and make the shRNA expression vector for you based on a set of widely
accepted design rules and additional proprietary rules. We generally have 50%
success rate in obtaining siRNA sequence that have 70% percent “knock-
down” efficiency. However, because the functionality of the selected siRNA
target sequences can only be determined empirically, we offer a service
guarantee to the users who order three constructs to be made for each target
gene. See in "terms and conditions" for detail.
conditions listed on the ordering page. Submitting an order form is construed as
you have carefully read and agree with such terms and conditions.
Purchase of the shRNA vector Design & Construction service amounts to entering a
service agreement under which Cellogenetics is contractually obligated to:
1. design a requested number of shRNA target sequences based on a set of
widely accepted design rules and proprietary design rules. We generally have 50%
success rate in obtaining shRNA sequences that have 70% percent “knock-down”
efficiency. However, because the functionality of the shRNA target sequences can
only be determined empirically, we offer a "Service Guarantee*" to any purchase
of three or more constructs to be made for each target gene.
2. synthesize the corresponding DNA oligoes for and generate the ordered shRNA
expression constructs.
3. confirm the cloned shRNA coding sequence by DNA sequencing.
4. make glycerol stocks of bacterial clones containing the ordered shRNA
expression constructs and prepare technical spec sheet.
5. ship the ordered shRNA expression constructs as glycerol stocks along with all
pertinent technical information within 15 business days from the date when the
order was placed.
* "Service Guarantee"
Cellogenetics' Service Guarantee applies to any purchase of three shRNA
constructs for each target gene to be designed and constructed by Cellogenetics.
During one year from the date when the constructs were sent, Cellogenetics
guarantees that at least one of the three shRNA constructs will generate 70%
percent “knock-down” or higher efficiency over the target protein or mRNA as either
tested individually or collectively in a pool in transfection experiments. The "knock-
down" efficiency is defined as percentage reduction in expression level of target
protein or mRNA produced from a co-transfected cDNA plasmid in the above
experiment using either protein assay, or functional reporter assay, or RNA assay.
In the event that none of the three constructs surpasses the 70% "knock-down"
efficiency, Cellogenetics agrees to re-design and generates additional shRNA
expression constructs for the same target gene free of charge. For this guarantee,
Cellogenetics reserves the right to be shown reasonable "proof of failure", which
can be the results from any of the above assays or the combination thereof.
vector designed to express double stranded small hairpin RNA
(shRNA) from the human U6 snRNA promoter. There are four base
changes between the +1 site (G) and the TATA box in the human U6
promoter inserted in pLenti-hU6BX. Mutagenesis studies reported in
the literature indicate that these four bases are not conserved and
that the alteration shown here would not affect transcription
efficiency.
All pLenti-hU6BX derived plasmids should be propagated in suitable
host strains such as DH5a, or HB101, under selection of resistance to
ampicillin (50 ug/ml). E.coli replication origin: pUC; copy number:
high.
Infectious viral particles should be obtained from 293T cells by
co-transfection with helper plasmids: delta8.9 (gag/pol) and vsv-g
(pseudotyping plasmid), with the Virapower packaging mix
(K4970-00, InVitrogen).
