Hernández-Hernández Valeria, Rueda Denisse, Caballero Lorena, Alvarez-Buylla Elena R, Benítez Mariana
Instituto de Ecología, Universidad Nacional Autónoma de México Mexico City, Mexico ; Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México Mexico City, Mexico ; Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México Mexico City, Mexico.
Posgrado en Ciencias Biomédicas, Universidad Nacional Autónoma de México Mexico City, Mexico ; Departamento de Nanotecnología, Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México Mexico City, Mexico.
Front Plant Sci. 2014 Jun 10;5:265. doi: 10.3389/fpls.2014.00265. eCollection 2014.
Mechanical forces such as tension and compression act throughout growth and development of multicellular organisms. These forces not only affect the size and shape of the cells and tissues but are capable of modifying the expression of genes and the localization of molecular components within the cell, in the plasma membrane, and in the plant cell wall. The magnitude and direction of these physical forces change with cellular and tissue properties such as elasticity. Thus, mechanical forces and the mesoscopic fields that emerge from their local action constitute important sources of positional information. Moreover, physical and biochemical processes interact in non-linear ways during tissue and organ growth in plants and animals. In this review we discuss how such mechanical forces are generated, transmitted, and sensed in these two lineages of multicellular organisms to yield long-range positional information. In order to do so we first outline a potentially common basis for studying patterning and mechanosensing that relies on the structural principle of tensegrity, and discuss how tensegral structures might arise in plants and animals. We then provide some examples of morphogenesis in which mechanical forces appear to act as positional information during development, offering a possible explanation for ubiquitous processes, such as the formation of periodic structures. Such examples, we argue, can be interpreted in terms of tensegral phenomena. Finally, we discuss the hypothesis of mechanically isotropic points as a potentially generic mechanism for the localization and maintenance of stem-cell niches in multicellular organisms. This comparative approach aims to help uncovering generic mechanisms of morphogenesis and thus reach a better understanding of the evolution and development of multicellular phenotypes, focusing on the role of physical forces in these processes.
诸如拉伸和压缩等机械力在多细胞生物体的整个生长发育过程中都发挥着作用。这些力不仅影响细胞和组织的大小与形状，还能够改变基因的表达以及细胞内、质膜中和植物细胞壁中分子成分的定位。这些物理力的大小和方向会随着细胞和组织的特性（如弹性）而变化。因此，机械力及其局部作用产生的介观场构成了重要的位置信息来源。此外，在植物和动物的组织与器官生长过程中，物理过程和生化过程以非线性方式相互作用。在本综述中，我们讨论了在这两类多细胞生物体中，此类机械力是如何产生、传递和感知的，以产生长距离的位置信息。为了做到这一点，我们首先概述了一个潜在的共同基础，用于研究依赖于张拉整体结构原理的模式形成和机械传感，并讨论张拉整体结构可能如何在植物和动物中出现。然后，我们提供了一些形态发生的例子，其中机械力在发育过程中似乎充当位置信息，为诸如周期性结构形成等普遍过程提供了一种可能的解释。我们认为，这些例子可以用张拉整体现象来解释。最后，我们讨论了机械各向同性点的假说，它是多细胞生物体中干细胞龛定位和维持的一种潜在通用机制。这种比较方法旨在帮助揭示形态发生的通用机制，从而更好地理解多细胞表型的进化和发育，重点关注物理力在这些过程中的作用。
