Truncated Bovine Integrin Alpha-v/Beta-6 as a Universal Capture Ligand for FMD Diagnosis
PLOS ONE
Authors: Shimmon, Gareth; Wood, Britta A.; Morris, Alison; Mioulet, Valerie; Grazioli, Santina; Brocchi, Emiliana; Berryman, Stephen; Tuthill, Toby; King, Donald P.; Burman, Alison; Jackson, Terry
Abstract
Foot-and-mouth disease (FMD) is endemic in many regions of the world and is one of the most prevalent epizootic animal diseases. FMD affects livestock, such as cattle, sheep, goats and pigs, and causes enormous economic losses due to reduced productivity and trade restrictions. Preparedness and early diagnosis are essential for effective control of FMD. Many diagnostic assays are dependent on raising high-affinity, anti-FMD virus (FMDV) serotype-specific antibodies in small animals (rabbits and guinea pigs) that give broad virus coverage. Here we show that soluble, truncated forms of bovine alpha v beta 6 bind FMDV in an authentic RGD and divalent cation dependent interaction and can be used as the trapping reagent in a FMDV sandwich ELISA. In addition, inclusion of FLAG or His tags facilitates simple purification without the loss of virus binding. We also provide evidence that when combined with a guinea pig polyclonal serum, or serotype-specific monoclonal antibodies, the integrin can be used to detect viruses representative of all FMDV serotypes. We also show that recombinant FMDV empty capsids, with stabilising disulphide bonds, can serve as an antigen in the ELISA and can therefore replace inactivated virus antigen as a positive control for the assay. Our results demonstrate the potential use of bovine alpha v beta 6 and FMDV empty capsids in FMD diagnostic assays.
High-performance gene expression and knockout tools using sleeping beauty transposon system
MOBILE DNA
Authors: Hu, Kaishun; Li, Yu; Wu, Wenjing; Chen, Hengxing; Chen, Zhen; Zhang, Yin; Guo, Yabin; Dong, Yin
Abstract
BackgroundSimilar to retro-/lenti- virus system, DNA transposons are useful tools for stable expression of exogenous genes in mammalian cells. Sleeping Beauty (SB) transposon has adopted for integrating genes into host genomes in recent studies. However, SB-derived vector system for proteins purifying/tracking and gene knockout are still not available.ResultsIn this study, we generated a series of vectors (termed as pSB vectors) containing Sleeping Beauty IRDR-L/R that can be transposed by SB transposase. Gateway cassette was combined to the pSB vectors to facilitate the cloning. Vectors with various tags, Flag, Myc, HA, V5 and SFB, were generated for multiple options. Moreover, we incorporated the CRISPR-Cas9 cassette into the pSB plasmids for gene knockout. Indeed, using one of these vectors (pSB-SFB-GFP), we performed Tandem Affinity Purification and identified that NFATc1 is a novel binding partner of FBW7. We also knocked out RCC2 and BRD7 using pSB-CRISPR vector respectively, and revealed the novel roles of these two proteins in mitosis.ConclusionOur study demonstrated that the pSB series vectors are convenient and powerful tools for gene overexpression and knockout in mammalian cells, providing a new alternative approach for molecular cell biology research.