Download Mechanical constraints of primary cell wall expansion

Mechanical constraints of primary cell wall expansion
Ingo Burgert
Max-Planck-Institute of Colloids and Interfaces, Department of Biomaterials
Plant growth and development decisively depend on the ability of cells to enlarge during their
differentiation, however, the underlying mechanisms of primary cell wall expansion still
remain partly elusive. The primary cell wall consisting of cellulose fibrils, hemicelluloses,
pectin, and protein has to be both strong enough to withstand high stresses due to
hydrostatic pressure and external loads as well as flexible enough to allow a tremendous
expansion of the cell. To shed light on this mechanical paradox an interdisciplinary
combination of biomechanical, biochemical, and physiological approaches is required. In this
talk the mechanical constraints of cell wall expansion are discussed from a plant
biomechanics perspective highlighting the crucial role of cellulose microfibril orientation and
fibre and matrix interaction in the course of cell enlargement. Micromechanical tests to
determine mechanical properties of primary cell walls of native and genetically modified
Arabidopsis hypocotyls are presented.