Mechanically, the Shoot Apical Meristem of Arabidopsis Behaves like a Shell Inflated by a Pressure of About 1 MPa.

摘要: In plants, the shoot apical meristem contains stem cells and is responsible for generation of all aerial organs. Mechanistically, organogenesis associated with an auxin-dependent local softening epidermis. This has been proposed to be sufficient trigger outgrowth, because epidermis thought under tension stiffer than internal tissues in part plant. However, this not directly demonstrated meristem. Here we tested hypothesis Arabidopsis using indentation methods modeling. We considered two possible scenarios: either does have unique properties behaves as a homogeneous linearly-elastic tissue, or exhibits response shell pressure. Large depths measurements large tip (~size meristem) were consistent shell-like behavior. also allowed us deduce value turgor pressure, estimated at 0.82±0.16 MPa. Indentation atomic force microscopy provided pressure epidermis, further confirming range values obtained from deformations. Altogether, our data demonstrate that like MPa support key role shaping apex.