X-ray diffraction from flight muscle with a headless myosin mutation: implications for interpreting reflection patterns.
X-ray diffraction from flight muscle with a headless myosin mutation: implications for interpreting reflection patterns.
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DOI：
10.3389/fphys.2014.00416
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发表时间：
2014
影响因子：
4
通讯作者：
Bernstein SI
中科院分区：
文献类型：
--
作者：
Iwamoto H;Trombitás K;Yagi N;Suggs JA;Bernstein SI
果蝇（Drosophila melanogaster）因其丰富的遗传资源而成为研究遗传病病因和影响的最有用的动物模型之一。它特别适合于研究由肌球蛋白突变引起的肌病，因为特异性突变可以诱导到飞行肌特异性肌球蛋白异构体，而其他异构体则保持完整。在这里，我们描述了一种基于x射线衍射的方法来评估果蝇间接飞行肌中收缩蛋白突变的结构效应。具体来说，我们描述了无头肌球蛋白突变Mhc10-Y97对x射线衍射图的影响，其中肌球蛋白头部的运动结构域被删除。从图中可以明显看出，长丝晶格整体完整性的丧失。然而，一个引人注目的观察结果是，在d = 14.5 nm处有明显的经向反射，这是含有肌球蛋白的粗丝规律性的标志。这种反射一直被认为主要来自肌凝蛋白头部，但以第6肌动蛋白层线反射作为内控，14.5 nm的反射甚至比野生型肌肉更强。我们通过电子显微镜证实了这些结果，其中图像分析显示具有类似周期性的结构。这些观察结果对肌球蛋白反射的解释具有重要意义。
Fruit fly (Drosophila melanogaster) is one of the most useful animal models to study the causes and effects of hereditary diseases because of its rich genetic resources. It is especially suitable for studying myopathies caused by myosin mutations, because specific mutations can be induced to the flight muscle-specific myosin isoform, while leaving other isoforms intact. Here we describe an X-ray-diffraction-based method to evaluate the structural effects of mutations in contractile proteins in Drosophila indirect flight muscle. Specifically, we describe the effect of the headless myosin mutation, Mhc10-Y97, in which the motor domain of the myosin head is deleted, on the X-ray diffraction pattern. The loss of general integrity of the filament lattice is evident from the pattern. A striking observation, however, is the prominent meridional reflection at d = 14.5 nm, a hallmark for the regularity of the myosin-containing thick filament. This reflection has long been considered to arise mainly from the myosin head, but taking the 6th actin layer line reflection as an internal control, the 14.5-nm reflection is even stronger than that of wild-type muscle. We confirmed these results via electron microscopy, wherein image analysis revealed structures with a similar periodicity. These observations have major implications on the interpretation of myosin-based reflections.
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影响因子：
5.6
作者：
HUXLEY, HE;BROWN, W
通讯作者：
BROWN, W
影响因子：
12.7
作者：
Lindqvist, Johan;Penisson-Besnier, Isabelle;Ochala, Julien
通讯作者：
Ochala, Julien
影响因子：
56.9
作者：
Iwamoto, H.;Yagi, N.
通讯作者：
Yagi, N.
DOI：
10.1098/rstb.2004.1557
发表时间：
2004-12-29
影响因子：
6.3
作者：
Lombardi, V;Piazzesi, G;Irving, M
通讯作者：
Irving, M
影响因子：
3.4
作者：
Miller, Mark S.;Farman, Gerrie P.;Maughan, David W.
通讯作者：
Maughan, David W.