Laboratory of Cellular and Molecular Biology, Center for Cancer Research, NCI, NIH, Bethesda, MD 20892, USA.
Department of Pharmacology, Michigan Medicine, Ann Arbor, MI 48109, USA.
J Cell Sci. 2018 May 4;131(9):jcs216176. doi: 10.1242/jcs.216176.
cells transport adenylyl cyclase A (ACA)-containing vesicles to the back of polarized cells to relay exogenous cAMP signals during chemotaxis. Fluorescence hybridization (FISH) experiments showed that ACA mRNA is also asymmetrically distributed at the back of polarized cells. By using the MS2 bacteriophage system, we now visualize the distribution of ACA mRNA in live chemotaxing cells. We found that the ACA mRNA localization is not dependent on the translation of the protein product and requires multiple cis-acting elements within the ACA-coding sequence. We show that ACA mRNA is associated with actively translating ribosomes and is transported along microtubules towards the back of cells. By monitoring the recovery of ACA-YFP after photobleaching, we observed that local translation of ACA-YFP occurs at the back of cells. These data represent a novel functional role for localized translation in the relay of chemotactic signals during chemotaxis.
细胞将含有腺苷酸环化酶 A（ACA）的囊泡运输到极化细胞的后部，以在趋化过程中传递外源性 cAMP 信号。荧光杂交（FISH）实验表明，ACA mRNA 在后极化细胞中也是不对称分布的。通过使用 MS2 噬菌体系统，我们现在可以在活体趋化细胞中可视化 ACA mRNA 的分布。我们发现 ACA mRNA 的定位不依赖于蛋白质产物的翻译，并且需要 ACA 编码序列内的多个顺式作用元件。我们表明，ACA mRNA 与活跃翻译的核糖体相关联，并沿微管向细胞后部运输。通过监测 ACA-YFP 在光漂白后的恢复情况，我们观察到 ACA-YFP 的局部翻译发生在细胞后部。这些数据代表了在趋化过程中局部翻译在趋化信号传递中的新的功能作用。
