“…The release of mucilage upon hydration depends on correct branching of RG I and on HG methylesterification (Dean et al, 2007;Macquet et al, 2007;Rautengarten et al, 2008;Arsovski et al, 2009;Saez-Aguayo et al, 2013;Voiniciuc et al, 2013). An adherent capsule, representing 35% of the total mucilage produced (Voiniciuc et al, 2015b), is anchored around each seed and is associated with ray-like structures synthesized in part by CELLULOSE SYNTHASE (CESA) proteins (Harpaz-Saad et al, 2011;Mendu et al, 2011;Sullivan et al, 2011;Griffiths et al, 2015) and potentially assembled by COBRA-LIKE2 (Ben-Tov et al, 2015). Two additional proteins, SALT-OVERLY SENSITIVE5 (SOS5; also annotated as FASCICLIN-LIKE ARABINOGALACTAN PROTEIN4 [FLA4]) and the receptor-like kinase FEI2 (named after the Chinese word for fat) are required for mucilage adherence, but their functions remain unclear (Harpaz-Saad et al, 2011;Griffiths et al, 2014).…”