Library Screening
VectorBuilder is your full-service platform for library construction and screening services, streamlining your research from start to finish. Our team of experts is dedicated to assisting you in experimental design, creating high-quality libraries, and performing library screens that are tailored to your specific research goals. We ensure the highest quality throughout the experimental process, from construction of NGS-validated pooled libraries to efficient deconvolution.
Highlights
One-stop shop
Optimized workflow from experimental design through library construction to screening and analysis, guided by our scientific team's unparalleled expertise in cloning and library preparation.
Customization
Tailor-made services designed to meet unique research needs, speed up timelines and improve results.
Extensive experience
Specializing in the creation of various types of high quality, high-complexity libraries with extensive coverage across a variety of genomes.
Comprehensive screening solutions
Offering both in vitro and in vivo screening to meet the broadest range of research demands.
Custom Library Construction & Screening
Premade Pooled Libraries
VectorBuilder can provide library services from start to finish or standalone offerings, providing you with exactly the service and library screen you need.
Order Now!Workflow for Library Construction
Library design
Oligo synthesis
Library cloning
NGS validation
Virus
packaging of
pooled library
packaging of
pooled library
In vitro or in
vivo screening
vivo screening
NGS
deconvolution
deconvolution
Library design
Designing an optimized library is critical to a successful screening experiment. Our technical team can help you design a library vector that is compatible with an efficient and error-less cloning process, contains proper marker or barcode sequence for versatile downstream screening experiments, and has high signal-to-noise ratio for robust results. Depending on your research needs, you can choose from our various validated delivery systems, such as lentivirus, AAV, piggyBac, non-viral regular plasmid, and adenovirus.
For CRISPR or RNAi screen, if you need assistance in designing gRNA or shRNA sequences for your list of target genes or genomic regions, VectorBuilder can help you design them using our established algorithm and computational pipeline. For 2-vector CRISPR libraries, we can also construct and package Cas9 expression vectors that are suitable for your screening strategy.
Pooled library cloning
To obtain DNA variants to be inserted in the vector backbone, we can use de novo oligo synthesis, directed evolution, or combinatorial approach. The variants are PCR amplified for a minimal number of cycles and in-parallel cloned into the desired vector backbone with high coverage. E. coli cells harboring library plasmids are propagated and harvested in exponential growth phase to make glycerol stocks. To assess the coverage and uniformity of the library, NGS analysis is performed on the plasmid pool before proceeding to virus packaging.
Virus packaging of pooled library
You may need to deliver the pooled library into cells via viral transduction, such as infecting with lentivirus or AAV. VectorBuilder has developed a range of proprietary technologies and reagents that have greatly improved virus packaging protocols for pooled libraries in terms of titer, purity, and uniformity. We can deliver the ready-to-use viral libraries for your screening experiments with a fast turnaround.
Click to view more information of virus packaging servicesIn vitro or in vivo screening
High-throughput library screening utilizes analytical methods to efficiently sift through vast libraries for a wide range of applications including gene function analysis, target identification for drug development, pathway analysis, and detection of genetic markers and phenotypes. Our technical team can help you with a diverse range of pooled screening options both in cells and in vivo tailored to meet your specific research needs, including cell viability/survival screening, drug resistance screening, pathway screening, target-based screening, toxicity screening, and custom screenings designed around your specific research objectives.
NGS deconvolution
VectorBuilder can help you identify hits by NGS for your pooled library screens. You can simply send the genomic DNA of your samples to VectorBuilder, and we will prepare the NGS libraries, perform high-throughput sequencing, analyze the data, and deliver the accurate read counts in each sample to you in just a few weeks.
Service Details
Price and turnaround Price Match
| Service Module | Brief Description | Price (USD) | Turnaround |
|---|---|---|---|
| Library design | Library vector backbone design for CRISPR, RNAi, barcode, enhancer/promoter, mutation, AAV capsid, and more pooled libraries, and gRNA or shRNA sequence design for your target genes/regions in the genome of common models. | Free | 1-4 days |
| Pooled library cloning (including oligo synthesis and NGS validation) | Massive parallel cloning of DNA variants into desired vector backbone, followed by preliminary QC by Sanger sequencing and full QC by NGS. The default deliverable is E. coli glycerol stock. | From $2,300 | 5-8 weeks |
| Virus packaging of pooled library | Please click here to view detailed info of virus packaging services. The price for packaging library is 1.5-fold of the price for packaging single vector. | ||
| Pooled screening of library samples | In vitro or in vivo screening of your libraries. Includes cell viability screening, drug resistance screening, pathway screening, reporter screens, phenotypic screening, target-based screening, toxicity screening, and other custom screenings | Please inquire | Project specific |
| NGS deconvolution of post-screening sample | Includes NGS library preparation from genomic DNA of screened cells, Illumina sequencing (>500x coverage), and data analysis. | From $320 per sample | 3-5 weeks |
How to Order
Customer-supplied library plasmid pool
If the customer-supplied premade plasmid pools are used, please send us the materials following the Materials Submission Guidelines. Please strictly follow our guidelines to set up shipment to avoid any delay or damage of materials. All customer-supplied materials undergo mandatory QC by VectorBuilder which may incur a $100 surcharge for each item. Please note that production may not be initiated until customer-supplied materials pass QC. For customer-supplied premade plasmid pools, we cannot provide any guarantees regarding the complexity or uniformity of the library.
