Department of Biological Sciences, Center for Cellular Neurobiology and Neurodegeneration Research, University of Massachusetts-Lowell, Lowell, Massachusetts 01854, USA.
Cytoskeleton (Hoboken). 2011 Nov;68(11):589-95. doi: 10.1002/cm.20535. Epub 2011 Oct 20.
Neurofilaments (NFs) are among the most abundant constituents of the axonal cytoskeleton. NFs consist of four subunits, termed NF-H, NF-M and NF-L, corresponding to heavy, medium and light in reference to their molecular mass and α-internexin. Phosphorylation of the C-terminal "sidearms" of NF-H and NF-M regulates the ability of NFs to form a cytoskeletal lattice that supports the mature axon. C-terminal phosphorylation events have classically been considered to regulate NF axonal transport. By contrast, studies demonstrating that NF axonal transport was not accelerated following sidearm deletion provided evidence that phosphorylation does not regulate NF transport. Herein, we demonstrate how comparison of transport and distribution of differentially phosphorylated NFs along axons identify common ground between these hypotheses and may resolve this controversy.
神经丝（NFs）是轴突细胞骨架中最丰富的成分之一。NFs 由四个亚基组成，分别称为 NF-H、NF-M 和 NF-L，它们分别对应于分子量较大的重链、中等分子量的中链和分子量较小的轻链，以及α-中间丝。NF-H 和 NF-M 的 C 末端“侧臂”的磷酸化调节 NF 形成支持成熟轴突的细胞骨架晶格的能力。C 末端磷酸化事件通常被认为调节 NF 轴突运输。相比之下，研究表明侧臂缺失后 NF 轴突运输并没有加速，这提供了证据表明磷酸化不会调节 NF 运输。本文中，我们展示了如何比较沿轴突的不同磷酸化 NF 的运输和分布，以确定这些假说之间的共同点，并可能解决这一争议。
