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Toronto KnockOut (TKO) CRISPR Library - Version 3
(Pooled Libraries #90294, #125517)

  • Purpose

    Human CRISPR lentiviral library that has 70,948 guides (4 guides/gene) targeting 18,053 protein-coding genes.

  • Vector Backbone

    Available in either a 1 vector (lentiCRISPRv2 backbone) or 2 vector (pLCKO2 backbone) system.


Item Catalog # Description Quantity Price (USD)
Pooled Library 90294 gRNA pooled library in lentiCRISPRv2
Original TKOv3
1 $540 Add to Cart
Pooled Library 125517 gRNA pooled library in pLCKO2 1 $540 Add to Cart
Available to Academic and Nonprofits Only

Library Details

  • Species
  • Genes targeted
  • gRNAs
  • Controls
    142 guides targeting LacZ, EGFP, and luciferase
  • Lentiviral Generation

Library Shipping

This library will be delivered as a pooled DNA library in a microcentrifuge tube on blue ice. The tube's contents will not necessarily be frozen. For best results, minimize freeze-thaws.

  • Volume
    ∼20 µL
  • Concentration
    50 ng/µL

Resource Information

Depositor Comments

The Toronto KnockOut Library v3 (TKOv3) contains 70,948 gRNAs targeting 18,053 protein coding genes (4 gRNAs/gene) with 142 control gRNAs targeting EGFP, LacZ, and luciferase (71,090 total).

The gRNAs in this library are optimized for editing efficiency using empirical data described in the associated article. As a result, the number of gRNAs per gene is decreased to 4 based on the finding that there are diminishing benefits to more gRNAs per gene beyond four. The optimized library size of TKOv3 offers the benefit of improved accuracy, efficiency and scalability for CRISPR screens.

This library is available in two formats: 1) as a one-component library that contains Cas9, alleviating the need to include a separate Cas9 and 2) as a two-component without Cas9, that can be utilized in cells that stably express Cas9.

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How to cite this pooled library ( Back to top )

These pooled libraries were created by your colleagues. Please acknowledge the Principal Investigator, cite the article in which the pooled libraries were described, and include Addgene in the Materials and Methods of your future publications.

  • Example for your Materials & Methods section:

    Toronto human knockout pooled library (TKOv3) was a gift from Jason Moffat (Addgene #)
  • For your References section:

    For #90294: Evaluation and Design of Genome-Wide CRISPR/SpCas9 Knockout Screens. Hart T, Tong AHY, Chan K, Van Leeuwen J, Seetharaman A, Aregger M, Chandrashekhar M, Hustedt N, Seth S, Noonan A, Habsid A, Sizova O, Nedyalkova L, Climie R, Tworzyanski L, Lawson K, Sartori MA, Alibeh S, Tieu D, Masud S, Mero P, Weiss A, Brown KR, Usaj M, Billmann M, Rahman M, Constanzo M, Myers CL, Andrews BJ, Boone C, Durocher D, Moffat J. G3 (Bethesda). Aug 7;7(8):2719-2727. doi: 10.1534/g3.117.041277. PubMed 28655737
    For #125517: Essential Gene Profiles for Human Pluripotent Stem Cells Identify Uncharacterized Genes and Substrate Dependencies. Mair B, Tomic J, Masud SN, Tonge P, Weiss A, Usaj M, Tong AHY, Kwan JJ, Brown KR, Titus E, Atkins M, Chan KSK, Munsie L, Habsid A, Han H, Kennedy M, Cohen B, Keller G, Moffat J. Cell Rep. 2019 Apr 9;27(2):599-615.e12. doi: 10.1016/j.celrep.2019.02.041. PubMed 30970261