Piranha™ Targeted Protein Degradation
Electroporation-ready mRNA

Quickly knock-down protein activity using Piranha Electroporation-ready mRNA – robust, targeted protein degradation.

Catalog Number
Add to Cart

Piranha™ Electroporation-Ready mRNA

10 µg
$ 295

Piranha™ Electroporation-ready RFP-tagged mRNA

10 µg
$ 325

Piranha™ Electroporation-ready GFP-tagged mRNA

10 µg
$ 325
Contact Us Speak to a specialist


Faster insights into protein function in vivo

Quickly and directly study the role a protein plays in vivo with SBI’s Piranha Targeted Protein Degradation System, Electroporation-ready mRNA. After electroporating both the Piranha mRNA and an antibody specific for your protein-of-interest into target cells, you can start seeing degradation of the protein-of-interest in as little as 1 hour*. Piranha Electroporation-ready mRNA is available in untagged, RFP-tagged, or GFP-tagged versions (also available as Pre-packaged Lentivirus or HEK293T Stable Cell Line).

While studying protein function in vivo often involves knocking down expression using siRNA or knocking out the gene via CRISPR/Cas9, these approaches are indirect and often imperfect. siRNA can reduce or eliminate protein expression, but if the protein turn-over rate is slow then it can take days to see a reduction in function. Simply knocking out the gene coding for the protein-of-interest is not always possible, limits the type of studies you can do, and is incompatible with essential genes. To give researchers another faster option, SBI developed the Piranha Targeted Protein Degradation System.

  • Specific—avoid off-target effects associated with genomic-based approaches (CRISPR/Cas9) or mRNA targeting (RNAi) by directly targeting the protein-of-interest
  • Fast—observe protein degradation in as little as 1 hour* for speedier, more efficient studies
  • Simple—relies on only two reagents, the Piranha System and your validated antibody
  • Powerful—antibody-based targeting means the Piranha System can selectively degrade the phosphorylated or other post-translationally modified form of a protein while leaving the unmodified form intact
  • Scalable for screening—use either the HEK293T Piranha Cell Line or your own cell line stably expressing Piranha protein to evaluate multiple protein targets in parallel (96- or 384-well plate assays)
  • Unique—the only commercially available system for direct targeted degradation of protein(s)-of-interest for phenotypic studies
  • Flexible—available as electroporation-ready mRNA, constitutively expressed in a HEK293T cell line, or as pre-packaged lentivirus for stable Piranha expression in the cell line of your choice

*Based on published data by Clift et al. A Method for the Acute and Rapid Degradation of Endogenous Proteins. Cell. 2017 Dec 14;171(7):1692-1706.e18. doi: 10.1016/j.cell.2017.10.033.  Degradation rate of target protein and resulting phenotypic effects will depend on the specific protein being targeted and influenced by protein degradation pathway and any compensatory mechanisms.  An initial time course experiment to find optimal conditions to assay for protein knockdown and phenotypes is highly recommended.

Available Piranha Targeted Protein Degradation System Products


Table 1. Available Piranha Targeted Protein Degradation System Products

Cat. #Product
Electroporation-ready mRNA
PTPD500A-1Piranha Electroporation-ready untagged mRNA
PTPD510A-1Piranha Electroporation-ready RFP-tagged mRNA
PTPD520A-1Piranha Electroporation-ready GFP-tagged mRNA
Stable Cell Line
PTPD600A-1Piranha HEK293T GFP/Puromycin Stable Cell Line
Pre-packaged Lentivirus
PTPD513VA-1pCDH-CMV-Piranha-EF1-GFP-T2A-Puro Pre-packaged Lentivirus
PTPD527VA-1pCDH-EF1a-Piranha-T2A-Puro Pre-packaged Lentivirus

How It Works

Targeted Protein Degradation with Piranha

SBI’s Piranha Targeted Protein Degradation System is based on the TRIM21 pathway found in most mammalian cells1 (Figure 1). Like TRIM21, the Piranha protein binds to conserved regions of an antibody, targeting the antibody—and the bound antigen—for degradation by the proteasome.

