Plasmid-Mediated Transient Mammalian Protein Expression

Transferring the foreign segment into mammalian cells by plasmid vector is a common biological technique. In addition to the conveniently operated transfection procedure, high transfection efficiency has also been observed in wide ranges of host cells. Therefore, the plasmid-mediated mammalian protein expression system is still the preferred method in most laboratories although many advanced virus-based transient vector types have emerged in recent years (such as baculovirus vectors and adenovirus vectors).

Plasmid Elements and Properties

• Non-integration plasmid: The plasmid vector is used to mediate transient expression because the fraction of stable integration into the cell genome is less than 1%.
• Vary transfection efficiency to different cell types: Due to the varied transfection efficiency, we recommend dividing and immortalizing cell lines as the host cell.
• Easily operated procedure: The process of delivering plasmid vector into mammalian cells by plasmid is more straightforward than that of virus-mediated system. There is no need to prepare for live virus vector packaging.
• Large vector capacity: The total capacity of our vector is up to 30 KB, of which the plasmid skeleton is only 3 KB, which has enough capacity to place customers' sequences of interest.
• High-level expression: The vector is engineered to produce a high post-transfection copy number in the host cell (up to thousands of copies per cell) so that foreign genes can be expressed at a high level.
• Marker: The marker sequence can be either a resistance gene, a fluorescent gene, or a dual-reporter gene, allowing cells transduced with the vector to be selected and/or visualized.

Service Content

Selection of expression integration
Available plasmid vector Creative BioMart's original improved vector (vector can be selected and/or visualized based on the marker gene on the plasmid). Other common commercial vectors		Available host cells Dividing and immortalizing cell lines are recommended (we will choose adherent or suspension cells according to the requirement). Other commercial cell lines
Expression vector construction	Timeline	Deliverable
Codon optimization Subclone Endotoxin-free Plasmid Extraction	3-4 weeks	Target DNA synthesis report Sequencing report E. coli DH10 that contains expression vector Expression plasmid vector
Small-scale transfection test
Transient transfection Small-scale expression test Product analysis (WB)	2-3 weeks	Expression analysis report
Expression and purification
200 ml scale expression Affinity purification Identification and detection of recombinant protein	1-2 weeks	Protein sample
Scale-up and protein purification
Scale-up according to the requirement Affinity purification PAGE assay Product delivery	2-5 weeks	Protein QC report Protein product

Note: We will optimize the target sequence according to the codon preference of the chosen host cell, and optimize the motif, repeat sequence, GC content and the secondary structure of mRNA. We can add secretory signal peptide or label to the expression vector to promote the secretion and expression of the target protein, which is easy to purify.

For any questions, requests, or further information, please feel free to contact us or submit an online inquiry. Creative BioMart's 24/7 customer service will always be there for you.