* MSSセミナー@京都 #12 [#g7e32a97] ** 日時 [#mc5175bb] - 2009年07月15日(水)15:00〜 ** 場所 [#t2ef4242] - 京都大学桂キャンパス Aクラスター A2-302 - [[アクセスマップ:http://www.kyoto-u.ac.jp/ja/access/campus/map6r_k.htm]] ** 講師: Prof. P. Ziherl(University of Ljubljana) [#m233e920] *** 題目: [#wb8194f4] Mechanical models of simple cell aggregates *** ''概要'' [#ea3ed8fc] Many aspects of the shape of animal cell aggregates and tissues can be interpreted in terms of a theoretical model that includes membrane bending elasticity and intermembrane attraction. Using a combination of numerical and variational results, we show that this approach reproduces the morphology of linear aggregates of erythrocytes as well as the structure of epithelia and endothelia of several animals as examples of sheet-like and bulk cell aggregates, respectively. The insight provided suggests that the anisotropic, reduced-dimensionality aggregates are stabilized by the competition of membrane elasticity and adhesion. We discuss the implications of these results for two key stages of embryogenesis: i) formation of the blastula as a curved two-dimensional cell aggregate and ii) gastrulation whereby the invaginated part of the blastula exhibits directional growth. The theoretical framework based on membrane elasticity and adhesion can also be used to study the shape of the Golgi apparatus. We focus on the role of the non-trivial topology of the cisternae laden with openings called fenestrations, which may be responsible for the large effective bending rigidity of the cisternae.