VectorBuilder can provide library construction or library screening alone, or we can provide a combination of library construction and screening services
Order Now!Resources
Featured Citations
Genetic and pharmacological modulation of DNA mismatch repair heterogeneous tumors promotes immune surveillance
Vito Amodio, et al.
Cancer Cell, 2023, doi: 10.1016/j.ccell.2022.12.003
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Abstract: Patients affected by colorectal cancer (CRC) with DNA mismatch repair deficiency (MMRd), often respond to immune checkpoint blockade therapies, while those with mismatch repair-proficient (MMRp) tumors generally do not. Interestingly, a subset of MMRp CRCs contains variable fractions of MMRd cells, but it is unknown how their presence impacts immune surveillance. We asked whether modulation of the MMRd fraction in MMR heterogeneous tumors acts as an endogenous cancer vaccine by promoting immune surveillance. To test this hypothesis, we use isogenic MMRp (Mlh1+/+) and MMRd (Mlh1-/-) mouse CRC cells. MMRp/MMRd cells mixed at different ratios are injected in immunocompetent mice and tumor rejection is observed when at least 50% of cells are MMRd. To enrich the MMRd fraction, MMRp/MMRd tumors are treated with 6-thioguanine, which leads to tumor rejection. These results suggest that genetic and pharmacological modulation of the DNA mismatch repair machinery potentiate the immunogenicity of MMR heterogeneous tumors.
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Enhancing CRISPR deletion via pharmacological delay of DNA-PKcs
Núria Bosch-Guiteras, et al.
Genome Research, 2021, doi: 10.1101/gr.265736.120
Products used:
Abstract: CRISPR-Cas9 deletion (CRISPR-del) is the leading approach for eliminating DNA from mammalian cells and underpins a variety of genome-editing applications. Target DNA, defined by a pair of double-strand breaks (DSBs), is removed during nonhomologous end-joining (NHEJ). However, the low efficiency of CRISPR-del results in laborious experiments and false negative results. By using an endogenous reporter system, we show that repression of the DNA-dependent protein kinase catalytic subunit (DNA-PKcs)—an early step in NHEJ—yields substantial increases in DNA deletion. This is observed across diverse cell lines, gene delivery methods, commercial inhibitors, and guide RNAs, including those that otherwise display negligible activity. We further show that DNA-PKcs inhibition can be used to boost the sensitivity of pooled functional screens and detect true-positive hits that would otherwise be overlooked. Thus, delaying the kinetics of NHEJ relative to DSB formation is a simple and effective means of enhancing CRISPR-deletion.
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A Single-Cell Transcriptomics CRISPR-Activation Screen Identifies Epigenetic Regulators of the Zygotic Genome Activation Program
Celia Alda-Catalinas, et al.
Cell Systems, 2020, doi: 10.1016/j.cels.2020.06.004
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Abstract: Zygotic genome activation (ZGA) is an essential transcriptional event in embryonic development that coincides with extensive epigenetic reprogramming. Complex manipulation techniques and maternal stores of proteins preclude large-scale functional screens for ZGA regulators within early embryos. Here, we combined pooled CRISPR activation (CRISPRa) with single-cell transcriptomics to identify regulators of ZGA-like transcription in mouse embryonic stem cells, which serve as a tractable, in vitro proxy of early mouse embryos. Using multi-omics factor analysis (MOFA+) applied to ~200,000 single-cell transcriptomes comprising 230 CRISPRa perturbations, we characterized molecular signatures of ZGA and uncovered 24 factors that promote a ZGA-like response. Follow-up assays validated top screen hits, including the DNA-binding protein Dppa2, the chromatin remodeler Smarca5, and the transcription factor Patz1, and functional experiments revealed that Smarca5’s regulation of ZGA-like transcription is dependent on Dppa2. Together, our single-cell transcriptomic profiling of CRISPRa-perturbed cells provides both system-level and molecular insights into the mechanisms that orchestrate ZGA.
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