Department of Life Science, College of Natural Science, Daejin University, Kyeonggido, Korea.
Exp Mol Med. 2011 Mar 31;43(3):153-60. doi: 10.3858/emm.2011.43.3.019.
Phosphatidylinositol phosphates (PtdInsPs) are ubiquitous membrane phospholipids that play diverse roles in cell growth and differentiation. To clarify the regulation mechanism acting on neurofilament light chain (NF-L) self assembly, we examined the effects of various PtdInsPs on this process. We found that PtdInsPs, including PI(4,5)P((2)), directly bind to the positively charged Arg(54) of murine NF-L, and this binding promotes NF-L self assembly in vitro. Mutant NF-L (R53A/R54A) proteins lacking binding affinity to PtdInsPs did not have the same effect, but the mutant NF-L proteins showed greater self assembly than the wild-type in the absence of any PtdInsP. These results collectively suggest that Arg(54) plays a pivotal role in NF-L self assembly by binding with PtdInsPs.
磷脂酰肌醇磷酸酯（PtdInsPs）是普遍存在的膜磷脂，在细胞生长和分化中发挥多种作用。为了阐明作用于神经丝轻链（NF-L）自组装的调节机制，我们研究了各种 PtdInsPs 对这一过程的影响。我们发现，PtdInsPs，包括 PI(4,5)P((2))，直接结合到鼠 NF-L 的带正电荷的 Arg(54)上，这种结合促进 NF-L 在体外的自组装。缺乏与 PtdInsPs 结合亲和力的突变 NF-L（R53A/R54A）蛋白没有相同的作用，但在没有任何 PtdInsP 的情况下，突变 NF-L 蛋白的自组装比野生型更强。这些结果共同表明，Arg(54)通过与 PtdInsPs 结合在 NF-L 自组装中发挥关键作用。
