RNA localization and local translation are important for numerous cellular functions. In mammals, a class of mRNAs localize to cytoplasmic protrusions in an APC-dependent manner, with roles during cell migration. Here, we investigated this localization mechanism. We found that the KIF1C motor interacts with APC-dependent mRNAs and is required for their localization. Live cell imaging revealed rapid, active transport of single mRNAs over long distances that requires both microtubules and KIF1C. Two-color imaging directly revealed single mRNAs transported by single KIF1C motors, with the 3′UTR being sufficient to trigger KIF1C-dependent RNA transport and localization. Moreover, KIF1C remained associated with peripheral, multimeric RNA clusters and was required for their formation. These results reveal a widespread RNA transport pathway in mammalian cells, in which the KIF1C motor has a dual role in transporting RNAs and clustering them within cytoplasmic protrusions. Interestingly, KIF1C also transports its own mRNA, suggesting a possible feedback loop acting at the level of mRNA transport.

中文翻译：

---

驱动蛋白 KIF1C 将 APC 依赖性 mRNA 转运至细胞突起

RNA 定位和本地翻译对于许多细胞功能很重要。在哺乳动物中，一类 mRNA 以 APC 依赖性方式定位于细胞质突起，在细胞迁移过程中发挥作用。在这里，我们研究了这种本地化机制。我们发现 KIF1C 马达与 APC 依赖性 mRNA 相互作用，并且是它们定位所必需的。活细胞成像显示需要微管和 KIF1C 的长距离快速主动运输单个 mRNA。双色成像直接显示由单个 KIF1C 马达运输的单个 mRNA，3'UTR 足以触发依赖于 KIF1C 的 RNA 运输和定位。此外，KIF1C 仍然与外周多聚体 RNA 簇相关，并且是它们形成所必需的。这些结果揭示了哺乳动物细胞中广泛存在的 RNA 转运途径，其中 KIF1C 马达在转运 RNA 和将它们聚集在细胞质突起中具有双重作用。有趣的是，KIF1C 还转运它自己的 mRNA，这表明在 mRNA 转运水平上可能存在反馈回路。