In eukaryotes, DNA replication and gene transcription require the unwinding of the high-level structure of the genome. But only a few areas need to be opened, and which areas of the genome are accessible, revealing a lot of information about the state of the cell. These areas opened are termed as open chromatin. Once chromatin is turned on, some regulatory proteins (such as transcription factors and cofactors) are allowed to bind to it. This property of chromatin is called chromatin accessibility. Finding open chromatin regions can help us gain insight into the mechanisms of gene regulation.

Creative BioMart offers ATAC-Seq (assay for transposase accessible chromatin with high-throughput sequencing) service, a rapid and sensitive technique for studying chromatin accessibility. Moreover, ATAC-Seq can be a good alternative to ChIP-Seq (chromatin immunoprecipitation sequencing) if it is not known whether epigenetics plays a role in the response of cell systems, if it is not clear which histone modification is the most significant to study using ChIP-Seq or when the number of cells is limited.

What Is ATAC-Seq?

ATAC-Seq is a high-throughput sequencing technology that utilizes transposase to study chromatin accessibility. The mutant Tn5 transposases preloaded with DNA adapters are added to the genome, which is fragmented in the open chromatin region and the adaptor is added simultaneously. Subsequently, using the tags of known sequences for PCR amplification and in-depth sequencing, we will know which regions open chromatin are. ATAC-Seq captures open chromatin sites using a simple two-step protocol with 500-50,000 cells and reveals the interplay between genomic locations of open chromatin, DNA-binding proteins, individual nucleosomes and chromatin compaction at single nucleotide resolution. The repeatability of ATAC-Seq is stronger than that of MNase-Seq and DNase-Seq, and this approach requires only a small amount of cells/tissue, in addition, the signals coming out are more beautiful. The assay provides a genome-wide profile of the open and accessible regions of chromatin, indicating the region of active regulatory. At present, this technique has been the preferred technical method for studying chromatin accessibility and is becoming part of standard epigenetic analysis.

Figure 1. Schematic illustration of the principle behind ATAC-Seq

Applications of ATAC-Seq

1. Nucleosome mapping which identifies subtle changes in nucleosome position between experimental conditions, and correlation with sequence context
2. Transcription factor (TF) occupancy analysis in specific cell types
3. Identifying novel enhancers during development
4. In addition to normal development, ATAC-Seq can be utilized to explore various pathological conditions

Our Advantages

1. Tolerance of multiple sample types: we accept the following sample types for this service, including but not limited in human, animal, and plant tissues (frozen tissues are also allowed), primary cells, fluorescence-activated cell sorting (FACS) sorted cells and most rare cell populations.
2. One-stop service: customers only need to provide samples, and we will complete full ATAC-Seq experiment from cell preparation, transposase reaction, library amplification, on-machine sequencing to bioinformatics analysis. We also offer free project consultation.
3. Reliable data quality: we guarantee that more than 80% of bases with a ≥Q30 quality score, exceeding Illumina’s official guarantee of ≥ 75%.
4. Professional data analysis: we will provide data analysis upon request. The quality of the ATAC-Seq data set can be assessed using multiple methods, including the two parameters considered to be the most important, FRiP Score and Peak Number.

Workflow of ATAC-Seq at Creative BioMart

Creative BioMart stringently controls each step in the ATAC-Seq service workflow to ensure access to unsurpassed data quality. If you have a need, our optimized protocol can be used for tissues such as blood (Fast-ATAC), neurons, biological specimens and single cells (single-cell ATAC-Seq).

Figure 2. Workflow of ATAC-Seq service at Creative BioMart

Our excellent staffs with abundant project experience and professional know-how, will work together with you closely and report the project progress in time. Creative BioMart has confidence in accelerating your epigenetic analysis project and delivering the final products with short turnaround time and high-quality. If you have additional requirements or questions about our ATAC-Seq service, please feel free to contact us.

References
1. Buenrostro J D.; et al. Transposition of native chromatin for fast and sensitive epigenomic profiling of open chromatin, DNA-binding proteins and nucleosome position. Nature Methods. 2013, 10(12): 1213-1218.
2. Corces M R.; et al. An improved ATAC-seq protocol reduces background and enables interrogation of frozen tissues. Nature Methods. 2017, 14(10): 959-962.