Las β-Galactosidasas y la dinámica de la pared celular

the cell wall is the major determinant of plant cell growth and development. upon a framework of cellulose, in most flowering plants, there are many cross-linking glycans and pectins whose composition and interactions are involved in wall dynamics during growth. the monosaccharide galactose is a key constituent of major non-cellulosic polysaccharides in most plant cell walls: fucogalacto-xyloglucans, (1→3), (1→6)β-d-galactan chains of the type ii arabinogalactan-proteins, (1→4)βd-galactans and related type i arabinogalactans. each of them exhibits a different turnover at specific stages of cell growth and development. for instance, alterations in cell wall assembly or remodeling through hydrolysis of galactosides and galactans in the cell wall, pre-stages certain developmental events, such as the onset of fruit ripening and the initiation of fiber bundles in flax. no endo-galactanases have been found in plants; therefore, exo-galactanases/β-galactosidases are held responsible for the hydrolysis of all cell-wall galactose-containing polymers. the purpose of this paper is to review cell wall galactose-containing polymers and to better understand the biological role of the plant β-galactosidases in the context of the dynamics during cell growth.