Frequently Asked Questions
The Modern Vector represents a complete redesign of both the backbone and individual features.
Dozens of changes went into the creation of the Modern Vector. It is the culmination of thousands of hours of modification, followed by testing, to verify each improvement.
- We removed substantial amounts of legacy sequence that is no longer useful with modern techniques.
- We optimized the placement and sequence of each feature to maximize its value for your work.
- We inserted restriction sites at critical points in the vector to allow you to insert homology arms or any other sequence you want.
- All of this in a vector that is only 30% larger than pUC19.
The Modern Vector: Sleek, Powerful, Efficient
The resistance marker is coupled for selection in both prokaryotes and eukaryotes.
One of the major redesigns of the Modern Vector was to create a single resistance marker for both prokaryotes and eukaryotes. This meant that the antibiotic resistance had to work in both prokaryotes and eukaryotes, a high hurdle.
Through our testing, we identified that Blasticidin S and Puromycin are effective in both hosts.
We were also able to modify the Neomycin resistance gene so that it became effective for resistance to Kanamycin, yet still worked for G418 selection.
This gives you 3 different resistance markers to choose from.
Our lab continues to test for new antibiotic options for use in both prokaryotes and eukaryotes. We will release new vectors as soon as we are able.
You may see differences in the bacterial growth, particularly on solid medium
Since Blasticidin S and Puromycin have not been traditionally used for bacterial selection, you may notice differences in the growth of bacteria.
It can take a little while longer to kill the non-transformed bacteria, so you may see more "lawn". However, the resistant colonies will stand out and are the only bacteria that will divide in liquid culture.
There may be differences in the sensitivity of the different strains of bacterial hosts, so if this is an issue, spread less of the transformation on each plate.
Homology arms are critical for targeting for gene "knock in".
During either homologous recombination, for example in murine ES cells, or for certain types of genomic editing, using CRISPR for instance, it is critical to include regions of sequence homology that is identical to the targeted region. Approximately 500-1500 bases of sequence (the homology arms), on each side of the point of interest needs to be included for efficient targeting.
These homology arms allow for specific targeting to the genome and as such should be as unique as possible. For CRISPR and other genomic editing techniques, (TALEN and Zinc Finger nucleases, are two additional examples) the homology arms need to be as close as possible to the site of cleavage. While there are no specific "rules" for how long the homology arms must be to be effective, there is general consensus that 0.5-1.5Kb is sufficient for each side.
Since the "knock in" will occur between the two arms, BLAST the proposed sequences of the homology arms to ensure they are unique to the region you want, so you want to avoid repeats as much as possible.
While one feature is its small size, the Modern Vector has dozens of other improvements to make your work easier.
On its face, the first feature of the Modern Vector is certainly is small size. While that may seem trivial, if you want to add multiple ORFs, extra regulatory sequence, or just about anything else, having more sequence to work with is critical.
But it isn't just efficient in its sequence, the features in the Modern Vector were rationally designed to work together to support your efforts.
For example:
- Having sequence regions specifically designed for insertion of homology arms at optimal locations makes genomic editing "knock ins" much easier to build.
- The design and inclusion of an artificial intron increases the stability of the RNA transcripts, which can result in additional protein expression. Most synthetic genes of interest are cDNA, so they lose this valuable RNA stabilizing motif.
- Unique restriction sites have been positioned at the junctions of nearly all the features allowing you to modify nearly every one. Don't like the main promoter, change it. Want a different origin of replication, no problem. No other vector makes customization as easy as the Modern Vector.
Expression was tested in multiple challenges.
Here is some data on expression using the Modern Vector compared to a popular legacy vector that is also commercially available.
In all cases the cDNA insert is identical between the two constructs. Selection, when done, was identical for the two constructs. Data represents typical results of 3 or more experiments.
Head to head, with a small, cytosolic protein, the Modern Vector greatly outperforms the legacy vector.
With less sequence, the Modern Vector is far more consistent at stable integration. Get the clones you need without having to worry as much about false positives.
Big, complicated proteins can be hard to express, but the Modern Vector handles them with ease. The smaller backbone size increases stability in bacterial hosts and expression is still top notch.
While an excellent general protein expression vector, the Modern Vector came out of work for a cell based therapy and here it really shines. Targeted integration is the gold standard for genomic editing and the Modern Vector was far better (up to 50% in some difficult cases) than the legacy vector. Plus, with dedicated restriction sites to insert the homology arm sequence, it is a snap to build.