Silverman M A, Peck R, Glover G, He C, Carlin C, Banker G
Center for Research on Occupational and Environmental Toxicology, L606, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.
Mol Cell Neurosci. 2005 Jun;29(2):173-80. doi: 10.1016/j.mcn.2005.02.008.
One model for dendritic protein sorting in neurons is based on parallels with basolateral targeting in Madin-Darby Canine Kidney (MDCK) epithelial cells. The goal of this study was to further evaluate this model by analyzing the neuronal targeting of several proteins that contain well-defined basolateral sorting motifs. When we expressed FcRgammaII-B2 and CD44, two basolateral markers whose sorting depends on dihydrophobic motifs, they were unpolarized in hippocampal neurons. We also assessed the localization of the Epidermal Growth Factor Receptor (EGFR), a basolateral protein whose sorting signal contains a proline-rich motif and two dihydrophobic motifs. EGFR was restricted to the dendrites in neurons and relied on the same sorting signal for proper targeting. These results show that the dendritic sorting machinery in neurons does not recognize dihydrophobic-based basolateral sorting signals. In contrast, the sorting signal present in EGFR directs both basolateral and dendritic targeting and defines a novel dendritic targeting motif.
一种关于神经元中树突状蛋白分选的模型是基于与犬肾（MDCK）上皮细胞基底外侧靶向的相似性。本研究的目的是通过分析几种含有明确基底外侧分选基序的蛋白质的神经元靶向，进一步评估该模型。当我们表达FcRγII - B2和CD44这两种其分选依赖于双疏水基序的基底外侧标记物时，它们在海马神经元中没有极性。我们还评估了表皮生长因子受体（EGFR）的定位，EGFR是一种基底外侧蛋白，其分选信号包含一个富含脯氨酸的基序和两个双疏水基序。EGFR在神经元中局限于树突，并且依赖相同的分选信号进行正确靶向。这些结果表明，神经元中的树突状分选机制不识别基于双疏水的基底外侧分选信号。相反，EGFR中存在的分选信号指导基底外侧和树突状靶向，并定义了一种新的树突状靶向基序。
