Mechanisms of Spindle Positioning Biology Diagrams The direction in which a cell divides is determined by the orientation of its mitotic spindle at metaphase. Spindle orientation is therefore important for a wide range of developmental processes, ranging from germline stem cell division to epithelial tissue homeostasis and regeneration. In multiple cell types in multiple animals, spindle orientation is controlled by a conserved biological
The cell division axis is determined by the position of the mitotic spindle. How geometrical cues influence spindle orientation is analysed in cells cultured on micropatterns. These experiments Summary Proper spatial control of the cell division plane is essential to any developing organism. In most cell types, the relative size of the two daughter cells is determined by the position of the mitotic spindle within the geometry of the mother cell. We review the underlying mechanisms responsible for positioning of the mitotic spindle, both in cases where the spindle is placed in the Abstract Accurate positioning of spindles is essential for asymmetric mitotic and meiotic cell divisions that are crucial for animal development and oocyte maturation, respectively. The predominant model for spindle positioning, termed "cortical pulling," involves attachment of the microtubule-based motor cytoplasmic dynein to the cortex, where it exerts a pulling force on microtubules that
Force and the spindle: Mechanical cues in mitotic spindle orientation Biology Diagrams
Abstract The mechanical environment of a cell has a profound effect on its behaviour, from dictating cell shape to driving the transcription of specific genes. Recent studies have demonstrated that mechanical forces play a key role in orienting the mitotic spindle, and therefore cell division, in both single cells and tissues. Zellag et al. use in situ live-cell imaging to show that mitotic spindles orient parallel to the tissue plane in the C. elegans germ line. They propose a mechanism wherein basal centrosome positioning in interphase and a cycle of LIN-5/NuMA cortical localization establishes and maintains proper germ cell spindle orientation during mitosis.
The orientation of cell divisions regulates tissue architecture and cell fate and depends on mitotic spindle positioning, which is controlled by intracellular and extracellular cues. Building on
The spatiotemporal distribution of LIN Biology Diagrams
Proper spatial control of the cell division plane is essential to any developing organism. In most cell types, the relative size of the two daughter cells is determined by the position of the mitotic spindle within the geometry of the mother cell. We review the underlying mechanisms responsible for positioning of the mitotic spindle, both in cases where the spindle is placed in the center of Abstract Accurate positioning of spindles is essential for asymmetric mitotic and meiotic cell divisions that are crucial for animal development and oocyte maturation, respectively. The predominant model for spindle positioning, termed "cortical pulling," involves attachment of the microtubule-based motor cytoplasmic dynein to the cortex, where it exerts a pulling force on microtubules
