Markov Affinity-based Graph Imputation of Cells (MAGIC)

van Dijk, David, et al. "MAGIC: A diffusion-based imputation method reveals gene-gene interactions in single-cell RNA-sequencing data." BioRxiv (2017): 111591.

http://www.biorxiv.org/content/early/2017/02/25/111591

MAGIC has been implemented in Python3, Matlab, and R.

Magic reveals the interaction between Vimentin (VIM), Cadherin-1 (CDH1), and Zinc finger E-box-binding homeobox 1 (ZEB1, encoded by colors).

Python3

Installation and dependencies for the Python version

1. The Python3 version of MAGIC can be installed using:

    $> git clone git://github.com/KrishnaswamyLab/magic.git
    $> cd magic/python
    $> sudo -H pip3 install .
   

2. MAGIC depends on a number of python3 packages available on pypi and these dependencies are listed in setup.py All the dependencies will be automatically installed using the above commands

3. After pulling updates to MAGIC from github, the package must be uninstalled and reinstalled:

    $> sudo -H pip3 uninstall magic
    $> sudo -H pip3 install .
   

Usage

Interactive command line

We have included two tutorial notebooks on MAGIC usage and results visualization for single cell RNA-seq data.

EMT data notebook: http://nbviewer.jupyter.org/github/KrishnaswamyLab/magic/blob/develop/python/tutorial_notebooks/Magic_single_cell_RNAseq_EMT_data.ipynb

Bone Marrow data notebook: http://nbviewer.jupyter.org/github/KrishnaswamyLab/magic/blob/develop/python/tutorial_notebooks/Magic_single_cell_RNAseq_bone_marrow_data.ipynb

GUI

A python GUI is now available for MAGIC. After following the installation steps listed below, the GUI can be invoked using

    $> magic_gui.py

Command line script

MAGIC can be run using the command line script MAGIC.py with the following parameters:

	$> MAGIC.py -h
	usage: MAGIC.py [-h] -d D -o O [-g G] [--gene-name-file GN]
            [--use-ensemble-ids] [--cell-axis CA] [--skip-rows SKIP_ROWS]
            [--skip-columns SKIP_COLUMNS] [-n] [-l L]
            [--mols-per-cell-min MOLS_PER_CELL_MIN]
            [--mols-per-cell-max MOLS_PER_CELL_MAX] [-p P]
            [--pca-non-random] [-t T] [-k K] [-ka KA] [-e E] [-r R]
            [--plot] [--t-max TM] [--n-genes NG]
            {csv,10x,10x_HDF5,mtx}

	run MAGIC

	positional arguments:
	  {csv,10x,10x_HDF5,mtx}
	                        what is the file type of your original data?

	optional arguments:
	  -h, --help            show this help message and exit

	data loading parameters:
	  -d D, --data-file D   File path of input data file.
	  -o O, --output-file O
	                        File path of where to save the MAGIC imputed data (in
	                        csv format).
	  -g G, --genome G      Genome must be specified when loading 10x_HDF5 data.
	  --gene-name-file GN   Gene name file must be specified when loading mtx
	                        data.
	  --use-ensemble-ids    Use ensemble IDs instead of gene names.
	  --cell-axis CA        When loading a csv, specify whether cells are on rows
	                        or columns (Default = 'rows').
	  --skip-rows SKIP_ROWS
	                        When loading a csv, number of rows to skip after the
	                        header row (Default = 0).
	  --skip-columns SKIP_COLUMNS
	                        When loading a csv, number of columns to skip after
	                        the header columns (Default = 0).

	normalization/filtering parameters:
	  -n, --no-normalize    Do not perform library size normalization on the data
	  -l L, --log-transform L
	                        Log-transform data with the specified pseudocount.
	  --mols-per-cell-min MOLS_PER_CELL_MIN
	                        Minimum molecules/cell to use in filtering.
	  --mols-per-cell-max MOLS_PER_CELL_MAX
	                        Maximum molecules/cell to use in filtering.

	MAGIC parameters:
	  -p P, --pca-components P
	                        Number of pca components to use when running MAGIC
	                        (Default = 20).
	  --pca-non-random      Do not used randomized solver in PCA computation.
	  -t T                  t parameter for running MAGIC. Default = None, in this
	                        case, the optimal t will be calculated .
	  -k K                  Number of nearest neighbors to use when running MAGIC
	                        (Default = 30).
	  -ka KA                knn-autotune parameter for running MAGIC (Default =
	                        10).
	  -e E, --epsilon E     Epsilon parameter for running MAGIC (Default = 1).
	  -r R, --rescale R     Percentile to rescale data to after running MAGIC
	                        (Default = 99).
	  --plot                Plot R2 plot generated in optimal t calculation
	                        (Default=False).
	  --t-max TM            Maximum t value used in optimal t calculation
	                        (Default=12).
	  --n-genes NG          Number of genes to use in optimal t calculation, a
	                        smaller number of genes speeds up the calculation
	                        (Default=500).

Matlab

Instructions for the Matlab version

1. run_magic.m -- MAGIC imputation function
2. test_magic.m -- Shows how to run MAGIC. Also included is a function for loading 10x format data (load_10x.m)

R

Installation and dependencies for the R version

1. The R version of MAGIC can be installed using:

    $> library("devtools")
    $> install_github("KrishnaswamyLab/magic/R")
   

2. MAGIC depends on a number of R packages and these dependencies are listed in DESCRIPTION All the dependencies will be automatically installed using the above commands

Usage

After installing the package, MAGIC can be run by loading the library and calling run_magic():

$> library(Rmagic)
$> MAGIC_data <- run_magic(data, t=6, rescale_percent=0.99)

For a working example, see R/tests/test_magic.R. Please unzip the data provided in the data folder.