT-A like, ▴ (red): non-CAZy GT-B like, ○ (yellow): GT77, ▪ (blue): GT1-like.
Figure 4.
Phylogenetic tree of Arabidopsis sequences harboring a PF10250 (DUF246) domain.
Figure 5.
Multiple sequence alignement of GT-B like candidates (PF10250, DUF246).
Multiple sequence alignments of GT-B like candidates with C. elegans POFUT1 and three GT68 fucosyltransferases, including the human POFUT2, showing the three conserved peptide regions (denoted I, II, and II). Amino acids indicated in red and underlined correspond to the catalytic HxR sequence in motif I, and D residue (motif II) and STF (motif III) that are involved in the binding of GDP [63],[71]. The accession numbers (from UniprotKB/Swiss-Prot) for the non plant sequences are: Q18014 (CePOFUT1), Q9W589 (DmPOFUT2) and Q9Y2G5 (hPOFUT2).