Crystal Structure and Proteomics Analysis of Empty Virus-like Particles of Cowpea Mosaic Virus.
Crystal Structure and Proteomics Analysis of Empty Virus-like Particles of Cowpea Mosaic Virus.
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DOI：
10.1016/j.str.2016.02.011
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发表时间：
2016-04-05
期刊：
影响因子：
--
通讯作者：
Reddy VS
中科院分区：
文献类型：
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作者：
Huynh NT;Hesketh EL;Saxena P;Meshcheriakova Y;Ku YC;Hoang LT;Johnson JE;Ranson NA;Lomonossoff GP;Reddy VS
豌豆花叶病毒(CPMV)的空病毒样颗粒(EVLP)目前被用作各种生物医学和纳米技术应用的试剂。在这里，我们报道了用2.3°分辨率的X射线结晶学测定的CPMV eVLP的晶体结构，并与以前报道的eVLP和病毒粒子晶体结构的冷冻电子显微镜(Cryo-EM)进行了比较。尽管eVLP的X射线结构和冷冻-EM结构基本相似，但在小(S)亚单位的C端存在显著差异。S亚基的完整C末端在CPMV病毒粒子和eVLP的有效组装中起着关键作用，但在颗粒形成后经历蛋白质分解。此外，我们还报道了CPMVeVLP外壳蛋白亚基和病毒粒子的基于质谱学的蛋白质组学分析结果，这些结果表明S亚基的C末端发生了多个位点的蛋白水解性切割，而不是先前观察到的单一切割位点。
Empty virus-like particles (eVLPs) of Cowpea mosaic virus (CPMV) are currently being utilized as reagents in various biomedical and nanotechnology applications. Here, we report the crystal structure of CPMV eVLPs determined using X-ray crystallography at 2.3 Å resolution and compare it with previously reported cryo-electron microscopy (cryo-EM) of eVLPs and virion crystal structures. Although the X-ray and cryo-EM structures of eVLPs are mostly similar, there exist significant differences at the C terminus of the small (S) subunit. The intact C terminus of the S subunit plays a critical role in enabling the efficient assembly of CPMV virions and eVLPs, but undergoes proteolysis after particle formation. In addition, we report the results of mass spectrometry-based proteomics analysis of coat protein subunits from CPMV eVLPs and virions that identify the C termini of S subunits undergo proteolytic cleavages at multiple sites instead of a single cleavage site as previously observed.