How the Piranha Targeted Protein Degradation System works

To use Piranha Electroporation-ready mRNA for targeted protein degradation, simply electroporate the Piranha mRNA and a validated antibody specific for the protein-of-interest into target cells, wait an appropriate amount of time, and then observe the phenotypic outcome. Because the rate of protein degradation is based upon many factors, we recommend performing initial experiments to empirically determine the degradation rate of your target protein and the optimal time for phenotypic observation.

1. Clift D, et al. A Method for the Acute and Rapid Degradation of Endogenous Proteins. Cell. 2017 Dec 14;171(7):1692-1706.e18. doi: 10.1016/j.cell.2017.10.033.

Supporting Data

See the Piranha Targeted Protein Degradation System in action

Piranha Electroporation-ready mRNA is pure and efficiently delivered and translated inside cells

Figure 2. Piranha Electroporation-ready mRNA is pure and efficiently delivered and translated inside cells. (A) Denaturing RNA gel electrophoresis of Piranha RFP-tagged, untagged, and GFP-tagged mRNA shows clean transcripts of an appropriate size. (B) Fluorescence imaging of HEK293T cells electroporated with Piranha RFP-tagged mRNA shows robust delivery and translation of the construct.

Double Reporter Piranha HEK293T Cells electroporated with anti-IKKα antibody show complete and near-complete ablation of IKKα after one day

Figure 3. Piranha HEK293T Cells electroporated with anti-IKKα antibody show complete and near-complete ablation of IKKα after one day. A validated anti-IKKα antibody was electroporated into Piranha HEK293T cells using two different conditions (A and B), and IKKα protein levels assessed via Western blot and compared to a no-construct control. On day 1 post-electroporation, condition A shows complete ablation of IKKα protein and condition B shows almost complete ablation. By Day 2 levels of IKKα protein begin to return to pre-electroporation levels as the amount of antibody dissipates.

Piranha mRNA and antibody efficiently reduce protein levels at a faster rate than corresponding siRNA

Figure 4. Piranha mRNA and antibody efficiently reduce protein levels at a faster rate than corresponding siRNA. Piranha mRNA and validated anti-IκBα antibody were co-electroporated into HeLa cells (top panel) and IκBα protein levels monitored over time via Western blot. Compared to IκBα levels after introduction of IκBα siRNA (bottom panel), the Piranha System reduces IκBα protein levels faster—reduction is apparent by 8 hours (top panel), whereas for siRNA protein reduction is first apparent only after 24 hours (bottom panel).

The speed of the Piranha System is also evident using a luciferase-based activity assay

Figure 5. The speed of the Piranha System is also evident using a luciferase-based activity assay. MDA-MB-231 breast cancer cells were co-electroporated with Piranha mRNA and anti-IκBα antibody, and IκBα activity measured using an NFκB luciferase reporter assay—lower IκBα levels result in higher NFκB luciferase reporter activity. Compared to reduction of IκBα activity by siRNA (dark gray bars), which peaks on day 2, the Piranha System shows peak reduction of IκBα activity on day 1 (blue bars). The negative control is shown as light gray bars.

The Piranha System can reduce levels of phosphorylated protein

Figure 6. The Piranha System can reduce levels of phosphorylated protein. Piranha HEK293T Cells were electroporated with either buffer only (NC), anti-phospho-AKT(S473) antibody, or an IgG control, and total AKT levels assessed via Western blot.  Within 5-hrs post-electroporation, both phosphorylated and total AKT protein levels are reduced.


