Abstract
Prader-Willi syndrome (PWS) is characterized by neonatal hypotonia, developmental delay, and hyperphagia/obesity. This disorder is caused by the absence of paternally-expressed gene products from chromosome 15q11-q13. We previously demonstrated that knocking out ZNF274, a KRAB-domain zinc finger protein capable of recruiting epigenetic machinery to deposit the H3K9me3 repressive histone modification, can activate expression from the normally silent maternal allele of SNORD116 in neurons derived from PWS iPSCs. However, ZNF274 has many other targets in the genome in addition to SNORD116. Depleting ZNF274 will surely affect the expression of other important genes and disrupt other pathways. Here we used CRISPR/Cas9 to delete ZNF274 binding sites at the SNORD116 locus to determine whether activation of the maternal copy of SNORD116 could be achieved without altering ZNF274 protein levels. We obtained similar activation of gene expression from the normally silenced maternal allele in neurons derived from PWS iPSCs, compared to ZNF274 knockout, demonstrating that ZNF274 is directly involved in the repression of SNORD116. These results suggest that interfering with ZNF274 binding at the maternal SNORD116 locus is a potential therapeutic strategy for PWS.
Competing Interest Statement
The authors have declared no competing interest.
Abbreviations
- 116HGG2
- SNORD116 host gene Group2 transcript
- 3’UTR
- 3’ Untranslated Transcribed Region
- AS
- Angelman syndrome
- ChIP
- Chromatin ImmunoPrecipitation
- CRISPR
- Clustered Regularly Interspaced Short Palindromic Repeats
- Cas9
- CRISPR associated protein 9
- CTRL
- iPSCs from control individuals
- G9a
- histone methyltransferase
- H3K9me2
- histone H3 lysine 9 dimethylation
- H3K9me3
- histone H3 lysine 9 trimethylation
- HG
- host gene
- iPSCs
- induced pluripotent stem cells
- lncRNA
- long non-coding RNA
- NPCs
- neural progenitor cells
- PWS
- Prader-Willi syndrome
- PWS-IC
- PWS-Imprinting Center
- SETDB1
- SET domain bifurcated 1
- SNOG1
- SNORD116 Group 1
- SNOG2
- SNORD116 Group 2
- SNOG3
- SNORD116 Group 3
- SNORD115
- box C/D class small nucleolar RNAs
- SNORD116
- box C/D class small nucleolar RNAs
- SNRPN
- small nuclear ribonucleoprotein polypeptide N
- UBE3A
- Ubiquitin Protein Ligase E3A
- UBE3A-ATS
- antisense overlapping UBE3A transcript
- ZNF274
- zinc-finger protein ZNF274
- ZNF274 BS
- ZNF274 binding sites
- LD KO1 & 3
- ZNF274 knockout from PWS large deletion (LD) iPSCs