Loss of UBIQUITIN-PROTEIN LIGASE 3 (UPL3) impairs cellulose-xylan structural organization in Arabidopsis seed mucilage.

Loss of UPL3 disrupts cellulose and xylan organization, enlarging seed mucilage halos and impairing structural interactions in Arabidopsis seed coat.

• Why it matters: Understanding the regulation of polysaccharide interactions in seed mucilage is crucial for insights into seed dispersal and germination, yet key proteins involved remain unidentified.
• What they did: Using reverse genetics, researchers examined UPL3, a nucleus-localized E3 ligase, revealing its role in organizing cellulose and xylan networks without affecting their biosynthesis, and analyzing its genetic interactions with other mucilage-related genes.
• The result: Disruption of UPL3 causes abnormal cellulose structures and altered xylan distribution, highlighting its essential regulatory function in maintaining proper mucilage architecture and polysaccharide interplay.