Single-cell ATAC-seq clustering and differential analysis by convolution-based approach

Single-cell ATAC-seq is a powerful tool to interrogate the epigenetic heterogeneity of cells. Here, we present a novel method to calculate the pairwise similarities between single cells by directly comparing their Tn5 insertion profiles instead of the binary accessibility matrix using a convolution-based approach. We demonstrate that our method retains the biological heterogeneity of single cells and is less affected by undesirable batch effects, which leads to more accurate results on downstream analyses such as dimension reduction and clustering. Based on the similarity matrix learned from epiConv, we develop an algorithm to infer differentially accessible peaks directly from heterogeneous cell population to overcome the limitations of conventional differential analysis through two-group comparisons.

[1]  Tom H. Pringle,et al.  The human genome browser at UCSC. , 2002, Genome research.

[2]  Sandy L. Klemm,et al.  Chromatin accessibility and the regulatory epigenome , 2019, Nature Reviews Genetics.

[3]  Howard Y. Chang,et al.  Lineage-specific and single cell chromatin accessibility charts human hematopoiesis and leukemia evolution , 2016, Nature Genetics.

[4]  Stein Aerts,et al.  cisTopic: cis-regulatory topic modeling on single-cell ATAC-seq data , 2019, Nature Methods.

[5]  Steven L Salzberg,et al.  Fast gapped-read alignment with Bowtie 2 , 2012, Nature Methods.

[6]  Andrew C. Adey,et al.  Cicero Predicts cis-Regulatory DNA Interactions from Single-Cell Chromatin Accessibility Data. , 2018, Molecular cell.

[7]  Howard Y. Chang,et al.  Single-cell chromatin accessibility reveals principles of regulatory variation , 2015, Nature.

[8]  Howard Y. Chang,et al.  Massively parallel single-cell chromatin landscapes of human immune cell development and intratumoral T cell exhaustion , 2019, Nature Biotechnology.

[9]  Clifford A. Meyer,et al.  Model-based Analysis of ChIP-Seq (MACS) , 2008, Genome Biology.

[10]  Alessandro Laio,et al.  Clustering by fast search and find of density peaks , 2014, Science.

[11]  Miguel A. Andrade-Navarro,et al.  Assessment of computational methods for the analysis of single-cell ATAC-seq data , 2019, Genome Biology.

[12]  Andrew C. Adey,et al.  Multiplex single-cell profiling of chromatin accessibility by combinatorial cellular indexing , 2015, Science.

[13]  William J. Greenleaf,et al.  chromVAR: Inferring transcription factor-associated accessibility from single-cell epigenomic data , 2017, Nature Methods.

[14]  Howard Y. Chang,et al.  Transposition of native chromatin for fast and sensitive epigenomic profiling of open chromatin, DNA-binding proteins and nucleosome position , 2013, Nature Methods.

[15]  Leland McInnes,et al.  UMAP: Uniform Manifold Approximation and Projection , 2018, J. Open Source Softw..

[16]  Martin J. Aryee,et al.  Droplet-based combinatorial indexing for massive-scale single-cell chromatin accessibility , 2019, Nature Biotechnology.

[17]  William S. DeWitt,et al.  A Single-Cell Atlas of In Vivo Mammalian Chromatin Accessibility , 2018, Cell.