CPMV-Based Expression Vector System Service
Creative BioMart Vir-Sci is an expert in both designing and engineering CPMV based expression vectors. By using highly optimized and standardized protocols, we permit high quality vectors used for efficient expression of exogenous proteins.
CPMV Based Expression System
Cowpea mosaic virus (CPMV) is the type member of the Comovirus family, which are characterized by a bipartite positive-strand RNA genome. RNA1 encodes essential proteins for replication whereas RNA2 consists of movement protein and coat proteins. When designing CPMV based expression vectors, RNA1 usually remains unchanged. Foreign proteins were firstly expressed as fusion proteins to the C terminus of coat or movement proteins. A proteolytic cleavage site was inserted in between to allow the cleavage of the target protein. However, replicating RNA virus-based expression strategy holds obvious disadvantages. On one hand, active virus may cause severe damage to the host plants, resulting in variations in the expression level or quality of the target proteins. On the other hand, the process of replication is error prone due to the poor fidelity of RNA-dependent RNA polymerases. The advent and wide use of agroinfiltration enable a novel nonreplicating expression strategy based on deconstructed RNA-2. Replacing the entire open reading frame of RNA-2 with GFP still allows successful replication of both RNAs. It is noteworthy that a suppressor of gene silencing should also be supplied because the natural CPMV suppressor of gene silencing is deleted. Further studies demonstrated that replication was not essential for expression from this kind of deconstructed vectors. Surprisingly, removing two upstream initiation codons dramatically elevates the expression level due to enhanced mRNA translation. This kind of vector, termed CPMV-hyper-translatable (CPMV-HT), have been widely used for the expression of valuable recombinant proteins.
Figure 1. Schematic diagram of the CPMV based expression vector.
Features of CPMV Based Vectors
- There is no obvious size limit of the gene that can be expressed.
- CPMV-HT and the suppressor of gene silencing can be expressed from a single T-DNA.
- Multiple proteins or peptides can be co-expressed.
- CPMV-HT allows high-level assembly of virus-like particles.
- The expression levels of individual proteins can be accurately manipulated by supplying constructs at different stoichiometries.
Service Advantages
- Rigorous design of CPMV-based vector
- Fast turnaround time
- High quality vectors with flexible production scale
- Strict QC testing to ensure correct sequences
- Competitive price in the market
Workflow of Construction of CPMV Based Expression Vectors
The expert team in Creative BioMart Vir-Sci will always find the best solution to your research goal. Please feel free to contact us for further questions.
References
- Hefferon, K. L. Plant virus expression vectors set the stage as production platforms for biopharmaceutical proteins. Virology, 2012, 433(1): 1-6.
- Peyret, H.; Lomonossoff, G. P.; When plant virology met Agrobacterium: the rise of the deconstructed clones. Plant biotechnology journal, 2015, 13(8): 1121-1135.