Finaletoolkit Workflow

This Snakemake workflow automates the extraction of epigenomic features using Finaletoolkit, supporting parallel processing, SLURM, and common genomic file formats.

Key Features

• Finaletoolkit Support: Implements most Finaletoolkit CLI commands (excluding gap-bed and delfi-gc-correct).
• File Compatibility: Works with BED, BAM, and CRAM files.
• Mappability Filtering: Filters interval files based on mappability scores.
• Parallelization: Supports multi-core processing.
• SLURM Integration: Enables job submission to SLURM clusters.

Dependencies

This workflow relies on the following tools being installed and accessible by your system PATH. We recommend that you install FinaleToolkit through pip and the other packages through conda in the Bioconda channel:

• finaletoolkit: A command-line tool for epigenomic analysis.
• bedtools: A suite of utilities for working with genomic intervals.
• htslib: A library that includes bgzip, necessary to GZIP uncompressed BED files.
• samtools: A set of tools for manipulating and analyzing sequencing BAM/CRAM data

Quick Start

1. Configuration: Create a params.yaml file defining your input, output, and processing options (reference below sections).
2. Basic Execution: Run the workflow with snakemake --configfile params.yaml -c <cores> -j <jobs>.

• -c: Number of CPU cores to use.
• -j: Maximum number of concurrent jobs.

3. SLURM Execution: Submit to SLURM to run in the background with snakemake --profile slurm_profile > snakemake.log 2>&1 & (see slurm_profile/config.yaml for default settings).

Workflow Structure

• Input:
  • Genomic data files are located in the directory specified by input_dir.
  • Supplemental files (blacklist, mappability, intervals) are located in the directory specified by supplement_dir.
• Output: Processed files are written to the directory specified by output_dir.
• Configuration: params.yaml dictates workflow parameters.

YAML Parameters

• Required:

  • input_dir: Path to the input directory. Defaults to input if not specified
  • output_dir: Path to the output directory. Defaults to output if not specified.
  • file_format: "bed.gz", "bam", or "cram" indicating the format of the input files. Defaults to bed.gz if not specified.

• Optional:

  • supplement_dir: Path to supplemental files directory. Defaults to supplement if not specified.
  • mappability_file: Name of the bigWig mappability file in supplement_dir.
  • mappability_threshold: Minimum average mappability score (0.0-1.0) for interval filtering.
  • interval_file: Path to interval file in supplement_dir.
  • finaletoolkit_command: True/False: Enables a specific Finaletoolkit command, using hyphens replaced by underscores (e.g., adjust-wps becomes adjust_wps: True).
  • finaletoolkit_command_flag: value: Sets flags for a Finaletoolkit command (e.g., adjust_wps_max_length: 250). Flags that take input files, output files, or verbose flags do not exist here. mapping_quality is shortened to mapq for flags (e.g., coverage_mapping_quality becomes coverage_mapq).

Output File Naming

• Filtered Files: Files are always are given a .filtered extension before the file format when passed into the output directory (e.g., file.filtered.bed.gz).
• Command-Processed Files: Files processed by a Finaletoolkit command have the command name (with underscores) inserted before their format (e.g., file.frag_length_bins.bed.gz).
• Multiple Commands: Input files will be processed for each enabled Finaletoolkit command.

Mappability Filtering

• Uses mappability_file and mappability_threshold (float from 0-1) to filter intervals specified by interval_file.
• Interval files used in Finaletoolkit commands are pre-filtered by mappability quallity to at least the threshold if set.

Using Finaletoolkit Commands

• Finaletoolkit commands are specified in params.yaml with underscores instead of hyphens.
• Set command flags by appending _<flag_name> to the converted command name.
• Dependencies: The workflow respects command dependencies. For example, adjust-wps requires wps output, and mds needs end-motifs.

filter-file Command

• If only filter-file is set to True, the output of the workflow will be the filtered files.
• If any other Finaletoolkit commands are set, they will use the output of filter-file as their input.

Notes

• This workflow uses verbose for Finaletoolkit commands by default.
• Depreciated flags are not used in this workflow.