Bullock T L, McCoy A J, Kent H M, Roberts T M, Stewart M
MRC Laboratory of Molecular Biology, Cambridge, UK.
Nat Struct Biol. 1998 Mar;5(3):184-9. doi: 10.1038/nsb0398-184.
Cell locomotion in amoeboid nematode sperm is generated by the vectorial assembly and bundling of filaments of the major sperm protein (MSP). MSP filaments are constructed from two helical subfilaments and here we describe the structure of putative MSP subfilament helices determined by X-ray crystallography at 3.3 A resolution. In addition to establishing the interfaces involved in polymerization, this structural model shows that the MSP helices are constructed from dimers and have no overall polarity, suggesting that it is unlikely that molecular motors play a direct role in the generation of protrusive force in these amoeboid cells.
变形虫样线虫精子中的细胞运动是由主要精子蛋白（MSP）细丝的矢量组装和捆绑产生的。MSP细丝由两条螺旋亚细丝构成，在此我们描述了通过X射线晶体学以3.3埃分辨率确定的假定MSP亚细丝螺旋的结构。除了确定参与聚合的界面外，该结构模型还表明MSP螺旋由二聚体构成且没有整体极性，这表明分子马达不太可能在这些变形虫样细胞中产生突出力的过程中直接发挥作用。
