Long-Distance Movement of Aspergillus nidulans Early Endosomes on Microtubule Tracks
Long-Distance Movement of Aspergillus nidulans Early Endosomes on Microtubule Tracks
复制标题
DOI：
10.1111/j.1600-0854.2008.00848.x
复制
发表时间：
2009-01-01
期刊：
影响因子：
4.5
通讯作者：
Penalva, Miguel A.
中科院分区：
文献类型：
--
作者：
Abenza, Juan F.;Pantazopoulou, Areti;Penalva, Miguel A.
在真菌菌丝细胞中，细胞内膜运输受到相对长的细胞内距离和生长模式的限制，仅受顶端延伸的限制。内吞作用在菌丝顶端生长中起着关键作用，它涉及到分泌膜向顶端区域的传递与顶端下的补偿性内吞作用的耦合。然而，丝状真菌内体区室的身份，动力学和功能仍然在很大程度上未被探索。构巢曲霉RabA（Rab 5）定位于在微管（MT）轨道上显示长距离双向运动的内体群体，并且在染料内化后不久用FM 4 -64标记。RabA（Rab 5）膜不与大部分静止的成熟内体/空泡重叠。动力蛋白向MT+末端的传递受损或使用动力蛋白重链nudA 1（ts）突变下调细胞质动力蛋白导致RabA（Rab 5）内体膜在尖端异常的NudA 1隔室中积累，强烈支持A.动力蛋白装载区的巢菌菌丝顶端。我们发现，SynA小突触泡蛋白内吞回收货物交通通过这个区域，这强烈支持的论点，极化菌丝生长涉及协会的内吞回收与位于尖端的MT的正端，内吞内化领附近。
In fungal hyphal cells, intracellular membrane trafficking is constrained by the relatively long intracellular distances and the mode of growth, exclusively by apical extension. Endocytosis plays a key role in hyphal tip growth, which involves the coupling of secretory membrane delivery to the apical region with subapical compensatory endocytosis. However, the identity, dynamics and function of filamentous fungal endosomal compartments remain largely unexplored. Aspergillus nidulans RabA(Rab5) localizes to a population of endosomes that show long range bidirectional movement on microtubule (MT) tracks and are labelled with FM4-64 shortly after dye internalization. RabA(Rab5) membranes do not overlap with largely static mature endosomes/vacuoles. Impaired delivery of dynein to the MT plus ends or downregulation of cytoplasmic dynein using the dynein heavy chain nudA1(ts) mutation results in accumulation of RabA(Rab5) endosomal membranes in an abnormal NudA1 compartment at the tip, strongly supporting the existence in A. nidulans hyphal tips of a dynein loading region. We show that the SynA synaptobrevin endocytic recycling cargo traffics through this region, which strongly supports the contention that polarized hyphal growth involves the association of endocytic recycling with the plus ends of MTs located at the tip, near the endocytic internalization collar.