Mouse KLF4 Lentivirus, Full-length Gene in Lentivector, Pre-packaged Lentiviral Particles
KLF4 (Krueppel-like factor 4), also known as EZF (Epithelial zinc finger protein) and GKLF (Gut-enriched krueppel-like factor), belongs to the krueppel C2H2-type zinc-finger protein family. In addition to 3 C2H2-type zinc fingers responsible for DNA binding, KLF4 contains a 9aa-TAD (transactivation domain) motif that is found in a large number of yeast and animal transcription factors. KLF4 is a transcription factor that can act both as activator and as repressor. It recognizes a 5'-CACCC-3' core sequence. KLF4 binds to the promoter region of its own gene to activate its own transcription. KLF4 contributes to the down-regulation of p53/TP53 transcription and regulates the expression of key transcription factors during embryonic development. KLF4 plays an important role in maintaining embryonic stem (ES) cells , and in preventing their differentiation. KLF4 is equired for establishing the barrier function of the skin and for postnatal maturation and maintenance of the ocular surface. KLF4 is involved in the differentiation of epithelial cells and may also function in skeletal and kidney development. It is also implicated in multiple cancer types. OCT4, SOX2, c-Myc and KLF4 are the 4 reprogramming factors that together are sufficient to reprogram differentiated cells to an embryonic-like state termed iPS (induced pluripotent stem) cells. iPS cells exhibit the morphology and growth properties of ES cells and express ES cell marker genes. The pre-packaged lentiviral particles can be transduced into any mammalian cell type for constitutively and stably expressing mouse KLF4.
Gene Symbol: KLF4; EZF; GKLF
NCBI Gene ID: 16600
Uniprot Entry: Q60793
Construct Details: Full length mouse KLF4 gene (UniProt #Q60793) is subcloned into the Lentiviral expression vector pLTE with an upstream EF1α promoter and with or without a selection marker, which can be used for both transient and stable expression in mammalian cells. It can be co-transfected with the LentiPAK DNA mix (SKU# LP-001) into HEK293 cells to produce high titer lentiviral particles.
Vector Type: pLTE or pLTE-IRES-Marker (lentiviral expression vector containing a heterologous EF1α promoter which is active in both human and murine cells, see the vector map above)
Gene Insert Size: 1452 (bp)
Gene Insert Sequence:
ATGAGGCAGCCACCTGGCGAGTCTGACATGGCTGTCAGCGACGCTCTGCTCCCGTCCTTCTCCACGTTCGCGTCCGGCCC
GGCGGGAAGGGAGAAGACACTGCGTCCAGCAGGTGCCCCGACTAACCGTTGGCGTGAGGAACTCTCTCACATGAAGCGAC
TTCCCCCACTTCCCGGCCGCCCCTACGACCTGGCGGCGACGGTGGCCACAGACCTGGAGAGTGGCGGAGCTGGTGCAGCT
TGCAGCAGTAACAACCCGGCCCTCCTAGCCCGGAGGGAGACCGAGGAGTTCAACGACCTCCTGGACCTAGACTTTATCCT
TTCCAACTCGCTAACCCACCAGGAATCGGTGGCCGCCACCGTGACCACCTCGGCGTCAGCTTCATCCTCGTCTTCCCCGG
CGAGCAGCGGCCCTGCCAGCGCGCCCTCCACCTGCAGCTTCAGCTATCCGATCCGGGCCGGGGGTGACCCGGGCGTGGCT
GCCAGCAACACAGGTGGAGGGCTCCTCTACAGCCGAGAATCTGCGCCACCTCCCACGGCCCCCTTCAACCTGGCGGACAT
CAATGACGTGAGCCCCTCGGGCGGCTTCGTGGCTGAGCTCCTGCGGCCGGAGTTGGACCCAGTATACATTCCGCCACAGC
AGCCTCAGCCGCCAGGTGGCGGGCTGATGGGCAAGTTTGTGCTGAAGGCGTCTCTGACCACCCCTGGCAGCGAGTACAGC
AGCCCTTCGGTCATCAGTGTTAGCAAAGGAAGCCCAGACGGCAGCCACCCCGTGGTAGTGGCGCCCTACAGCGGTGGCCC
GCCGCGCATGTGCCCCAAGATTAAGCAAGAGGCGGTCCCGTCCTGCACGGTCAGCCGGTCCCTAGAGGCCCATTTGAGCG
CTGGACCCCAGCTCAGCAACGGCCACCGGCCCAACACACACGACTTCCCCCTGGGGCGGCAGCTCCCCACCAGGACTACC
CCTACACTGAGTCCCGAGGAACTGCTGAACAGCAGGGACTGTCACCCTGGCCTGCCTCTTCCCCCAGGATTCCATCCCCA
TCCGGGGCCCAACTACCCTCCTTTCCTGCCAGACCAGATGCAGTCACAAGTCCCCTCTCTCCATTATCAAGAGCTCATGC
CACCGGGTTCCTGCCTGCCAGAGGAGCCCAAGCCAAAGAGGGGAAGAAGGTCGTGGCCCCGGAAAAGAACAGCCACCCAC
ACTTGTGACTATGCAGGCTGTGGCAAAACCTATACCAAGAGTTCTCATCTCAAGGCACACCTGCGAACTCACACAGGCGA
GAAACCTTACCACTGTGACTGGGACGGCTGTGGGTGGAAATTCGCCCGCTCCGATGAACTGACCAGGCACTACCGCAAAC
ACACAGGGCACCGGCCCTTTCAGTGCCAGAAGTGTGACAGGGCCTTTTCCAGGTCGGACCACCTTGCCTTACACATGAAG
AGGCACTTTTAA
Formulation: Pre-packaged lentiviral particles in the conditional medium (serum-free) from HEK293 cells (typical titer 106 - 107 IFU/ml)
FOR RESEARCH USE ONLY. NOT FOR DIAGNOSTIC OR THERAPEUTIC USE IN HUMAN.
