Newell P C, Liu G
Department of Biochemistry, University of Oxford, UK.
Bioessays. 1992 Jul;14(7):473-9. doi: 10.1002/bies.950140708.
Streamer F mutants have been found to be useful tools for studying the pathway of signal transduction leading to chemotactic cell movement. The primary defect in these mutants is in the structural gene for the cyclic GMP specific phosphodiesterase. This defect allows a larger and prolonged peak of cyclic GMP to be formed in response to the chemotactic stimulus, cyclic AMP. This characteristic aberrant pattern of cyclic GMP accumulation in the streamer F mutants has been correlated with similar patterns of changes in the influx of calcium from the medium, myosin II association with the cytoskeleton, myosin phosphorylation and a decrease in speed of movement of the amoebae. From these studies a sequence of events can be deduced that leads from cell surface cyclic AMP stimulation to cell polarization prior to movement of the amoebae in response to the chemotactic stimulus.
已发现趋化因子F突变体是研究导致趋化性细胞运动的信号转导途径的有用工具。这些突变体的主要缺陷在于环鸟苷酸特异性磷酸二酯酶的结构基因。这种缺陷使得在趋化刺激物环磷酸腺苷（cyclic AMP）的作用下，能够形成更大且持续时间更长的环鸟苷酸峰值。趋化因子F突变体中环鸟苷酸积累的这种特征性异常模式，与来自培养基的钙流入、肌球蛋白II与细胞骨架的结合、肌球蛋白磷酸化以及变形虫运动速度降低的类似变化模式相关。从这些研究中可以推断出一系列事件，这些事件从细胞表面环磷酸腺苷刺激开始，在变形虫响应趋化刺激物而移动之前导致细胞极化。
