Cell polarity is on PAR with cytokinesis.
Cell polarity is on PAR with cytokinesis.
复制标题
细胞极性与胞质分裂有关。
DOI：
10.1080/15384101.2016.1160667
复制
发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Canman,JulieC
中科院分区：
文献类型：
--
作者：
Davies,Tim;Jordan,ShawnN;Canman,JulieC
胞质分裂是在细胞周期结束时将一个细胞分裂成两个子细胞的过程。1胞质分裂在所有后生动物中被认为是基本相似的，即由有丝分裂纺锤体信号定位和控制的赤道肌球蛋白收缩环驱动的。然而，动物细胞分裂主要有两种类型：对称性和非对称性。对称分裂产生的子细胞具有相同的细胞质和皮质成分，从而产生相同的细胞大小和命运。相反，许多胚胎和干细胞的分裂是不对称的，导致子代细胞的细胞大小和/或细胞命运不同。在对称和/或不对称分裂的细胞中，胞质分裂是否受到差异调控尚不清楚。在细胞不对称分裂过程中，PAR蛋白(分裂缺陷)控制着关键细胞命运决定因素的不平等遗传。2线虫单细胞受精卵是理解前后极性分子调控的重要系统。在这个系统中，受精触发了极性的建立，并在受精卵中形成了相反的前部PAR(APAR)和后部PAR(PPAR)结构域。基于肌动球蛋白的前向皮质血流导致皮质aPAR(肌球蛋白-II、PAR-3、PAR-6、PKC-3和CDC-42)在前细胞皮质上的丰富。同时，皮质PPAR蛋白PAR-2定位于后皮质，在那里它排除了aPAR。APAR和PPAR保持在细胞皮质的相对两侧，这种状态是在细胞质分裂之前和期间通过相互抑制而保持的。2先前认为皮质核心PAR蛋白通过定位有丝分裂纺锤体和纺锤体相关信号间接控制胞质分裂，进而控制胞质分裂过程中的收缩环。然而，对不对称分裂的果蝇神经母细胞的实验表明，当纺锤体受到干扰时，可以形成一个极化相关的收缩环。3.
Cytokinesis is the physical division of one cell into two daughter cells that occurs at the end of the cell cycle. 1 Cytokinesis is thought to be fundamentally similar in all metazoan divisionsthat is, driven by constriction of an equatorial actomyosin contractile ring positioned and controlled by signals from the mitotic spindle. However, there are two main types of animal cell division: symmetric and asymmetric. Symmetric divisions produce daughter cells with equal cytoplasmic and cortical components, and thus the same cell size and fate. In contrast, many embryonic and stem cell divisions are asymmetric, resulting in daughter cells of differing cell size and/or cell fate. It is unknown if cytokinesis is differentially regulated in symmetric and/or asymmetrically dividing cells. During asymmetric cell divisions, the PAR proteins (PARtitioning defective) control the unequal inheritance of key cell fate determinants. 2 The C. elegans single-cell zygote has been a seminal system for understanding the molecular regulation of anterior-posterior (AP) polarity. In this system, fertilization triggers polarity establishment and the formation of opposing anterior PAR (aPAR) and posterior PAR (pPAR) domains within the zygote. Anterior-directed actomyosin-based cortical flow leads to the enrichment of cortical aPARs (myosin-II, PAR-3, PAR-6, PKC-3, and CDC-42) on the anterior cell cortex. At the same time, the cortical pPAR protein PAR-2 localizes to the posterior cortex where it excludes the aPARs. The aPARs and pPARs remain on opposing sides of the cell cortex, a state maintained via mutual inhibition up to and during cytokinesis. 2The core cortical PAR proteins were previously thought to control cytokinesis indirectly by positioning the mitotic spindle and spindle-associated signals, which in turn control the contractile ring during cytokinesis. However, experiments in asymmetrically dividing Drosophila neuroblasts revealed a polaritydependent contractile ring can form when the spindle is perturbed. 3