Important Safety Information: With the safety features in place, our lentiviral vectors and viral particles can be employed in standard Biosafety Level 2 tissue culture facilities and should be treated with the same level of caution as any other potentially infectious agent. Any investigator who purchases our lentiviral/retroviral products & services is responsible for following Biosafety Level 2 requirements on the handling of viral particles. For more information on Biosafety Level 2 agents and practices, please refer to NIH’s “Biosafety Considerations for Research with Lentiviral Vectors”.
Restriction: This product is not transferable or re-sellable. Customer obtain no right to transfer, assign, or sublicense its use rights, or to transfer, resell, package, or otherwise distribute the product, or to use the product for the benefit of any third party or for any commercial purpose. Customer may only use the product in compliance with applicable local, state and federal laws, regulations and rules. Customer may not directly or indirectly use the product or allow the transfer, transmission, export or re-export of all or any part of the product in violation of any export control law or regulation of the united states or any other relevant jurisdiction. Your use of this product constitutes acceptance of the terms of this limited use agreement. Please refer to our “terms & conditions” for details. If you are not willing to accept the limitation of this agreement, G&P Biosciences will accept return of the product for a full/partial refund.
Pre-packaged lentiviral particles are most advanced gene delivery tools. Each particles contain a fully sequence verified target gene and are psudotyped with the VSV-G glycoprotein, ready for transduction into into a wide range of cell types including hard-to-transfect primary cells and non-dividing cells. They are supplied in 1-mL aliquot(s) of the serum-/antibiotic-free solution suitable for both in vitro and in vivo delivery. They are produced in HEK293 packaging cells with a typical titer of ≥107 IFU/ml using our optimized LentPAKTM packaging system. The lentiviral particles can be used to transduce subconfluent target cells. Depending on your purpose, you may choose a specific multiplicity of infection (MOI) or test a range of MOIs to determine which gives you the desired results. Transduction can be enhanced by the addition of polybrene, also known as hexadimethrine bromide (typically at 8-10 μg/ml).
Quick Protocol for Transduction
Day 1. Seeding Target Cells
For an example, plate target cells in a 10 cm plate at a density of 1 - 5x 105 cells/ml that will produce approximately 60% confluency in 24 hours.
Note: other size plates can also be used depending on the nature of your experiment. Adjust the reagent amount according to Table 1
Table 1. Seeding Density of Target Cells (1 day prior to transduction)
Vessel Type |
Seeding Target Cell# |
Volume of Media |
10-cm dish |
1 – 5 x 106 |
10 mL |
6-well plate |
0.3 – 1 x 106 |
2 mL/well |
12-well plate |
0.15 – 0.5 x 106 |
1 mL/well |
24-well plate |
0.6 – 2 x 105 |
0.5 mL/well |
96-well plate |
1 – 4 x 104 |
0.1 mL/well |
Day 2. Transduction
Remove the growth media from the dish/plate prepared the day before. Replace with 1/2 volume of culture medium containing desired amount of lentiviral particles (at 2 to 20 MOI). For example, add 4.5 mL of growth medium and 0.5 mL of Lentiviral particles, or simply add 5 mL of Lentiviral particles (for a low titer viral preparation or a high MOI transduction). Add polybrene directly to the media on the target cells at 8 μg/ml. Mix by gentle swirling.
