# gRNA expression matrix

`gRNA_matrix.Rd`

A gRNA-by-cell expression matrix.

    data(gRNA_matrix)

## Format

An object of class `dgTMatrix` with 50 rows and 40000 columns.

## Overview

This object is part of the example data. The data are taken from the paper "A genome-wide framework for mapping gene regulation via cellular genetic screens" by Gasperini et al., 2019. The authors used a CRISPRi-based assay to target 5,000+ putative enhancers in a population of K562 cells. The authors additionally targeted 200+ gene transcription start sites (TSSs) and designed a library of 50 non-targeting gRNAs to serve as negative controls. Genes, gRNAs, and cells are all down-sampled to reduce the size of the data.