Sequencing Library
Sequencing Library - Related Videos
12:01
3' End Sequencing Library Preparation with A-seq2
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Cited by 6 •
2017
This protocol describes a method for mapping pre-mRNA 3' end processing sites.
12:05
RIBO-seq in Bacteria: a Sample Collection and Library Preparation Protocol for NGS Sequencing
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Cited by 4 •
2021
Here we describe the stages of sample collection and preparation for RIBO-seq in bacteria. Sequencing of the libraries prepared according to these guidelines results in sufficient data for comprehensive bioinformatic analysis. The protocol we present is simple, uses standard laboratory equipment and takes seven days from lysis to obtaining libraries.
10:05
Generation of Native Chromatin Immunoprecipitation Sequencing Libraries for Nucleosome Density Analysis
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Cited by 9 •
2017
We present a modified native chromatin immunoprecipitation sequencing (ChIP-seq) methodology for the generation of sequence datasets suitable for a nucleosome density ChIP-seq analytical framework integrating micrococcal nuclease (MNase) accessibility with histone modification measurements.
11:36
A Protocol for Functional Assessment of Whole-Protein Saturation Mutagenesis Libraries Utilizing High-Throughput Sequencing
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Cited by 5 •
2016
We present a protocol for the functional assessment of comprehensive single-site saturation mutagenesis libraries of proteins utilizing high-throughput sequencing. Importantly, this approach uses orthogonal primer pairs to multiplex library construction and sequencing. Representative results using TEM-1 β-lactamase selected at a clinically relevant dosage of ampicillin are provided.
08:37
Preparation of Small RNA Libraries for Sequencing from Early Mouse Embryos
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Cited by 1 •
2020
We describe a technique for profiling microRNAs in early mouse embryos. This protocol overcomes the challenge of low cell input and small RNA enrichment. This assay can be used to analyze changes in miRNA expression over time in different cell lineages of the early mouse embryo.
FAQs
Adapters create the molecular features needed to connect prepared DNA or DNA-derived molecules with the sequencing process. Index sequences identify the sample associated with each molecule, allowing material from multiple samples to be analyzed in parallel. This design helps organize sequence results by source after high-throughput sequencing and supports efficient comparison of samples in genetic studies.
Fragmentation converts genomic DNA or complementary DNA into molecules suitable for library construction, while end repair prepares their molecule ends for adapter attachment. Together, these steps transform the starting genetic material into a collection that can proceed through sequencing. Their success affects which DNA-derived molecules become templates and therefore contributes to the resulting coverage and data quality.
Amplification increases the amount of selected library material, whereas enrichment focuses the prepared collection before sequencing. These steps are optional rather than universal, so their use depends on the library design and research goal. When applied appropriately, they help provide sufficient or more targeted template material for analyzing selected genetic regions or other features.
The starting material determines the biological information represented in the collection. Genomic DNA supports analyses of genome-wide or selected genomic regions, including genome, exome, and targeted sequencing. Complementary DNA, produced from RNA, supports transcriptome-oriented analysis and can reveal gene expression patterns. Thus, library preparation connects the same sequencing framework to different genetic questions.
Construction begins with genomic DNA or complementary DNA, followed by fragmentation and end repair. Prepared molecules are joined to sequencing adapters, and sample-specific indexes may be incorporated. Depending on the experiment, selected molecules are then amplified or enriched before sequencing. The completed preparation is used as the template for determining nucleotide sequences and analyzing genomic features.
Library quality directly influences data accuracy and coverage, so preparation must preserve a useful representation of the starting genetic material and produce molecules compatible with sequencing. Problems during fragmentation, end repair, adapter joining, indexing, amplification, or enrichment can affect which templates are represented. Evaluating the prepared library is therefore important before interpreting variants, expression patterns, or other results.
The choice follows the biological scope of the question. Genome libraries support broad analysis across genetic material, exome libraries focus on exome-associated regions, and targeted libraries concentrate on selected regions. Transcriptome libraries are suited to studying gene expression patterns from complementary DNA. These options let genetics researchers balance broad feature discovery with focused investigation of particular sequences or processes.