SAO-1在第一次细胞分裂中调节细胞骨架的基础研究

BASIC RESEARCH ON SAO-1 REGULATING CYTOSKELETON IN THE FIRST CELL DIVISION

王梦君

11849118

硕士

生物工程

谢宇聪

2020-06-05

2020-07-12

哈尔滨工业大学

深圳

SAO-1蛋白含有高度保守的GYF结构域，GYF结构域蛋白大多数存在于真核生物中，前人的研究只发现了少数几个包含GYF结构域的蛋白质，且对SAO-1蛋白确切作用还知之甚少。本论文通过构建SAO-1突变体线虫株，在秀丽隐杆线虫的胚胎时期，探讨了SAO-1在第一次细胞分裂过程中对细胞骨架的调控作用。本论文发现，在秀丽隐杆线虫胚胎第一次细胞分裂过程中，SAO-1缺失会导致假分裂沟变浅、分裂沟闭合点居中、中心体旋转减弱等一系列表型，影响了第一次细胞质的分裂，还影响了胚胎的存活率。同时，实验结果还表明，SAO-1缺失会导致细胞皮层蛋白NMY-2、ANI-1之间的连接减弱甚至消失，破坏其网状结构。卵裂沟的形成和内侵与中心纺锤体有关，这些实验结果在一定程度上表明，SAO-1缺失破坏了细胞皮层NMY-2、ANI-1的网状结构，使皮层的收缩动力减弱，中心体旋转减弱，最终导致假分裂沟变浅和分裂沟的闭合位点异常的表型。本论文同时还发现在第一次细胞分裂过程中，DLC-1敲低的表型与SAO-1缺失表型一致。DLC-1的缺失同样可以破坏NMY-2、ANI-1、Actin之间的网状结构，导致细胞皮层的收缩力减弱，中心体旋转减弱，中间纺锤体定位异常，卵裂沟的入侵受到影响，最终出现假分裂沟变浅和分裂沟闭合点异常的相似表型。此外，我们发现SAO-1缺失可以显著降低DLC-1在胚胎细胞质中的表达，并通过qPCR实验证明了DLC-1表达量的急剧降低并不是由于SAO-1对DLC-1转录水平影响造成的，可能是由于SAO-1影响了DLC-1的代谢或稳定性造成的。通过一系列研究发现内质网结构破坏后，SAO-1在细胞质分布不均；SAO-1或DLC-1缺失后，内质网蛋白会在胞质和细胞皮层聚集成块。综上所述，本论文研究结果表明SAO-1参与了细胞分裂过程，并对细胞骨架调节起到一定作用，为深入研究GYF结构域蛋白功能提供新视角。

The SAO-1 protein contains a highly conserved GYF domain. Most of the GYF domain proteins are found in eukaryotes. Previous studies have found that only a few which contain the GYF domain, however, the function of GYF domain contained proteins is still unknown. In this thesis, by constructing the SAO-1 mutant C. elegans, in the embryo stage of C elegans, we explored the regulatory effect of SAO-1 on the cytoskeleton during the first cell division.We found that during the first cell division of the embryo, the depletion of SAO-1 will cause a series of phenotypes, that is the pseudo cleavage furrow to become shallow, the furrow close point near the central point and the centrosome rotation weakening, affecting the first cytoplasmic division. And it affects the developmental survival rate of the embryo. At the same time, the experimental results also show that the depletion of SAO-1 will lead to weakened or no connection between the cell cortex proteins NMY-2 and ANI-1, and break the network structure. The formation and ingression of cleavage furrow are related to the central spindle. These experimental results show to a certain extent that the depletion of SAO-1 breaks the network structure of NMY-2 and ANI-1, and weakens the contractile of the cortex. And then the centrosome rotation weakens, which eventually leads to the shallowness of pseudo cleavage and abnormal furrow close point.Second, we found that during the first cell division, the DLC-1 knockdown phenotype was consistent with the SAO-1 deletion phenotype. Similarly, the knockdown of DLC-1 can break the network structure between NMY-2, ANI-1, and Actin. The contractile force of the cell cortex is weakened, and the centrosome rotation is weakened. A similar phenotype in which the pseudo cleavage becomes shallower and the cleavage closing point is abnormal eventually appears. At the same time, it was found that the depletion of SAO-1 can significantly reduce the expression of DLC-1 in the cytoplasm of embryo, and it was proved by qPCR experiments that the dramatic decrease of DLC-1 expression was not caused by the DLC-1 transcription level. It may be that the degradation or stability of DLC-1 was influenced by SAO-1.

胞质分裂 细胞骨架 SAO-1 GYF结构域 动力蛋

cytokinesis cytoskeleton SAO-1 GYF domain dynein

中文

联合培养

南方科技大学

王梦君. SAO-1在第一次细胞分裂中调节细胞骨架的基础研究[D]. 深圳. 哈尔滨工业大学,2020.