Lim Chinten James, Zawadzki Karl A, Khosla Meenal, Secko David M, Spiegelman George B, Weeks Gerald
Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada V6T1Z3.
Exp Cell Res. 2005 May 15;306(1):47-55. doi: 10.1016/j.yexcr.2005.02.002.
In addition to its previously established roles in cAMP relay and cAMP chemotaxis, loss of signal transduction through the RasC protein was found to impact a number of vegetative cell functions. Vegetative rasC- cells exhibited reduced random motility, were less polarized and had altered F-actin distribution. Cells lacking RasC also contained more protein and were larger in size than wild type cells. These increases were associated with increased liquid phase endocytosis. Despite the increase in cell size, cytokinesis was relatively normal and there was no change in the rate of cell division. rasC- cells also chemotaxed poorly to folate and exhibited reduced F-actin accumulation, reduced ERK2 phosphorylation and reduced Akt/PKB phosphorylation in response to folate, indicating that RasC was also involved in transducing chemotactic signals in vegetative cells.
除了其先前确定的在环磷酸腺苷（cAMP）传递和cAMP趋化作用中的作用外，还发现通过RasC蛋白的信号转导缺失会影响许多营养细胞功能。营养型rasC-细胞表现出随机运动性降低、极化程度降低且F-肌动蛋白分布改变。缺乏RasC的细胞也比野生型细胞含有更多蛋白质且体积更大。这些增加与液相内吞作用增加有关。尽管细胞体积增大，但胞质分裂相对正常，细胞分裂速率没有变化。rasC-细胞对叶酸的趋化性也很差，并且在响应叶酸时表现出F-肌动蛋白积累减少、ERK2磷酸化减少和Akt/PKB磷酸化减少，表明RasC也参与了营养细胞中趋化信号的转导。
