The Hsp40 co-chaperone DNAJC7 regulates polyglutamine aggregation and exhibits context-dependent effects on polyglycine aggregation

Protein-encoding nucleotide repeat expansion diseases, including polyglutamine (polyQ) and polyglycine (polyG) diseases, are characterized by the accumulation of aggregation-prone proteins. In the polyQ diseases, including Huntington’s disease and several spinocerebellar ataxias, substantial prior evidence supports a pathogenic role for mutant polyQ-expanded protein misfolding and aggregation, with molecular chaperones showing promise in suppressing disease phenotypes in cellular and animal models. The goal of this study is to establish a scalable cell-based model to systematically evaluate genetic modifiers of protein aggregation in both polyQ and polyG diseases. We developed FRET-based reporter systems that model polyQ and polyG aggregation in human cells and used them to perform high-throughput CRISPR interference screens targeting all known molecular chaperones. In the polyQ model, the screen identified multiple Hsp70 chaperones (HSPA8, HSPA4) and Hsp40 co-chaperones (DNAJB6, DNAJB1..., HEK293T cells containing CRISPRi machinery1 were transduced with lentiviral constructs expressing doxycycline-inducible, nuclear-localized polyQ or polyG proteins that are aggregation-prone. The proteins were also fluorescently tagged (mScarlet and mNeonGreen). This fluorescence pair allows FRET-based readout of protein aggregation. We subsequently generated a monoclonal cell line for the FRET-paired polyQ or polyG inducible protein expression, and designated it as NLS-FRET-Q79 or NLS-FRET-G100, respectively. 
The cell lines were transduced with a sgRNA library consisting of 2071 sgRNAs targeting nearly all known molecular chaperones (356 genes) along with non-targeting controls, as previously described2. On Day 2, with ∼30 % of the cells showing BFP positivity, the cells were passaged and replated with 2 μg/ml puromycin (Gibco, A1113803). This was repeated on day 5. On day 7, with > 70 % of cells showing BFP positivity, the cells were passaged and 20 million cells were pla..., # Data from: The Hsp40 co-chaperone DNAJC7 regulates polyglutamine aggregation and exhibits context-dependent effects on polyglycine aggregation

Dataset DOI: [10.5061/dryad.0gb5mkmdh](10.5061/dryad.0gb5mkmdh)

## Description of the data and file structure

The data included in this submission are the raw FASTQ files generated from sequencing of CRISPR sgRNA protospacers from HEK293T cells toward identifying molecular chaperone modifiers of polyglutamine (polyQ) or polyglycine (polyG) protein aggregation. Also included are the two tables containing information on the sgRNA protospacer sequences and their target genes; these tables were used to align the protospacer sequences from each FASTQ file to the targeted gene. The polyQ screen was performed twice, and the polyG screen was performed once. 

### Files and variables

#### File: human_chap_crispri.g2s.txt

**Description:** A table that provides the targeted gene for each sgRNA identifier

##### Variables: N/A

#### File: human_chap_c..., ,