  • Akerman, AW, et al. (2019) Elevated Wall Tension Leads to Reduced miR-133a in the Thoracic Aorta by Exosome Release. J Am Heart Assoc. 2019 Jan 8; 8(1):e010332. PM ID: 30572760
  • Shao, Y, et al. (2019) Overexpression of CXCR7 promotes mesenchymal stem cells to repair phosgene-induced acute lung injury in rats. Biomedicine & Pharmacotherapy. 2019 Jan 1; 109:1233-1239. Link: Biomedicine & Pharmacotherapy
  • Wang, Z, et al. (2019) Nucleophosmin Phosphorylation as a Diagnostic and Therapeutic Target for Ischemic AKI. J. Am. Soc. Nephrol.. 2019 Jan 1; 30(1):50-62. PM ID: 30573638
  • Xu, L, et al. (2018) MiR-34c ameliorates neuropathic pain by targeting NLRP3 in a mouse model of chronic constriction injury. Neuroscience. 2018 Dec 26;. PM ID: 30593918
  • Sekiba, K, et al. (2018) Pevonedistat, a first-in-class NEDD8-activating enzyme inhibitor, is a potent inhibitor of hepatitis B virus. Hepatology. 2018 Dec 26;. PM ID: 30586159
  • Foerster, F, et al. (2018) Enhanced protection of C57 BL/6 vs Balb/c mice to melanoma liver metastasis is mediated by NK cells. Oncoimmunology. 2018 Dec 26; 7(4):e1409929. PM ID: 29632723
  • Qi, S, et al. (2018) MCPIP1 mediates inflammatory responses induced by lipopolysaccharide and lipoteichoic acid in bovine mammary epithelial cells. Acta Biochim. Biophys. Sin. (Shanghai). 2018 Dec 26;. PM ID: 30590418
  • Hino, N, et al. (2018) An amphipathic helix of vinexin α is necessary for substrate stiffness-dependent conformational change in vinculin. J. Cell. Sci.. 2018 Dec 21;. PM ID: 30578314
  • Wang, J, et al. (2018) Determination of Serum Exosomal H19 as a Noninvasive Biomarker for Bladder Cancer Diagnosis and Prognosis. Med. Sci. Monit.. 2018 Dec 21; 24:9307-9316. PM ID: 30576305
  • Ren, F, et al. (2018) The R132H mutation in IDH1 promotes the recruitment of NK cells through CX3CL1/CX3CR1 chemotaxis and is correlated with a better prognosis in gliomas. Immunol. Cell Biol.. 2018 Dec 21;. PM ID: 30575118
  • Xie, Y, et al. (2018) Molecular network of miR-1343 regulates the pluripotency of porcine pluripotent stem cells via repressing OTX2 expression. RNA Biol. 2018 Dec 20;. PM ID: 30567463
  • Raffo-Romero, A, et al. (2018) Medicinal Leech CNS as a Model for Exosome Studies in the Crosstalk between Microglia and Neurons. Int J Mol Sci. 2018 Dec 19; 19(12). PM ID: 30572617
  • Zhang, J, et al. (2018) Mouse serum protects against total body irradiation-induced hematopoietic system injury by improving the systemic environment after radiation. Free Radic. Biol. Med.. 2018 Dec 19; 131:382-392. PM ID: 30578918
  • Saeed, U, et al. (2018) Parvulin 14 and parvulin 17 bind to HBx and cccDNA and upregulate HBV replication from cccDNA to virion in a HBx-dependent manner. J. Virol.. 2018 Dec 19;. PM ID: 30567987
  • Rostami, M, Haidari, K & Shahbazi, M. (2018) The Human IL-23 Decoy Receptor Inhibits T-Cells Producing IL-17 by Genetically Engineered Mesenchymal Stem Cells. International Journal of Cell Biology. 2018 Dec 19; 2018:1-14. Link: International Journal of Cell Biology
  • Zeng, Z, et al. (2018) Cancer-derived exosomal miR-25-3p promotes pre-metastatic niche formation by inducing vascular permeability and angiogenesis. Nat Commun. 2018 Dec 19; 9(1):5395. PM ID: 30568162
  • Vasjari, L, et al. (2018) Ras signals principally via Erk in G1 but cooperates with PI3K/Akt for Cyclin D induction and S-phase entry. Cell Cycle. 2018 Dec 18;. PM ID: 30560710
  • Guo, D, et al. (2018) RAB27A promotes melanoma cell invasion and metastasis via regulation of pro-invasive exosomes. Int. J. Cancer. 2018 Dec 17;. PM ID: 30556600
  • Busatto, S, et al. (2018) Tangential Flow Filtration for Highly Efficient Concentration of Extracellular Vesicles from Large Volumes of Fluid. Cells. 2018 Dec 16; 7(12). PM ID: 30558352
  • Shenoy, GN, et al. (2018) Sialic Acid-Dependent Inhibition of T Cells by Exosomal Ganglioside GD3 in Ovarian Tumor Microenvironments. J. Immunol.. 2018 Dec 15; 201(12):3750-3758. PM ID: 30446565