Endosomal transport of septin mRNA and protein indicates local translation on endosomes and is required for correct septin filamentation
Endosomal transport of septin mRNA and protein indicates local translation on endosomes and is required for correct septin filamentation
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DOI：
10.1002/embr.201338037
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发表时间：
2014-01-01
期刊：
影响因子：
7.7
通讯作者：
Feldbruegge, Michael
中科院分区：
文献类型：
--
作者：
Baumann, Sebastian;Koenig, Julian;Feldbruegge, Michael
内小体通过沿微管穿梭，远距离运输脂肪和蛋白质。它们的表面也携带着mRNA，但这一贩运过程的确切分子功能尚不清楚。通过对极化真菌菌丝的活细胞成像，我们显示了在相同的穿梭内体上，Septin mRNA和编码的Septin蛋白依赖于微管的运输。与Septin mRNA在内体上翻译的假设一致，Septin蛋白在内体上的积累需要Septin mRNA的募集。此外，核糖体蛋白与穿梭内糖体共定位，但前提是存在信使核糖核酸。重要的是，内体运输对于有效地将间隔蛋白输送到生长极的细丝是必不可少的，这是建立单极生长所必需的过程。因此，我们认为局部的信使核糖核酸翻译将内吞体内装载到间隔素内，以便组装和有效地运送到间隔素丝。
Endosomes transport lipids and proteins over long distances by shuttling along microtubules. They also carry mRNAs on their surface, but the precise molecular function of this trafficking process is unknown. By live cell imaging of polarized fungal hyphae, we show microtubule-dependent transport of septin mRNA and encoded septin protein on the same shuttling endosomes. Consistent with the hypothesis that septin mRNA is translated on endosomes, the accumulation of septin protein on endosomes requires the recruitment of septin mRNA. Furthermore, ribosomal proteins co-localise with shuttling endosomes, but only if mRNA is present. Importantly, endosomal trafficking is essential for an efficient delivery of septin protein to filaments at growth poles, a process necessary to establish unipolar growth. Thus, we propose that local mRNA translation loads endosomes with septins for assembly and efficient delivery to septin filaments.