Incubate at 37°C with 5% CO2 for 4 - 24 hours, then replace the transduction medium with right amount of growth medium according to table 1 (for example 10 mL for 10-cm dish). Culture the cells for 48 – 72 hours, and transduced cells are ready for downstream analyses.
Note: Adjust volumes accordingly for transduction of other plate types. For example, add 1 ml of growth medium and lentiviral particle mixture for 6-well plate, 0.5 ml for 12-well and 0.25 mL for 24-well except for 96 well, in which 100 μl should be used. The change of transduction medium is often unnecessary with our pre-packaged lentiviral particles. Simply culture cells for 3-4 days before analysis.
The virus-containing media can be changed in as short as 4 hours after transduction if toxicity of the lentiviral transduction is a concern. Normally reverse transcription and genome integration of the lentivector takes place within 24-36 hours. With our ready-to-use, prepackaged lentiviral particles, the change of media is often unnecessary. The transduction process can be ongoing for 2 - 6 days without significant impact on cell growth/viability. The transduction process can also be repeated if desired. For a lentivector with a fluorescent reporter (such as GFP), FACS can be used to enrich for cells that express GFP. If it contains a drug selectable marker, follow the protocol for the particular drug. For example, puromycin selection is usually carried out at 1-10 μg/mL, depending on the target cells’ sensitivity
Important Safety Information
With the safety features in place, our lentiviral vectors and viral particles can be employed in standard Biosafety Level 2 tissue culture facilities and should be treated with the same level of caution as any other potentially infectious agent. Any investigator who purchases our lentiviral/retroviral products & services is responsible for following Biosafety Level 2 requirements on the handling of viral particles. For more information on Biosafety Level 2 agents and practices, please refer to NIH’s “Biosafety Considerations for Research with Lentiviral Vectors”.
Poor Transduction Efficiency:
Poor transduction efficiency could be due to a low viral titer. While lentivectors can accommodate relatively large inserts (up to 8 kb) comparing to other systems, there is still a packaging limit. In general, lentivectors could transfer up to 8-kb gene inserts. However, any gene insert larger than 4kb will dramatically decreases packaging efficiency, which would results in a lower viral titer. To overcome low titers, concentrate viral particles or lower target cell density for transduction. If the transduction efficiency is low despite a high titer of virus, the total volume of transduction media on the target cells may be too high. Transduction can be carried out in a volume of media that just covers the cells; this may increase the exposure of the cells to the virus. Low speed spin (e.g., 1500 rpm for 15-30 min) may help increase the likelihood of virus-cell interactions. Pseudotyping of the transducing virus to target more abundant receptors on a particular cell type is another potential approach.
Transduction Kills Target Cells:
It is possible that MOI may be too high. Perform the transduction with a lower MOI or less viral particles. Packaging cell medium may not be compatible for target cell growth. Either dilute the virus in target cell-compatible medium or concentrate and resuspend the virus in medium compatible with the target cell growth. Change the transduction media containing the virus as early as 4 hrs after transduction.
FOR RESEARCH USE ONLY. NOT FOR DIAGNOSTIC OR THERAPEUTIC USE IN HUMAN.
The product is shipped at 4°C for immediate use. Upon receipt, centrifuge the vial briefly before opening. Store at –80°C or lower and the product is stable for 3 months. Avoid repeated freeze-thaw cycles.
The product should be employed in a Biosafety Level 2 tissue culture facility.
FOR RESEARCH USE ONLY. NOT FOR DIAGNOSTIC OR THERAPEUTIC USE IN HUMAN.
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2. Cell Growth Differ. 10:423 (1999)
3. Genomics 89:756 (2007)
4. Cell 131:861 (2007)
5. J. Biol. Chem. 285:9180 (2010)
6. FASEB J. 27:432 (2013)
Product datasheet (pdf) can be downloaded here: LEV0022-PDS.pdf
Additional supporting documents, including COA and MSDS are available upon request.
FOR RESEARCH USE ONLY. NOT FOR DIAGNOSTIC OR THERAPEUTIC USE IN HUMAN.
Restriction: This product is not transferable or re-sellable. Customer obtain no right to transfer, assign, or sublicense its use rights, or to transfer, resell, package, or otherwise distribute the product, or to use the product for the benefit of any third party or for any commercial purpose. Customer may only use the product in compliance with applicable local, state and federal laws, regulations and rules. Customer may not directly or indirectly use the product or allow the transfer, transmission, export or re-export of all or any part of the product in violation of any export control law or regulation of the united states or any other relevant jurisdiction. Your use of this product constitutes acceptance of the terms of this limited use agreement. Please refer to our “terms & conditions” for details. If you are not willing to accept the limitation of this agreement, G&P Biosciences will accept return of the product for