GoSAMTs are required for pectin methyl-esterification and mucilage release in seed coat epidermal cells

• DOI: 10.3389/fpls.2023.1099573
• Publication Date: 2023-02-08T16:49:04Z
• Authors: Juan Pablo Parra-...; Pablo Sepúlveda-O...; Dayan Sanhueza; Hernán Salinas-Gr...; Henry Temple; Paul Dupree; Susana Saez-Aguayo; Ariel Orellana
• Keywords: Mucilage; Coat; Pectin; Methyl cellulose

Introduction GoSAMTs play a role in the methylation of polysaccharides synthesized by Golgi. Pectin homogalacturonan (HG) methyl-esterification is essential for proper function this polysaccharide cell walls. In order to better understand HG biosynthesis, we analyzed mucilage gosamt mutants. Methods To determine GoSAMT1 and GoSAMT2 utilized epidermal cells seed coats, as these structures produce mucilage, which pectic matrix. We evaluated differences surface morphology quantified release. measured methanol release, used antibodies confocal microscopy analyze mucilage. Results observed morphological on delayed, uneven release gosamt1-1gosamt2-1 double also found changes distal wall length indicating abnormal breakage mutant. Using immunolabeling, confirmed that are involved However, did not find evidence decreasing Confocal analyses detected different patterns adherent greater number low-methyl-esterified domains near coat surface, correlates with “egg-box” region. shift partitioning between Rhamnogalacturonan-I soluble layers mutant, correlated increased amounts arabinose arabinogalactan-protein Discussion The results show mutant plants less methyl esterified, resulting more egg-box structures, stiffen walls change rheological properties surface. suggests compensation mechanisms were triggered